diff --git a/libs/WindowManager/Shell/src/com/android/wm/shell/bubbles/ManageEducationView.kt b/libs/WindowManager/Shell/src/com/android/wm/shell/bubbles/ManageEducationView.kt
index e95e8e5cdaea1..1b41f793311d0 100644
--- a/libs/WindowManager/Shell/src/com/android/wm/shell/bubbles/ManageEducationView.kt
+++ b/libs/WindowManager/Shell/src/com/android/wm/shell/bubbles/ManageEducationView.kt
@@ -41,9 +41,9 @@ class ManageEducationView constructor(context: Context, positioner: BubblePositi
     private val ANIMATE_DURATION: Long = 200
 
     private val positioner: BubblePositioner = positioner
-    private val manageView by lazy { findViewById<ViewGroup>(R.id.manage_education_view) }
-    private val manageButton by lazy { findViewById<Button>(R.id.manage_button) }
-    private val gotItButton by lazy { findViewById<Button>(R.id.got_it) }
+    private val manageView by lazy { requireViewById<ViewGroup>(R.id.manage_education_view) }
+    private val manageButton by lazy { requireViewById<Button>(R.id.manage_button) }
+    private val gotItButton by lazy { requireViewById<Button>(R.id.got_it) }
 
     private var isHiding = false
     private var realManageButtonRect = Rect()
@@ -122,7 +122,7 @@ class ManageEducationView constructor(context: Context, positioner: BubblePositi
             manageButton
                 .setOnClickListener {
                     hide()
-                    expandedView.findViewById<View>(R.id.manage_button).performClick()
+                    expandedView.requireViewById<View>(R.id.manage_button).performClick()
                 }
             gotItButton.setOnClickListener { hide() }
             setOnClickListener { hide() }
diff --git a/libs/WindowManager/Shell/src/com/android/wm/shell/bubbles/StackEducationView.kt b/libs/WindowManager/Shell/src/com/android/wm/shell/bubbles/StackEducationView.kt
index d0598cd285828..5e3a077a3716e 100644
--- a/libs/WindowManager/Shell/src/com/android/wm/shell/bubbles/StackEducationView.kt
+++ b/libs/WindowManager/Shell/src/com/android/wm/shell/bubbles/StackEducationView.kt
@@ -48,9 +48,9 @@ class StackEducationView constructor(
     private val positioner: BubblePositioner = positioner
     private val controller: BubbleController = controller
 
-    private val view by lazy { findViewById<View>(R.id.stack_education_layout) }
-    private val titleTextView by lazy { findViewById<TextView>(R.id.stack_education_title) }
-    private val descTextView by lazy { findViewById<TextView>(R.id.stack_education_description) }
+    private val view by lazy { requireViewById<View>(R.id.stack_education_layout) }
+    private val titleTextView by lazy { requireViewById<TextView>(R.id.stack_education_title) }
+    private val descTextView by lazy { requireViewById<TextView>(R.id.stack_education_description) }
 
     var isHiding = false
         private set
diff --git a/libs/WindowManager/Shell/src/com/android/wm/shell/desktopmode/DesktopTasksController.kt b/libs/WindowManager/Shell/src/com/android/wm/shell/desktopmode/DesktopTasksController.kt
index a4c086b1c604a..d8ce427dc3ee8 100644
--- a/libs/WindowManager/Shell/src/com/android/wm/shell/desktopmode/DesktopTasksController.kt
+++ b/libs/WindowManager/Shell/src/com/android/wm/shell/desktopmode/DesktopTasksController.kt
@@ -313,7 +313,7 @@ class DesktopTasksController(
             task.taskId
         )
         val wct = WindowContainerTransaction()
-        wct.setBounds(task.token, null)
+        wct.setBounds(task.token, Rect())
 
         if (Transitions.ENABLE_SHELL_TRANSITIONS) {
             enterDesktopTaskTransitionHandler.startCancelMoveToDesktopMode(wct,
@@ -550,6 +550,7 @@ class DesktopTasksController(
         )
         // Check if we should skip handling this transition
         var reason = ""
+        val triggerTask = request.triggerTask
         val shouldHandleRequest =
             when {
                 // Only handle open or to front transitions
@@ -558,19 +559,19 @@ class DesktopTasksController(
                     false
                 }
                 // Only handle when it is a task transition
-                request.triggerTask == null -> {
+                triggerTask == null -> {
                     reason = "triggerTask is null"
                     false
                 }
                 // Only handle standard type tasks
-                request.triggerTask.activityType != ACTIVITY_TYPE_STANDARD -> {
-                    reason = "activityType not handled (${request.triggerTask.activityType})"
+                triggerTask.activityType != ACTIVITY_TYPE_STANDARD -> {
+                    reason = "activityType not handled (${triggerTask.activityType})"
                     false
                 }
                 // Only handle fullscreen or freeform tasks
-                request.triggerTask.windowingMode != WINDOWING_MODE_FULLSCREEN &&
-                        request.triggerTask.windowingMode != WINDOWING_MODE_FREEFORM -> {
-                    reason = "windowingMode not handled (${request.triggerTask.windowingMode})"
+                triggerTask.windowingMode != WINDOWING_MODE_FULLSCREEN &&
+                        triggerTask.windowingMode != WINDOWING_MODE_FREEFORM -> {
+                    reason = "windowingMode not handled (${triggerTask.windowingMode})"
                     false
                 }
                 // Otherwise process it
@@ -586,17 +587,17 @@ class DesktopTasksController(
             return null
         }
 
-        val task: RunningTaskInfo = request.triggerTask
-
-        val result = when {
-            // If display has tasks stashed, handle as stashed launch
-            desktopModeTaskRepository.isStashed(task.displayId) -> handleStashedTaskLaunch(task)
-            // Check if fullscreen task should be updated
-            task.windowingMode == WINDOWING_MODE_FULLSCREEN -> handleFullscreenTaskLaunch(task)
-            // Check if freeform task should be updated
-            task.windowingMode == WINDOWING_MODE_FREEFORM -> handleFreeformTaskLaunch(task)
-            else -> {
-                null
+        val result = triggerTask?.let { task ->
+            when {
+                // If display has tasks stashed, handle as stashed launch
+                desktopModeTaskRepository.isStashed(task.displayId) -> handleStashedTaskLaunch(task)
+                // Check if fullscreen task should be updated
+                task.windowingMode == WINDOWING_MODE_FULLSCREEN -> handleFullscreenTaskLaunch(task)
+                // Check if freeform task should be updated
+                task.windowingMode == WINDOWING_MODE_FREEFORM -> handleFreeformTaskLaunch(task)
+                else -> {
+                    null
+                }
             }
         }
         KtProtoLog.v(
@@ -703,7 +704,7 @@ class DesktopTasksController(
             WINDOWING_MODE_FULLSCREEN
         }
         wct.setWindowingMode(taskInfo.token, targetWindowingMode)
-        wct.setBounds(taskInfo.token, null)
+        wct.setBounds(taskInfo.token, Rect())
         if (isDesktopDensityOverrideSet()) {
             wct.setDensityDpi(taskInfo.token, getDefaultDensityDpi())
         }
diff --git a/libs/WindowManager/Shell/src/com/android/wm/shell/desktopmode/ToggleResizeDesktopTaskTransitionHandler.kt b/libs/WindowManager/Shell/src/com/android/wm/shell/desktopmode/ToggleResizeDesktopTaskTransitionHandler.kt
index b9cb5c75aaf0a..9debb25ff2962 100644
--- a/libs/WindowManager/Shell/src/com/android/wm/shell/desktopmode/ToggleResizeDesktopTaskTransitionHandler.kt
+++ b/libs/WindowManager/Shell/src/com/android/wm/shell/desktopmode/ToggleResizeDesktopTaskTransitionHandler.kt
@@ -69,7 +69,7 @@ class ToggleResizeDesktopTaskTransitionHandler(
     ): Boolean {
         val change = findRelevantChange(info)
         val leash = change.leash
-        val taskId = change.taskInfo.taskId
+        val taskId = checkNotNull(change.taskInfo).taskId
         val startBounds = change.startAbsBounds
         val endBounds = change.endAbsBounds
         val windowDecor =
diff --git a/libs/WindowManager/Shell/src/com/android/wm/shell/windowdecor/viewholder/DesktopModeAppControlsWindowDecorationViewHolder.kt b/libs/WindowManager/Shell/src/com/android/wm/shell/windowdecor/viewholder/DesktopModeAppControlsWindowDecorationViewHolder.kt
index 672e57aab5adc..a9eb8829bd2c8 100644
--- a/libs/WindowManager/Shell/src/com/android/wm/shell/windowdecor/viewholder/DesktopModeAppControlsWindowDecorationViewHolder.kt
+++ b/libs/WindowManager/Shell/src/com/android/wm/shell/windowdecor/viewholder/DesktopModeAppControlsWindowDecorationViewHolder.kt
@@ -23,14 +23,14 @@ internal class DesktopModeAppControlsWindowDecorationViewHolder(
         appIcon: Drawable
 ) : DesktopModeWindowDecorationViewHolder(rootView) {
 
-    private val captionView: View = rootView.findViewById(R.id.desktop_mode_caption)
-    private val captionHandle: View = rootView.findViewById(R.id.caption_handle)
-    private val openMenuButton: View = rootView.findViewById(R.id.open_menu_button)
-    private val closeWindowButton: ImageButton = rootView.findViewById(R.id.close_window)
-    private val expandMenuButton: ImageButton = rootView.findViewById(R.id.expand_menu_button)
-    private val maximizeWindowButton: ImageButton = rootView.findViewById(R.id.maximize_window)
-    private val appNameTextView: TextView = rootView.findViewById(R.id.application_name)
-    private val appIconImageView: ImageView = rootView.findViewById(R.id.application_icon)
+    private val captionView: View = rootView.requireViewById(R.id.desktop_mode_caption)
+    private val captionHandle: View = rootView.requireViewById(R.id.caption_handle)
+    private val openMenuButton: View = rootView.requireViewById(R.id.open_menu_button)
+    private val closeWindowButton: ImageButton = rootView.requireViewById(R.id.close_window)
+    private val expandMenuButton: ImageButton = rootView.requireViewById(R.id.expand_menu_button)
+    private val maximizeWindowButton: ImageButton = rootView.requireViewById(R.id.maximize_window)
+    private val appNameTextView: TextView = rootView.requireViewById(R.id.application_name)
+    private val appIconImageView: ImageView = rootView.requireViewById(R.id.application_icon)
 
     init {
         captionView.setOnTouchListener(onCaptionTouchListener)
@@ -47,7 +47,9 @@ internal class DesktopModeAppControlsWindowDecorationViewHolder(
     override fun bindData(taskInfo: RunningTaskInfo) {
 
         val captionDrawable = captionView.background as GradientDrawable
-        captionDrawable.setColor(taskInfo.taskDescription.statusBarColor)
+        taskInfo.taskDescription?.statusBarColor?.let {
+            captionDrawable.setColor(it)
+        }
 
         closeWindowButton.imageTintList = ColorStateList.valueOf(
                 getCaptionCloseButtonColor(taskInfo))
diff --git a/libs/WindowManager/Shell/src/com/android/wm/shell/windowdecor/viewholder/DesktopModeFocusedWindowDecorationViewHolder.kt b/libs/WindowManager/Shell/src/com/android/wm/shell/windowdecor/viewholder/DesktopModeFocusedWindowDecorationViewHolder.kt
index 47a12a0cb71c6..9374ac95e83dd 100644
--- a/libs/WindowManager/Shell/src/com/android/wm/shell/windowdecor/viewholder/DesktopModeFocusedWindowDecorationViewHolder.kt
+++ b/libs/WindowManager/Shell/src/com/android/wm/shell/windowdecor/viewholder/DesktopModeFocusedWindowDecorationViewHolder.kt
@@ -17,8 +17,8 @@ internal class DesktopModeFocusedWindowDecorationViewHolder(
         onCaptionButtonClickListener: View.OnClickListener
 ) : DesktopModeWindowDecorationViewHolder(rootView) {
 
-    private val captionView: View = rootView.findViewById(R.id.desktop_mode_caption)
-    private val captionHandle: ImageButton = rootView.findViewById(R.id.caption_handle)
+    private val captionView: View = rootView.requireViewById(R.id.desktop_mode_caption)
+    private val captionHandle: ImageButton = rootView.requireViewById(R.id.caption_handle)
 
     init {
         captionView.setOnTouchListener(onCaptionTouchListener)
@@ -27,9 +27,10 @@ internal class DesktopModeFocusedWindowDecorationViewHolder(
     }
 
     override fun bindData(taskInfo: RunningTaskInfo) {
-        val captionColor = taskInfo.taskDescription.statusBarColor
-        val captionDrawable = captionView.background as GradientDrawable
-        captionDrawable.setColor(captionColor)
+        taskInfo.taskDescription?.statusBarColor?.let { captionColor ->
+            val captionDrawable = captionView.background as GradientDrawable
+            captionDrawable.setColor(captionColor)
+        }
 
         captionHandle.imageTintList = ColorStateList.valueOf(getCaptionHandleBarColor(taskInfo))
     }
diff --git a/libs/WindowManager/Shell/src/com/android/wm/shell/windowdecor/viewholder/DesktopModeWindowDecorationViewHolder.kt b/libs/WindowManager/Shell/src/com/android/wm/shell/windowdecor/viewholder/DesktopModeWindowDecorationViewHolder.kt
index d293cf73a0f78..49e8d15dcc02d 100644
--- a/libs/WindowManager/Shell/src/com/android/wm/shell/windowdecor/viewholder/DesktopModeWindowDecorationViewHolder.kt
+++ b/libs/WindowManager/Shell/src/com/android/wm/shell/windowdecor/viewholder/DesktopModeWindowDecorationViewHolder.kt
@@ -25,11 +25,14 @@ internal abstract class DesktopModeWindowDecorationViewHolder(rootView: View) {
    * with the caption background color.
    */
   protected fun shouldUseLightCaptionColors(taskInfo: RunningTaskInfo): Boolean {
-    return if (Color.alpha(taskInfo.taskDescription.statusBarColor) != 0 &&
-        taskInfo.windowingMode == WINDOWING_MODE_FREEFORM) {
-      Color.valueOf(taskInfo.taskDescription.statusBarColor).luminance() < 0.5
-    } else {
-      taskInfo.taskDescription.statusBarAppearance and APPEARANCE_LIGHT_STATUS_BARS == 0
-    }
+    return taskInfo.taskDescription
+        ?.let { taskDescription ->
+          if (Color.alpha(taskDescription.statusBarColor) != 0 &&
+              taskInfo.windowingMode == WINDOWING_MODE_FREEFORM) {
+            Color.valueOf(taskDescription.statusBarColor).luminance() < 0.5
+          } else {
+            taskDescription.statusBarAppearance and APPEARANCE_LIGHT_STATUS_BARS == 0
+          }
+        } ?: false
   }
 }
diff --git a/packages/SettingsLib/src/com/android/settingslib/graph/ThemedBatteryDrawable.kt b/packages/SettingsLib/src/com/android/settingslib/graph/ThemedBatteryDrawable.kt
index a03acc3a078ce..73f6db6d464b6 100644
--- a/packages/SettingsLib/src/com/android/settingslib/graph/ThemedBatteryDrawable.kt
+++ b/packages/SettingsLib/src/com/android/settingslib/graph/ThemedBatteryDrawable.kt
@@ -325,7 +325,7 @@ open class ThemedBatteryDrawable(private val context: Context, frameColor: Int)
         return batteryLevel
     }
 
-    override fun onBoundsChange(bounds: Rect?) {
+    override fun onBoundsChange(bounds: Rect) {
         super.onBoundsChange(bounds)
         updateSize()
     }
diff --git a/packages/SystemUI/animation/src/com/android/systemui/animation/DialogLaunchAnimator.kt b/packages/SystemUI/animation/src/com/android/systemui/animation/DialogLaunchAnimator.kt
index 37b1ee543e463..187d0739b734e 100644
--- a/packages/SystemUI/animation/src/com/android/systemui/animation/DialogLaunchAnimator.kt
+++ b/packages/SystemUI/animation/src/com/android/systemui/animation/DialogLaunchAnimator.kt
@@ -249,7 +249,7 @@ constructor(
         // intent is to launch a dialog from another dialog.
         val animatedParent =
             openedDialogs.firstOrNull {
-                it.dialog.window.decorView.viewRootImpl == controller.viewRoot
+                it.dialog.window?.decorView?.viewRootImpl == controller.viewRoot
             }
         val controller =
             animatedParent?.dialogContentWithBackground?.let {
@@ -336,7 +336,7 @@ constructor(
     ): ActivityLaunchAnimator.Controller? {
         val animatedDialog =
             openedDialogs.firstOrNull {
-                it.dialog.window.decorView.viewRootImpl == view.viewRootImpl
+                it.dialog.window?.decorView?.viewRootImpl == view.viewRootImpl
             }
                 ?: return null
         return createActivityLaunchController(animatedDialog, cujType)
@@ -417,7 +417,7 @@ constructor(
                 animatedDialog.prepareForStackDismiss()
 
                 // Remove the dim.
-                dialog.window.clearFlags(WindowManager.LayoutParams.FLAG_DIM_BEHIND)
+                dialog.window?.clearFlags(WindowManager.LayoutParams.FLAG_DIM_BEHIND)
             }
 
             override fun onLaunchAnimationEnd(isExpandingFullyAbove: Boolean) {
@@ -783,7 +783,7 @@ private class AnimatedDialog(
         }
 
         // Show the background dim.
-        dialog.window.addFlags(WindowManager.LayoutParams.FLAG_DIM_BEHIND)
+        dialog.window?.addFlags(WindowManager.LayoutParams.FLAG_DIM_BEHIND)
 
         startAnimation(
             isLaunching = true,
@@ -863,7 +863,7 @@ private class AnimatedDialog(
             isLaunching = false,
             onLaunchAnimationStart = {
                 // Remove the dim background as soon as we start the animation.
-                dialog.window.clearFlags(WindowManager.LayoutParams.FLAG_DIM_BEHIND)
+                dialog.window?.clearFlags(WindowManager.LayoutParams.FLAG_DIM_BEHIND)
             },
             onLaunchAnimationEnd = {
                 val dialogContentWithBackground = this.dialogContentWithBackground!!
diff --git a/packages/SystemUI/animation/src/com/android/systemui/animation/GhostedViewLaunchAnimatorController.kt b/packages/SystemUI/animation/src/com/android/systemui/animation/GhostedViewLaunchAnimatorController.kt
index 1a03ede98d121..6c4b695ed7094 100644
--- a/packages/SystemUI/animation/src/com/android/systemui/animation/GhostedViewLaunchAnimatorController.kt
+++ b/packages/SystemUI/animation/src/com/android/systemui/animation/GhostedViewLaunchAnimatorController.kt
@@ -206,8 +206,9 @@ constructor(
             return
         }
 
-        backgroundView = FrameLayout(launchContainer.context)
-        launchContainerOverlay.add(backgroundView)
+        backgroundView = FrameLayout(launchContainer.context).also {
+            launchContainerOverlay.add(it)
+        }
 
         // We wrap the ghosted view background and use it to draw the expandable background. Its
         // alpha will be set to 0 as soon as we start drawing the expanding background.
@@ -319,7 +320,7 @@ constructor(
         backgroundDrawable?.wrapped?.alpha = startBackgroundAlpha
 
         GhostView.removeGhost(ghostedView)
-        launchContainerOverlay.remove(backgroundView)
+        backgroundView?.let { launchContainerOverlay.remove(it) }
 
         if (ghostedView is LaunchableView) {
             // Restore the ghosted view visibility.
diff --git a/packages/SystemUI/animation/src/com/android/systemui/animation/LaunchAnimator.kt b/packages/SystemUI/animation/src/com/android/systemui/animation/LaunchAnimator.kt
index 142fd21d4a167..d6eba2e7064d4 100644
--- a/packages/SystemUI/animation/src/com/android/systemui/animation/LaunchAnimator.kt
+++ b/packages/SystemUI/animation/src/com/android/systemui/animation/LaunchAnimator.kt
@@ -283,7 +283,7 @@ class LaunchAnimator(private val timings: Timings, private val interpolators: In
 
         animator.addListener(
             object : AnimatorListenerAdapter() {
-                override fun onAnimationStart(animation: Animator?, isReverse: Boolean) {
+                override fun onAnimationStart(animation: Animator, isReverse: Boolean) {
                     if (DEBUG) {
                         Log.d(TAG, "Animation started")
                     }
@@ -295,7 +295,7 @@ class LaunchAnimator(private val timings: Timings, private val interpolators: In
                     launchContainerOverlay.add(windowBackgroundLayer)
                 }
 
-                override fun onAnimationEnd(animation: Animator?) {
+                override fun onAnimationEnd(animation: Animator) {
                     if (DEBUG) {
                         Log.d(TAG, "Animation ended")
                     }
diff --git a/packages/SystemUI/animation/src/com/android/systemui/animation/TextAnimator.kt b/packages/SystemUI/animation/src/com/android/systemui/animation/TextAnimator.kt
index b555fa5835887..8dc74951d332a 100644
--- a/packages/SystemUI/animation/src/com/android/systemui/animation/TextAnimator.kt
+++ b/packages/SystemUI/animation/src/com/android/systemui/animation/TextAnimator.kt
@@ -42,7 +42,9 @@ interface TypefaceVariantCache {
                 return baseTypeface
             }
 
-            val axes = FontVariationAxis.fromFontVariationSettings(fVar).toMutableList()
+            val axes = FontVariationAxis.fromFontVariationSettings(fVar)
+                ?.toMutableList()
+                ?: mutableListOf()
             axes.removeIf { !baseTypeface.isSupportedAxes(it.getOpenTypeTagValue()) }
             if (axes.isEmpty()) {
                 return baseTypeface
@@ -120,8 +122,8 @@ class TextAnimator(
             }
             addListener(
                 object : AnimatorListenerAdapter() {
-                    override fun onAnimationEnd(animation: Animator?) = textInterpolator.rebase()
-                    override fun onAnimationCancel(animation: Animator?) = textInterpolator.rebase()
+                    override fun onAnimationEnd(animation: Animator) = textInterpolator.rebase()
+                    override fun onAnimationCancel(animation: Animator) = textInterpolator.rebase()
                 }
             )
         }
@@ -302,11 +304,11 @@ class TextAnimator(
             if (onAnimationEnd != null) {
                 val listener =
                     object : AnimatorListenerAdapter() {
-                        override fun onAnimationEnd(animation: Animator?) {
+                        override fun onAnimationEnd(animation: Animator) {
                             onAnimationEnd.run()
                             animator.removeListener(this)
                         }
-                        override fun onAnimationCancel(animation: Animator?) {
+                        override fun onAnimationCancel(animation: Animator) {
                             animator.removeListener(this)
                         }
                     }
diff --git a/packages/SystemUI/animation/src/com/android/systemui/animation/ViewHierarchyAnimator.kt b/packages/SystemUI/animation/src/com/android/systemui/animation/ViewHierarchyAnimator.kt
index 38b99cc5f5eef..bd3706e1aff34 100644
--- a/packages/SystemUI/animation/src/com/android/systemui/animation/ViewHierarchyAnimator.kt
+++ b/packages/SystemUI/animation/src/com/android/systemui/animation/ViewHierarchyAnimator.kt
@@ -1046,7 +1046,7 @@ class ViewHierarchyAnimator {
                         }
                     }
 
-                    override fun onAnimationCancel(animation: Animator?) {
+                    override fun onAnimationCancel(animation: Animator) {
                         cancelled = true
                     }
                 }
diff --git a/packages/SystemUI/plugin/src/com/android/systemui/plugins/WeatherData.kt b/packages/SystemUI/plugin/src/com/android/systemui/plugins/WeatherData.kt
index f83fa33caa040..affb76b79d2e9 100644
--- a/packages/SystemUI/plugin/src/com/android/systemui/plugins/WeatherData.kt
+++ b/packages/SystemUI/plugin/src/com/android/systemui/plugins/WeatherData.kt
@@ -57,7 +57,7 @@ constructor(
 
         private fun readIntFromBundle(extras: Bundle, key: String): Int? =
             try {
-                extras.getString(key).toInt()
+                extras.getString(key)?.toInt()
             } catch (e: Exception) {
                 null
             }
diff --git a/packages/SystemUI/shared/src/com/android/systemui/shared/system/ActivityManagerKt.kt b/packages/SystemUI/shared/src/com/android/systemui/shared/system/ActivityManagerKt.kt
index c1429335292f5..5edd283bf131a 100644
--- a/packages/SystemUI/shared/src/com/android/systemui/shared/system/ActivityManagerKt.kt
+++ b/packages/SystemUI/shared/src/com/android/systemui/shared/system/ActivityManagerKt.kt
@@ -27,6 +27,6 @@ object ActivityManagerKt {
      */
     fun ActivityManager.isInForeground(packageName: String): Boolean {
         val tasks: List<ActivityManager.RunningTaskInfo> = getRunningTasks(1)
-        return tasks.isNotEmpty() && packageName == tasks[0].topActivity.packageName
+        return tasks.isNotEmpty() && packageName == tasks[0].topActivity?.packageName
     }
 }
diff --git a/packages/SystemUI/shared/src/com/android/systemui/shared/system/smartspace/SmartspaceState.kt b/packages/SystemUI/shared/src/com/android/systemui/shared/system/smartspace/SmartspaceState.kt
index d7e61d60aa55a..ebc57d2f8af7a 100644
--- a/packages/SystemUI/shared/src/com/android/systemui/shared/system/smartspace/SmartspaceState.kt
+++ b/packages/SystemUI/shared/src/com/android/systemui/shared/system/smartspace/SmartspaceState.kt
@@ -31,15 +31,15 @@ class SmartspaceState() : Parcelable {
     var visibleOnScreen = false
 
     constructor(parcel: Parcel) : this() {
-        this.boundsOnScreen = parcel.readParcelable(Rect::javaClass.javaClass.classLoader)
+        this.boundsOnScreen = parcel.readParcelable(Rect::javaClass.javaClass.classLoader) ?: Rect()
         this.selectedPage = parcel.readInt()
         this.visibleOnScreen = parcel.readBoolean()
     }
 
-    override fun writeToParcel(dest: Parcel?, flags: Int) {
-        dest?.writeParcelable(boundsOnScreen, 0)
-        dest?.writeInt(selectedPage)
-        dest?.writeBoolean(visibleOnScreen)
+    override fun writeToParcel(dest: Parcel, flags: Int) {
+        dest.writeParcelable(boundsOnScreen, 0)
+        dest.writeInt(selectedPage)
+        dest.writeBoolean(visibleOnScreen)
     }
 
     override fun describeContents(): Int {
diff --git a/packages/SystemUI/shared/src/com/android/systemui/unfold/util/NaturalRotationUnfoldProgressProvider.kt b/packages/SystemUI/shared/src/com/android/systemui/unfold/util/NaturalRotationUnfoldProgressProvider.kt
index aca9907fec1bc..dac130d684bd2 100644
--- a/packages/SystemUI/shared/src/com/android/systemui/unfold/util/NaturalRotationUnfoldProgressProvider.kt
+++ b/packages/SystemUI/shared/src/com/android/systemui/unfold/util/NaturalRotationUnfoldProgressProvider.kt
@@ -39,7 +39,7 @@ class NaturalRotationUnfoldProgressProvider(
 
     fun init() {
         rotationChangeProvider.addCallback(rotationListener)
-        rotationListener.onRotationChanged(context.display.rotation)
+        context.display?.rotation?.let { rotationListener.onRotationChanged(it) }
     }
 
     private val rotationListener = RotationListener { rotation ->
diff --git a/packages/SystemUI/src/com/android/keyguard/BouncerKeyguardMessageArea.kt b/packages/SystemUI/src/com/android/keyguard/BouncerKeyguardMessageArea.kt
index 78a5c98f45c88..495367b691237 100644
--- a/packages/SystemUI/src/com/android/keyguard/BouncerKeyguardMessageArea.kt
+++ b/packages/SystemUI/src/com/android/keyguard/BouncerKeyguardMessageArea.kt
@@ -105,7 +105,7 @@ open class BouncerKeyguardMessageArea(context: Context?, attrs: AttributeSet?) :
 
         hideAnimator.addListener(
             object : AnimatorListenerAdapter() {
-                override fun onAnimationEnd(animation: Animator?) {
+                override fun onAnimationEnd(animation: Animator) {
                     super@BouncerKeyguardMessageArea.setMessage(msg, animate)
                 }
             }
@@ -118,7 +118,7 @@ open class BouncerKeyguardMessageArea(context: Context?, attrs: AttributeSet?) :
 
         showAnimator.addListener(
             object : AnimatorListenerAdapter() {
-                override fun onAnimationEnd(animation: Animator?) {
+                override fun onAnimationEnd(animation: Animator) {
                     textAboutToShow = null
                 }
             }
diff --git a/packages/SystemUI/src/com/android/keyguard/ClockEventController.kt b/packages/SystemUI/src/com/android/keyguard/ClockEventController.kt
index 4a6e53d304f42..4f4eec60a117b 100644
--- a/packages/SystemUI/src/com/android/keyguard/ClockEventController.kt
+++ b/packages/SystemUI/src/com/android/keyguard/ClockEventController.kt
@@ -144,7 +144,7 @@ constructor(
                 smallClockOnAttachStateChangeListener =
                     object : OnAttachStateChangeListener {
                         var pastVisibility: Int? = null
-                        override fun onViewAttachedToWindow(view: View?) {
+                        override fun onViewAttachedToWindow(view: View) {
                             value.events.onTimeFormatChanged(DateFormat.is24HourFormat(context))
                             if (view != null) {
                                 smallClockFrame = view.parent as FrameLayout
@@ -168,7 +168,7 @@ constructor(
                             }
                         }
 
-                        override fun onViewDetachedFromWindow(p0: View?) {
+                        override fun onViewDetachedFromWindow(p0: View) {
                             smallClockFrame?.viewTreeObserver
                                     ?.removeOnGlobalLayoutListener(onGlobalLayoutListener)
                         }
@@ -178,10 +178,10 @@ constructor(
 
                 largeClockOnAttachStateChangeListener =
                     object : OnAttachStateChangeListener {
-                        override fun onViewAttachedToWindow(p0: View?) {
+                        override fun onViewAttachedToWindow(p0: View) {
                             value.events.onTimeFormatChanged(DateFormat.is24HourFormat(context))
                         }
-                        override fun onViewDetachedFromWindow(p0: View?) {
+                        override fun onViewDetachedFromWindow(p0: View) {
                         }
                 }
                 value.largeClock.view
diff --git a/packages/SystemUI/src/com/android/systemui/biometrics/AuthRippleController.kt b/packages/SystemUI/src/com/android/systemui/biometrics/AuthRippleController.kt
index 946ddba6a3414..ea9fe5fce53e5 100644
--- a/packages/SystemUI/src/com/android/systemui/biometrics/AuthRippleController.kt
+++ b/packages/SystemUI/src/com/android/systemui/biometrics/AuthRippleController.kt
@@ -230,7 +230,7 @@ class AuthRippleController @Inject constructor(
                         lightRevealScrim.revealAmount = animator.animatedValue as Float
                     }
                     addListener(object : AnimatorListenerAdapter() {
-                        override fun onAnimationEnd(animation: Animator?) {
+                        override fun onAnimationEnd(animation: Animator) {
                             // Reset light reveal scrim to the default, so the CentralSurfaces
                             // can handle any subsequent light reveal changes
                             // (ie: from dozing changes)
diff --git a/packages/SystemUI/src/com/android/systemui/biometrics/AuthRippleView.kt b/packages/SystemUI/src/com/android/systemui/biometrics/AuthRippleView.kt
index 5ede16d221b7e..4c2dc41fb759a 100644
--- a/packages/SystemUI/src/com/android/systemui/biometrics/AuthRippleView.kt
+++ b/packages/SystemUI/src/com/android/systemui/biometrics/AuthRippleView.kt
@@ -147,12 +147,12 @@ class AuthRippleView(context: Context?, attrs: AttributeSet?) : View(context, at
             retractDwellAnimator = AnimatorSet().apply {
                 playTogether(retractDwellRippleAnimator, retractAlphaAnimator)
                 addListener(object : AnimatorListenerAdapter() {
-                    override fun onAnimationStart(animation: Animator?) {
+                    override fun onAnimationStart(animation: Animator) {
                         dwellPulseOutAnimator?.cancel()
                         drawDwell = true
                     }
 
-                    override fun onAnimationEnd(animation: Animator?) {
+                    override fun onAnimationEnd(animation: Animator) {
                         drawDwell = false
                         resetDwellAlpha()
                     }
@@ -182,13 +182,13 @@ class AuthRippleView(context: Context?, attrs: AttributeSet?) : View(context, at
                     invalidate()
                 }
                 addListener(object : AnimatorListenerAdapter() {
-                    override fun onAnimationStart(animation: Animator?) {
+                    override fun onAnimationStart(animation: Animator) {
                         retractDwellAnimator?.cancel()
                         dwellPulseOutAnimator?.cancel()
                         drawDwell = true
                     }
 
-                    override fun onAnimationEnd(animation: Animator?) {
+                    override fun onAnimationEnd(animation: Animator) {
                         drawDwell = false
                         resetDwellAlpha()
                     }
@@ -239,14 +239,14 @@ class AuthRippleView(context: Context?, attrs: AttributeSet?) : View(context, at
                     expandDwellRippleAnimator
             )
             addListener(object : AnimatorListenerAdapter() {
-                override fun onAnimationStart(animation: Animator?) {
+                override fun onAnimationStart(animation: Animator) {
                     retractDwellAnimator?.cancel()
                     fadeDwellAnimator?.cancel()
                     visibility = VISIBLE
                     drawDwell = true
                 }
 
-                override fun onAnimationEnd(animation: Animator?) {
+                override fun onAnimationEnd(animation: Animator) {
                     drawDwell = false
                 }
             })
@@ -273,12 +273,12 @@ class AuthRippleView(context: Context?, attrs: AttributeSet?) : View(context, at
 
         unlockedRippleAnimator = rippleAnimator.apply {
             addListener(object : AnimatorListenerAdapter() {
-                override fun onAnimationStart(animation: Animator?) {
+                override fun onAnimationStart(animation: Animator) {
                     drawRipple = true
                     visibility = VISIBLE
                 }
 
-                override fun onAnimationEnd(animation: Animator?) {
+                override fun onAnimationEnd(animation: Animator) {
                     onAnimationEnd?.run()
                     drawRipple = false
                     visibility = GONE
@@ -327,7 +327,7 @@ class AuthRippleView(context: Context?, attrs: AttributeSet?) : View(context, at
         }
     }
 
-    override fun onDraw(canvas: Canvas?) {
+    override fun onDraw(canvas: Canvas) {
         // To reduce overdraw, we mask the effect to a circle whose radius is big enough to cover
         // the active effect area. Values here should be kept in sync with the
         // animation implementation in the ripple shader. (Twice bigger)
diff --git a/packages/SystemUI/src/com/android/systemui/biometrics/FaceAuthAccessibilityDelegate.kt b/packages/SystemUI/src/com/android/systemui/biometrics/FaceAuthAccessibilityDelegate.kt
index b9fa24022ad55..a24a47bb44df3 100644
--- a/packages/SystemUI/src/com/android/systemui/biometrics/FaceAuthAccessibilityDelegate.kt
+++ b/packages/SystemUI/src/com/android/systemui/biometrics/FaceAuthAccessibilityDelegate.kt
@@ -40,7 +40,7 @@ constructor(
     private val keyguardUpdateMonitor: KeyguardUpdateMonitor,
     private val faceAuthInteractor: KeyguardFaceAuthInteractor,
 ) : View.AccessibilityDelegate() {
-    override fun onInitializeAccessibilityNodeInfo(host: View?, info: AccessibilityNodeInfo) {
+    override fun onInitializeAccessibilityNodeInfo(host: View, info: AccessibilityNodeInfo) {
         super.onInitializeAccessibilityNodeInfo(host, info)
         if (keyguardUpdateMonitor.shouldListenForFace()) {
             val clickActionToRetryFace =
@@ -52,7 +52,7 @@ constructor(
         }
     }
 
-    override fun performAccessibilityAction(host: View?, action: Int, args: Bundle?): Boolean {
+    override fun performAccessibilityAction(host: View, action: Int, args: Bundle?): Boolean {
         return if (action == AccessibilityNodeInfo.AccessibilityAction.ACTION_CLICK.id) {
             keyguardUpdateMonitor.requestFaceAuth(FaceAuthApiRequestReason.ACCESSIBILITY_ACTION)
             faceAuthInteractor.onAccessibilityAction()
diff --git a/packages/SystemUI/src/com/android/systemui/biometrics/SideFpsController.kt b/packages/SystemUI/src/com/android/systemui/biometrics/SideFpsController.kt
index 7f696fd1eeae9..eb6864d91ba43 100644
--- a/packages/SystemUI/src/com/android/systemui/biometrics/SideFpsController.kt
+++ b/packages/SystemUI/src/com/android/systemui/biometrics/SideFpsController.kt
@@ -119,7 +119,7 @@ constructor(
     private var overlayView: View? = null
         set(value) {
             field?.let { oldView ->
-                val lottie = oldView.findViewById(R.id.sidefps_animation) as LottieAnimationView
+                val lottie = oldView.requireViewById(R.id.sidefps_animation) as LottieAnimationView
                 lottie.pauseAnimation()
                 windowManager.removeView(oldView)
                 orientationListener.disable()
@@ -274,7 +274,7 @@ constructor(
             }
         overlayOffsets = offsets
 
-        val lottie = view.findViewById(R.id.sidefps_animation) as LottieAnimationView
+        val lottie = view.requireViewById(R.id.sidefps_animation) as LottieAnimationView
         view.rotation =
             display.asSideFpsAnimationRotation(
                 offsets.isYAligned(),
diff --git a/packages/SystemUI/src/com/android/systemui/biometrics/UdfpsFpmEmptyView.kt b/packages/SystemUI/src/com/android/systemui/biometrics/UdfpsFpmEmptyView.kt
index 8352d0aeab350..5dafa61f9a27f 100644
--- a/packages/SystemUI/src/com/android/systemui/biometrics/UdfpsFpmEmptyView.kt
+++ b/packages/SystemUI/src/com/android/systemui/biometrics/UdfpsFpmEmptyView.kt
@@ -38,7 +38,8 @@ class UdfpsFpmEmptyView(
     override fun getDrawable(): UdfpsDrawable = fingerprintDrawable
 
     fun updateAccessibilityViewLocation(sensorBounds: Rect) {
-        val fingerprintAccessibilityView: View = findViewById(R.id.udfps_enroll_accessibility_view)
+        val fingerprintAccessibilityView: View =
+            requireViewById(R.id.udfps_enroll_accessibility_view)
         val params: ViewGroup.LayoutParams = fingerprintAccessibilityView.layoutParams
         params.width = sensorBounds.width()
         params.height = sensorBounds.height()
diff --git a/packages/SystemUI/src/com/android/systemui/biometrics/UdfpsKeyguardAccessibilityDelegate.kt b/packages/SystemUI/src/com/android/systemui/biometrics/UdfpsKeyguardAccessibilityDelegate.kt
index fb7b56e129962..84978790f49cd 100644
--- a/packages/SystemUI/src/com/android/systemui/biometrics/UdfpsKeyguardAccessibilityDelegate.kt
+++ b/packages/SystemUI/src/com/android/systemui/biometrics/UdfpsKeyguardAccessibilityDelegate.kt
@@ -33,7 +33,7 @@ constructor(
     @Main private val resources: Resources,
     private val keyguardViewManager: StatusBarKeyguardViewManager,
 ) : View.AccessibilityDelegate() {
-    override fun onInitializeAccessibilityNodeInfo(host: View?, info: AccessibilityNodeInfo) {
+    override fun onInitializeAccessibilityNodeInfo(host: View, info: AccessibilityNodeInfo) {
         super.onInitializeAccessibilityNodeInfo(host, info)
         val clickAction =
             AccessibilityNodeInfo.AccessibilityAction(
@@ -43,7 +43,7 @@ constructor(
         info.addAction(clickAction)
     }
 
-    override fun performAccessibilityAction(host: View?, action: Int, args: Bundle?): Boolean {
+    override fun performAccessibilityAction(host: View, action: Int, args: Bundle?): Boolean {
         // when an a11y service is enabled, double tapping on the fingerprint sensor should
         // show the primary bouncer
         return if (action == AccessibilityNodeInfo.AccessibilityAction.ACTION_CLICK.id) {
diff --git a/packages/SystemUI/src/com/android/systemui/biometrics/UdfpsKeyguardViewControllerLegacy.kt b/packages/SystemUI/src/com/android/systemui/biometrics/UdfpsKeyguardViewControllerLegacy.kt
index db30a55ea1e13..e3fd3ce1bcbfc 100644
--- a/packages/SystemUI/src/com/android/systemui/biometrics/UdfpsKeyguardViewControllerLegacy.kt
+++ b/packages/SystemUI/src/com/android/systemui/biometrics/UdfpsKeyguardViewControllerLegacy.kt
@@ -306,8 +306,9 @@ constructor(
         activityLaunchAnimator.addListener(activityLaunchAnimatorListener)
         view.mUseExpandedOverlay = useExpandedOverlay
         view.startIconAsyncInflate {
-            (view.findViewById(R.id.udfps_animation_view_internal) as View).accessibilityDelegate =
-                udfpsKeyguardAccessibilityDelegate
+            val animationViewInternal: View =
+                view.requireViewById(R.id.udfps_animation_view_internal)
+            animationViewInternal.accessibilityDelegate = udfpsKeyguardAccessibilityDelegate
         }
     }
 
diff --git a/packages/SystemUI/src/com/android/systemui/biometrics/domain/interactor/CredentialInteractor.kt b/packages/SystemUI/src/com/android/systemui/biometrics/domain/interactor/CredentialInteractor.kt
index 1f1a1b5c83bd5..2a026675adcb3 100644
--- a/packages/SystemUI/src/com/android/systemui/biometrics/domain/interactor/CredentialInteractor.kt
+++ b/packages/SystemUI/src/com/android/systemui/biometrics/domain/interactor/CredentialInteractor.kt
@@ -89,7 +89,7 @@ constructor(
                 )
             val hat = gkResponse.gatekeeperHAT
             lockPatternUtils.removeGatekeeperPasswordHandle(pwHandle)
-            emit(CredentialStatus.Success.Verified(hat))
+            emit(CredentialStatus.Success.Verified(checkNotNull(hat)))
         } else if (response.timeout > 0) {
             // if requests are being throttled, update the error message every
             // second until the temporary lock has expired
@@ -226,8 +226,7 @@ private fun Context.getLastAttemptBeforeWipeProfileMessage(
             is BiometricPromptRequest.Credential.Password ->
                 DevicePolicyResources.Strings.SystemUi.BIOMETRIC_DIALOG_WORK_PASSWORD_LAST_ATTEMPT
         }
-    return devicePolicyManager.resources.getString(id) {
-        // use fallback a string if not found
+    val getFallbackString = {
         val defaultId =
             when (request) {
                 is BiometricPromptRequest.Credential.Pin ->
@@ -239,6 +238,8 @@ private fun Context.getLastAttemptBeforeWipeProfileMessage(
             }
         getString(defaultId)
     }
+
+    return devicePolicyManager.resources?.getString(id, getFallbackString) ?: getFallbackString()
 }
 
 private fun Context.getLastAttemptBeforeWipeUserMessage(
@@ -266,8 +267,8 @@ private fun Context.getNowWipingMessage(
                 DevicePolicyResources.Strings.SystemUi.BIOMETRIC_DIALOG_WORK_LOCK_FAILED_ATTEMPTS
             else -> DevicePolicyResources.UNDEFINED
         }
-    return devicePolicyManager.resources.getString(id) {
-        // use fallback a string if not found
+
+    val getFallbackString = {
         val defaultId =
             when (userType) {
                 UserType.PRIMARY ->
@@ -279,4 +280,6 @@ private fun Context.getNowWipingMessage(
             }
         getString(defaultId)
     }
+
+    return devicePolicyManager.resources?.getString(id, getFallbackString) ?: getFallbackString()
 }
diff --git a/packages/SystemUI/src/com/android/systemui/biometrics/ui/CredentialPasswordView.kt b/packages/SystemUI/src/com/android/systemui/biometrics/ui/CredentialPasswordView.kt
index a3f34ce7471de..b940ec85efbf5 100644
--- a/packages/SystemUI/src/com/android/systemui/biometrics/ui/CredentialPasswordView.kt
+++ b/packages/SystemUI/src/com/android/systemui/biometrics/ui/CredentialPasswordView.kt
@@ -122,7 +122,7 @@ class CredentialPasswordView(context: Context, attrs: AttributeSet?) :
                 titleView.ellipsize = TextUtils.TruncateAt.MARQUEE
                 titleView.marqueeRepeatLimit = -1
                 // select to enable marquee unless a screen reader is enabled
-                titleView.isSelected = accessibilityManager.shouldMarquee()
+                titleView.isSelected = accessibilityManager?.shouldMarquee() ?: false
             } else {
                 titleView.isSingleLine = false
                 titleView.ellipsize = null
diff --git a/packages/SystemUI/src/com/android/systemui/biometrics/ui/binder/BiometricViewBinder.kt b/packages/SystemUI/src/com/android/systemui/biometrics/ui/binder/BiometricViewBinder.kt
index a4cd3fa88e666..75b26f8598098 100644
--- a/packages/SystemUI/src/com/android/systemui/biometrics/ui/binder/BiometricViewBinder.kt
+++ b/packages/SystemUI/src/com/android/systemui/biometrics/ui/binder/BiometricViewBinder.kt
@@ -85,9 +85,9 @@ object BiometricViewBinder {
         val textColorHint =
             view.resources.getColor(R.color.biometric_dialog_gray, view.context.theme)
 
-        val titleView = view.findViewById<TextView>(R.id.title)
-        val subtitleView = view.findViewById<TextView>(R.id.subtitle)
-        val descriptionView = view.findViewById<TextView>(R.id.description)
+        val titleView = view.requireViewById<TextView>(R.id.title)
+        val subtitleView = view.requireViewById<TextView>(R.id.subtitle)
+        val descriptionView = view.requireViewById<TextView>(R.id.description)
 
         // set selected to enable marquee unless a screen reader is enabled
         titleView.isSelected =
@@ -96,18 +96,18 @@ object BiometricViewBinder {
             !accessibilityManager.isEnabled || !accessibilityManager.isTouchExplorationEnabled
         descriptionView.movementMethod = ScrollingMovementMethod()
 
-        val iconViewOverlay = view.findViewById<LottieAnimationView>(R.id.biometric_icon_overlay)
-        val iconView = view.findViewById<LottieAnimationView>(R.id.biometric_icon)
-        val indicatorMessageView = view.findViewById<TextView>(R.id.indicator)
+        val iconViewOverlay = view.requireViewById<LottieAnimationView>(R.id.biometric_icon_overlay)
+        val iconView = view.requireViewById<LottieAnimationView>(R.id.biometric_icon)
+        val indicatorMessageView = view.requireViewById<TextView>(R.id.indicator)
 
         // Negative-side (left) buttons
-        val negativeButton = view.findViewById<Button>(R.id.button_negative)
-        val cancelButton = view.findViewById<Button>(R.id.button_cancel)
-        val credentialFallbackButton = view.findViewById<Button>(R.id.button_use_credential)
+        val negativeButton = view.requireViewById<Button>(R.id.button_negative)
+        val cancelButton = view.requireViewById<Button>(R.id.button_cancel)
+        val credentialFallbackButton = view.requireViewById<Button>(R.id.button_use_credential)
 
         // Positive-side (right) buttons
-        val confirmationButton = view.findViewById<Button>(R.id.button_confirm)
-        val retryButton = view.findViewById<Button>(R.id.button_try_again)
+        val confirmationButton = view.requireViewById<Button>(R.id.button_confirm)
+        val retryButton = view.requireViewById<Button>(R.id.button_try_again)
 
         // TODO(b/251476085): temporary workaround for the unsafe callbacks & legacy controllers
         val adapter =
diff --git a/packages/SystemUI/src/com/android/systemui/biometrics/ui/binder/BiometricViewSizeBinder.kt b/packages/SystemUI/src/com/android/systemui/biometrics/ui/binder/BiometricViewSizeBinder.kt
index 1a286cf57982c..370b36bcaec26 100644
--- a/packages/SystemUI/src/com/android/systemui/biometrics/ui/binder/BiometricViewSizeBinder.kt
+++ b/packages/SystemUI/src/com/android/systemui/biometrics/ui/binder/BiometricViewSizeBinder.kt
@@ -72,7 +72,7 @@ object BiometricViewSizeBinder {
             }
         }
 
-        val iconHolderView = view.findViewById<View>(R.id.biometric_icon_frame)
+        val iconHolderView = view.requireViewById<View>(R.id.biometric_icon_frame)
         val iconPadding = view.resources.getDimension(R.dimen.biometric_dialog_icon_padding)
         val fullSizeYOffset =
             view.resources.getDimension(R.dimen.biometric_dialog_medium_to_large_translation_offset)
@@ -205,7 +205,7 @@ object BiometricViewSizeBinder {
 }
 
 private fun View.isLandscape(): Boolean {
-    val r = context.display.rotation
+    val r = context.display?.rotation
     return r == Surface.ROTATION_90 || r == Surface.ROTATION_270
 }
 
diff --git a/packages/SystemUI/src/com/android/systemui/charging/WiredChargingRippleController.kt b/packages/SystemUI/src/com/android/systemui/charging/WiredChargingRippleController.kt
index 5ca36ab39dba6..ddb0974919881 100644
--- a/packages/SystemUI/src/com/android/systemui/charging/WiredChargingRippleController.kt
+++ b/packages/SystemUI/src/com/android/systemui/charging/WiredChargingRippleController.kt
@@ -156,9 +156,9 @@ class WiredChargingRippleController @Inject constructor(
         }
         windowLayoutParams.packageName = context.opPackageName
         rippleView.addOnAttachStateChangeListener(object : View.OnAttachStateChangeListener {
-            override fun onViewDetachedFromWindow(view: View?) {}
+            override fun onViewDetachedFromWindow(view: View) {}
 
-            override fun onViewAttachedToWindow(view: View?) {
+            override fun onViewAttachedToWindow(view: View) {
                 layoutRipple()
                 rippleView.startRipple(Runnable {
                     windowManager.removeView(rippleView)
@@ -176,7 +176,7 @@ class WiredChargingRippleController @Inject constructor(
         val height = bounds.height()
         val maxDiameter = Integer.max(width, height) * 2f
         rippleView.setMaxSize(maxDiameter, maxDiameter)
-        when (context.display.rotation) {
+        when (context.display?.rotation) {
             Surface.ROTATION_0 -> {
                 rippleView.setCenter(
                         width * normalizedPortPosX, height * normalizedPortPosY)
diff --git a/packages/SystemUI/src/com/android/systemui/classifier/FalsingA11yDelegate.kt b/packages/SystemUI/src/com/android/systemui/classifier/FalsingA11yDelegate.kt
index 63d57cc3fc8d8..a9f3b77ceb5ea 100644
--- a/packages/SystemUI/src/com/android/systemui/classifier/FalsingA11yDelegate.kt
+++ b/packages/SystemUI/src/com/android/systemui/classifier/FalsingA11yDelegate.kt
@@ -29,7 +29,7 @@ import javax.inject.Inject
  */
 class FalsingA11yDelegate @Inject constructor(private val falsingCollector: FalsingCollector) :
     View.AccessibilityDelegate() {
-    override fun performAccessibilityAction(host: View?, action: Int, args: Bundle?): Boolean {
+    override fun performAccessibilityAction(host: View, action: Int, args: Bundle?): Boolean {
         if (action == ACTION_CLICK) {
             falsingCollector.onA11yAction()
         }
diff --git a/packages/SystemUI/src/com/android/systemui/common/ui/data/repository/ConfigurationRepository.kt b/packages/SystemUI/src/com/android/systemui/common/ui/data/repository/ConfigurationRepository.kt
index 3e6ac86e2417a..c0d1951c22ce9 100644
--- a/packages/SystemUI/src/com/android/systemui/common/ui/data/repository/ConfigurationRepository.kt
+++ b/packages/SystemUI/src/com/android/systemui/common/ui/data/repository/ConfigurationRepository.kt
@@ -100,7 +100,7 @@ constructor(
             .stateIn(scope, SharingStarted.WhileSubscribed(), getResolutionScale())
 
     override fun getResolutionScale(): Float {
-        context.display.getDisplayInfo(displayInfo.value)
+        context.display?.getDisplayInfo(displayInfo.value)
         val maxDisplayMode =
             displayUtils.getMaximumResolutionDisplayMode(displayInfo.value.supportedModes)
         maxDisplayMode?.let {
diff --git a/packages/SystemUI/src/com/android/systemui/contrast/ContrastDialog.kt b/packages/SystemUI/src/com/android/systemui/contrast/ContrastDialog.kt
index f17d0f307473d..0b327a19ef819 100644
--- a/packages/SystemUI/src/com/android/systemui/contrast/ContrastDialog.kt
+++ b/packages/SystemUI/src/com/android/systemui/contrast/ContrastDialog.kt
@@ -66,9 +66,9 @@ class ContrastDialog(
 
         contrastButtons =
             mapOf(
-                CONTRAST_LEVEL_STANDARD to findViewById(R.id.contrast_button_standard),
-                CONTRAST_LEVEL_MEDIUM to findViewById(R.id.contrast_button_medium),
-                CONTRAST_LEVEL_HIGH to findViewById(R.id.contrast_button_high)
+                CONTRAST_LEVEL_STANDARD to requireViewById(R.id.contrast_button_standard),
+                CONTRAST_LEVEL_MEDIUM to requireViewById(R.id.contrast_button_medium),
+                CONTRAST_LEVEL_HIGH to requireViewById(R.id.contrast_button_high)
             )
 
         contrastButtons.forEach { (contrastLevel, contrastButton) ->
diff --git a/packages/SystemUI/src/com/android/systemui/controls/controller/ControlsControllerImpl.kt b/packages/SystemUI/src/com/android/systemui/controls/controller/ControlsControllerImpl.kt
index e8c97bf772716..4a534e9cc74d5 100644
--- a/packages/SystemUI/src/com/android/systemui/controls/controller/ControlsControllerImpl.kt
+++ b/packages/SystemUI/src/com/android/systemui/controls/controller/ControlsControllerImpl.kt
@@ -190,7 +190,7 @@ class ControlsControllerImpl @Inject constructor (
                     PREFS_CONTROLS_SEEDING_COMPLETED, mutableSetOf<String>())
                 val servicePackageSet = serviceInfoSet.map { it.packageName }
                 prefs.edit().putStringSet(PREFS_CONTROLS_SEEDING_COMPLETED,
-                    completedSeedingPackageSet.intersect(servicePackageSet)).apply()
+                    completedSeedingPackageSet?.intersect(servicePackageSet) ?: emptySet()).apply()
 
                 var changed = false
                 favoriteComponentSet.subtract(serviceInfoSet).forEach {
diff --git a/packages/SystemUI/src/com/android/systemui/controls/management/ControlsFavoritingActivity.kt b/packages/SystemUI/src/com/android/systemui/controls/management/ControlsFavoritingActivity.kt
index 23721c93508b7..8bae6674aa11f 100644
--- a/packages/SystemUI/src/com/android/systemui/controls/management/ControlsFavoritingActivity.kt
+++ b/packages/SystemUI/src/com/android/systemui/controls/management/ControlsFavoritingActivity.kt
@@ -193,7 +193,7 @@ open class ControlsFavoritingActivity @Inject constructor(
 
                         ControlsAnimations.enterAnimation(pageIndicator).apply {
                             addListener(object : AnimatorListenerAdapter() {
-                                override fun onAnimationEnd(animation: Animator?) {
+                                override fun onAnimationEnd(animation: Animator) {
                                     // Position the tooltip if necessary after animations are complete
                                     // so we can get the position on screen. The tooltip is not
                                     // rooted in the layout root.
diff --git a/packages/SystemUI/src/com/android/systemui/controls/ui/ChallengeDialogs.kt b/packages/SystemUI/src/com/android/systemui/controls/ui/ChallengeDialogs.kt
index ff55b76d4db79..a13f717bc77d7 100644
--- a/packages/SystemUI/src/com/android/systemui/controls/ui/ChallengeDialogs.kt
+++ b/packages/SystemUI/src/com/android/systemui/controls/ui/ChallengeDialogs.kt
@@ -106,10 +106,8 @@ object ChallengeDialogs {
                 }
             )
 
-            getWindow().apply {
-                setType(WINDOW_TYPE)
-                setSoftInputMode(WindowManager.LayoutParams.SOFT_INPUT_STATE_VISIBLE)
-            }
+            window?.setType(WINDOW_TYPE)
+            window?.setSoftInputMode(WindowManager.LayoutParams.SOFT_INPUT_STATE_VISIBLE)
             setOnShowListener(DialogInterface.OnShowListener { _ ->
                 val editText = requireViewById<EditText>(R.id.controls_pin_input)
                 editText.setHint(instructions)
@@ -153,9 +151,7 @@ object ChallengeDialogs {
             )
         }
         return builder.create().apply {
-            getWindow().apply {
-                setType(WINDOW_TYPE)
-            }
+            window?.setType(WINDOW_TYPE)
         }
     }
 
diff --git a/packages/SystemUI/src/com/android/systemui/controls/ui/ControlViewHolder.kt b/packages/SystemUI/src/com/android/systemui/controls/ui/ControlViewHolder.kt
index c04bc8792223d..abe3423208582 100644
--- a/packages/SystemUI/src/com/android/systemui/controls/ui/ControlViewHolder.kt
+++ b/packages/SystemUI/src/com/android/systemui/controls/ui/ControlViewHolder.kt
@@ -384,7 +384,7 @@ class ControlViewHolder(
                 )
             }
             addListener(object : AnimatorListenerAdapter() {
-                override fun onAnimationEnd(animation: Animator?) {
+                override fun onAnimationEnd(animation: Animator) {
                     stateAnimator = null
                 }
             })
@@ -438,7 +438,7 @@ class ControlViewHolder(
                 duration = 200L
                 interpolator = Interpolators.LINEAR
                 addListener(object : AnimatorListenerAdapter() {
-                    override fun onAnimationEnd(animation: Animator?) {
+                    override fun onAnimationEnd(animation: Animator) {
                         statusRowUpdater.invoke()
                     }
                 })
@@ -450,7 +450,7 @@ class ControlViewHolder(
             statusAnimator = AnimatorSet().apply {
                 playSequentially(fadeOut, fadeIn)
                 addListener(object : AnimatorListenerAdapter() {
-                    override fun onAnimationEnd(animation: Animator?) {
+                    override fun onAnimationEnd(animation: Animator) {
                         status.alpha = STATUS_ALPHA_ENABLED
                         statusAnimator = null
                     }
diff --git a/packages/SystemUI/src/com/android/systemui/controls/ui/DetailDialog.kt b/packages/SystemUI/src/com/android/systemui/controls/ui/DetailDialog.kt
index be50a1468f078..98f17f409184f 100644
--- a/packages/SystemUI/src/com/android/systemui/controls/ui/DetailDialog.kt
+++ b/packages/SystemUI/src/com/android/systemui/controls/ui/DetailDialog.kt
@@ -132,8 +132,8 @@ class DetailDialog(
 
     init {
         // To pass touches to the task inside TaskView.
-        window.addFlags(WindowManager.LayoutParams.FLAG_NOT_TOUCH_MODAL)
-        window.addPrivateFlags(WindowManager.LayoutParams.PRIVATE_FLAG_TRUSTED_OVERLAY)
+        window?.addFlags(WindowManager.LayoutParams.FLAG_NOT_TOUCH_MODAL)
+        window?.addPrivateFlags(WindowManager.LayoutParams.PRIVATE_FLAG_TRUSTED_OVERLAY)
 
         setContentView(R.layout.controls_detail_dialog)
 
@@ -182,7 +182,7 @@ class DetailDialog(
         }
 
         // consume all insets to achieve slide under effect
-        window.getDecorView().setOnApplyWindowInsetsListener {
+        checkNotNull(window).decorView.setOnApplyWindowInsetsListener {
             v: View, insets: WindowInsets ->
                 val l = v.getPaddingLeft()
                 val r = v.getPaddingRight()
@@ -202,7 +202,7 @@ class DetailDialog(
     }
 
     fun getTaskViewBounds(): Rect {
-        val wm = context.getSystemService(WindowManager::class.java)
+        val wm = checkNotNull(context.getSystemService(WindowManager::class.java))
         val windowMetrics = wm.getCurrentWindowMetrics()
         val rect = windowMetrics.bounds
         val metricInsets = windowMetrics.windowInsets
diff --git a/packages/SystemUI/src/com/android/systemui/controls/ui/RenderInfo.kt b/packages/SystemUI/src/com/android/systemui/controls/ui/RenderInfo.kt
index ad2b785ea5c56..dbbda9aad5187 100644
--- a/packages/SystemUI/src/com/android/systemui/controls/ui/RenderInfo.kt
+++ b/packages/SystemUI/src/com/android/systemui/controls/ui/RenderInfo.kt
@@ -67,7 +67,8 @@ data class RenderInfo(
                     iconMap.put(resourceId, icon)
                 }
             }
-            return RenderInfo(icon!!.constantState.newDrawable(context.resources), fg, bg)
+            return RenderInfo(
+                checkNotNull(icon?.constantState).newDrawable(context.resources), fg, bg)
         }
 
         fun registerComponentIcon(componentName: ComponentName, icon: Drawable) {
diff --git a/packages/SystemUI/src/com/android/systemui/controls/ui/StatusBehavior.kt b/packages/SystemUI/src/com/android/systemui/controls/ui/StatusBehavior.kt
index 84cda5a541e32..3c2bfa0efc396 100644
--- a/packages/SystemUI/src/com/android/systemui/controls/ui/StatusBehavior.kt
+++ b/packages/SystemUI/src/com/android/systemui/controls/ui/StatusBehavior.kt
@@ -94,10 +94,8 @@ class StatusBehavior : Behavior {
             )
         }
         cvh.visibleDialog = builder.create().apply {
-            getWindow().apply {
-                setType(WindowManager.LayoutParams.TYPE_VOLUME_OVERLAY)
-                show()
-            }
+            window?.setType(WindowManager.LayoutParams.TYPE_VOLUME_OVERLAY)
+            show()
         }
     }
 }
diff --git a/packages/SystemUI/src/com/android/systemui/controls/ui/ToggleRangeBehavior.kt b/packages/SystemUI/src/com/android/systemui/controls/ui/ToggleRangeBehavior.kt
index 1461135d3d3bd..b2c95a63ad728 100644
--- a/packages/SystemUI/src/com/android/systemui/controls/ui/ToggleRangeBehavior.kt
+++ b/packages/SystemUI/src/com/android/systemui/controls/ui/ToggleRangeBehavior.kt
@@ -244,7 +244,7 @@ class ToggleRangeBehavior : Behavior {
                     cvh.clipLayer.level = it.animatedValue as Int
                 }
                 addListener(object : AnimatorListenerAdapter() {
-                    override fun onAnimationEnd(animation: Animator?) {
+                    override fun onAnimationEnd(animation: Animator) {
                         rangeAnimator = null
                     }
                 })
@@ -335,7 +335,7 @@ class ToggleRangeBehavior : Behavior {
         }
 
         override fun onScroll(
-            e1: MotionEvent,
+            e1: MotionEvent?,
             e2: MotionEvent,
             xDiff: Float,
             yDiff: Float
diff --git a/packages/SystemUI/src/com/android/systemui/display/data/repository/DisplayMetricsRepository.kt b/packages/SystemUI/src/com/android/systemui/display/data/repository/DisplayMetricsRepository.kt
index bcfeeb9eaadd0..cef45dcae43ef 100644
--- a/packages/SystemUI/src/com/android/systemui/display/data/repository/DisplayMetricsRepository.kt
+++ b/packages/SystemUI/src/com/android/systemui/display/data/repository/DisplayMetricsRepository.kt
@@ -51,7 +51,7 @@ constructor(
                 val callback =
                     object : ConfigurationController.ConfigurationListener {
                         override fun onConfigChanged(newConfig: Configuration?) {
-                            context.display.getMetrics(displayMetricsHolder)
+                            context.display?.getMetrics(displayMetricsHolder)
                             trySend(displayMetricsHolder)
                         }
                     }
diff --git a/packages/SystemUI/src/com/android/systemui/keyboard/backlight/ui/view/KeyboardBacklightDialog.kt b/packages/SystemUI/src/com/android/systemui/keyboard/backlight/ui/view/KeyboardBacklightDialog.kt
index 70783418ddb45..b5b56b2b2108e 100644
--- a/packages/SystemUI/src/com/android/systemui/keyboard/backlight/ui/view/KeyboardBacklightDialog.kt
+++ b/packages/SystemUI/src/com/android/systemui/keyboard/backlight/ui/view/KeyboardBacklightDialog.kt
@@ -161,7 +161,7 @@ class KeyboardBacklightDialog(
     }
 
     private fun updateIconTile() {
-        val iconTile = rootView.findViewById(BACKLIGHT_ICON_ID) as ImageView
+        val iconTile = rootView.requireViewById(BACKLIGHT_ICON_ID) as ImageView
         val backgroundDrawable = iconTile.background as ShapeDrawable
         if (currentLevel == 0) {
             iconTile.setColorFilter(dimmedIconColor)
diff --git a/packages/SystemUI/src/com/android/systemui/keyguard/data/quickaffordance/QuickAccessWalletKeyguardQuickAffordanceConfig.kt b/packages/SystemUI/src/com/android/systemui/keyguard/data/quickaffordance/QuickAccessWalletKeyguardQuickAffordanceConfig.kt
index c019d21e00eda..5d7a3d432dcb5 100644
--- a/packages/SystemUI/src/com/android/systemui/keyguard/data/quickaffordance/QuickAccessWalletKeyguardQuickAffordanceConfig.kt
+++ b/packages/SystemUI/src/com/android/systemui/keyguard/data/quickaffordance/QuickAccessWalletKeyguardQuickAffordanceConfig.kt
@@ -59,7 +59,7 @@ constructor(
         conflatedCallbackFlow {
             val callback =
                 object : QuickAccessWalletClient.OnWalletCardsRetrievedCallback {
-                    override fun onWalletCardsRetrieved(response: GetWalletCardsResponse?) {
+                    override fun onWalletCardsRetrieved(response: GetWalletCardsResponse) {
                         val hasCards = response?.walletCards?.isNotEmpty() == true
                         trySendWithFailureLogging(
                             state(
@@ -71,7 +71,7 @@ constructor(
                         )
                     }
 
-                    override fun onWalletCardRetrievalError(error: GetWalletCardsError?) {
+                    override fun onWalletCardRetrievalError(error: GetWalletCardsError) {
                         Log.e(TAG, "Wallet card retrieval error, message: \"${error?.message}\"")
                         trySendWithFailureLogging(
                             KeyguardQuickAffordanceConfig.LockScreenState.Hidden,
@@ -133,13 +133,13 @@ constructor(
         return suspendCancellableCoroutine { continuation ->
             val callback =
                 object : QuickAccessWalletClient.OnWalletCardsRetrievedCallback {
-                    override fun onWalletCardsRetrieved(response: GetWalletCardsResponse?) {
+                    override fun onWalletCardsRetrieved(response: GetWalletCardsResponse) {
                         continuation.resumeWith(
                             Result.success(response?.walletCards ?: emptyList())
                         )
                     }
 
-                    override fun onWalletCardRetrievalError(error: GetWalletCardsError?) {
+                    override fun onWalletCardRetrievalError(error: GetWalletCardsError) {
                         continuation.resumeWith(Result.success(emptyList()))
                     }
                 }
diff --git a/packages/SystemUI/src/com/android/systemui/keyguard/data/repository/DeviceEntryFaceAuthRepository.kt b/packages/SystemUI/src/com/android/systemui/keyguard/data/repository/DeviceEntryFaceAuthRepository.kt
index 30f8f3edfa8fb..ff5094e276959 100644
--- a/packages/SystemUI/src/com/android/systemui/keyguard/data/repository/DeviceEntryFaceAuthRepository.kt
+++ b/packages/SystemUI/src/com/android/systemui/keyguard/data/repository/DeviceEntryFaceAuthRepository.kt
@@ -581,7 +581,7 @@ constructor(
             // We always want to invoke face detect in the main thread.
             faceAuthLogger.faceDetectionStarted()
             faceManager?.detectFace(
-                detectCancellationSignal,
+                checkNotNull(detectCancellationSignal),
                 detectionCallback,
                 FaceAuthenticateOptions.Builder().setUserId(currentUserId).build()
             )
diff --git a/packages/SystemUI/src/com/android/systemui/keyguard/data/repository/LightRevealScrimRepository.kt b/packages/SystemUI/src/com/android/systemui/keyguard/data/repository/LightRevealScrimRepository.kt
index 6a2511fdb90e0..1c0b73fcfa2d6 100644
--- a/packages/SystemUI/src/com/android/systemui/keyguard/data/repository/LightRevealScrimRepository.kt
+++ b/packages/SystemUI/src/com/android/systemui/keyguard/data/repository/LightRevealScrimRepository.kt
@@ -163,12 +163,13 @@ constructor(
 
     private fun constructCircleRevealFromPoint(point: Point): LightRevealEffect {
         return with(point) {
+            val display = checkNotNull(context.display)
             CircleReveal(
                 x,
                 y,
                 startRadius = 0,
                 endRadius =
-                    max(max(x, context.display.width - x), max(y, context.display.height - y)),
+                    max(max(x, display.width - x), max(y, display.height - y)),
             )
         }
     }
diff --git a/packages/SystemUI/src/com/android/systemui/keyguard/ui/binder/KeyguardBottomAreaViewBinder.kt b/packages/SystemUI/src/com/android/systemui/keyguard/ui/binder/KeyguardBottomAreaViewBinder.kt
index 0ead8c4a5b4f9..44acf4f0fd2d0 100644
--- a/packages/SystemUI/src/com/android/systemui/keyguard/ui/binder/KeyguardBottomAreaViewBinder.kt
+++ b/packages/SystemUI/src/com/android/systemui/keyguard/ui/binder/KeyguardBottomAreaViewBinder.kt
@@ -472,7 +472,7 @@ object KeyguardBottomAreaViewBinder {
             return true
         }
 
-        override fun onLongClickUseDefaultHapticFeedback(view: View?) = false
+        override fun onLongClickUseDefaultHapticFeedback(view: View) = false
     }
 
     @Deprecated("Deprecated as part of b/278057014")
diff --git a/packages/SystemUI/src/com/android/systemui/keyguard/ui/binder/KeyguardQuickAffordanceViewBinder.kt b/packages/SystemUI/src/com/android/systemui/keyguard/ui/binder/KeyguardQuickAffordanceViewBinder.kt
index 63a67913d6cd8..83b5463ea19c9 100644
--- a/packages/SystemUI/src/com/android/systemui/keyguard/ui/binder/KeyguardQuickAffordanceViewBinder.kt
+++ b/packages/SystemUI/src/com/android/systemui/keyguard/ui/binder/KeyguardQuickAffordanceViewBinder.kt
@@ -304,7 +304,7 @@ object KeyguardQuickAffordanceViewBinder {
             return true
         }
 
-        override fun onLongClickUseDefaultHapticFeedback(view: View?) = false
+        override fun onLongClickUseDefaultHapticFeedback(view: View) = false
 
     }
 
diff --git a/packages/SystemUI/src/com/android/systemui/keyguard/ui/binder/KeyguardSettingsViewBinder.kt b/packages/SystemUI/src/com/android/systemui/keyguard/ui/binder/KeyguardSettingsViewBinder.kt
index 162c109ee299b..82610e6ea59dd 100644
--- a/packages/SystemUI/src/com/android/systemui/keyguard/ui/binder/KeyguardSettingsViewBinder.kt
+++ b/packages/SystemUI/src/com/android/systemui/keyguard/ui/binder/KeyguardSettingsViewBinder.kt
@@ -43,7 +43,7 @@ object KeyguardSettingsViewBinder {
         vibratorHelper: VibratorHelper,
         activityStarter: ActivityStarter
     ): DisposableHandle {
-        val view = parentView.findViewById<LaunchableLinearLayout>(R.id.keyguard_settings_button)
+        val view = parentView.requireViewById<LaunchableLinearLayout>(R.id.keyguard_settings_button)
 
         val disposableHandle =
             view.repeatWhenAttached {
diff --git a/packages/SystemUI/src/com/android/systemui/keyguard/ui/binder/UdfpsKeyguardInternalViewBinder.kt b/packages/SystemUI/src/com/android/systemui/keyguard/ui/binder/UdfpsKeyguardInternalViewBinder.kt
index b568a9af9bb8f..3bb01f29aadf4 100644
--- a/packages/SystemUI/src/com/android/systemui/keyguard/ui/binder/UdfpsKeyguardInternalViewBinder.kt
+++ b/packages/SystemUI/src/com/android/systemui/keyguard/ui/binder/UdfpsKeyguardInternalViewBinder.kt
@@ -42,13 +42,13 @@ object UdfpsKeyguardInternalViewBinder {
         view.accessibilityDelegate = viewModel.accessibilityDelegate
 
         // bind child views
-        UdfpsAodFingerprintViewBinder.bind(view.findViewById(R.id.udfps_aod_fp), aodViewModel)
+        UdfpsAodFingerprintViewBinder.bind(view.requireViewById(R.id.udfps_aod_fp), aodViewModel)
         UdfpsFingerprintViewBinder.bind(
-            view.findViewById(R.id.udfps_lockscreen_fp),
+            view.requireViewById(R.id.udfps_lockscreen_fp),
             fingerprintViewModel
         )
         UdfpsBackgroundViewBinder.bind(
-            view.findViewById(R.id.udfps_keyguard_fp_bg),
+            view.requireViewById(R.id.udfps_keyguard_fp_bg),
             backgroundViewModel
         )
     }
diff --git a/packages/SystemUI/src/com/android/systemui/keyguard/ui/preview/KeyguardPreviewRenderer.kt b/packages/SystemUI/src/com/android/systemui/keyguard/ui/preview/KeyguardPreviewRenderer.kt
index 58bc552ad4ef5..580db3509997c 100644
--- a/packages/SystemUI/src/com/android/systemui/keyguard/ui/preview/KeyguardPreviewRenderer.kt
+++ b/packages/SystemUI/src/com/android/systemui/keyguard/ui/preview/KeyguardPreviewRenderer.kt
@@ -117,7 +117,7 @@ constructor(
     private var host: SurfaceControlViewHost
 
     val surfacePackage: SurfaceControlViewHost.SurfacePackage
-        get() = host.surfacePackage
+        get() = checkNotNull(host.surfacePackage)
 
     private lateinit var largeClockHostView: FrameLayout
     private lateinit var smallClockHostView: FrameLayout
diff --git a/packages/SystemUI/src/com/android/systemui/lifecycle/RepeatWhenAttached.kt b/packages/SystemUI/src/com/android/systemui/lifecycle/RepeatWhenAttached.kt
index e06483990c90b..5f7991e62cd76 100644
--- a/packages/SystemUI/src/com/android/systemui/lifecycle/RepeatWhenAttached.kt
+++ b/packages/SystemUI/src/com/android/systemui/lifecycle/RepeatWhenAttached.kt
@@ -70,7 +70,7 @@ fun View.repeatWhenAttached(
     var lifecycleOwner: ViewLifecycleOwner? = null
     val onAttachListener =
         object : View.OnAttachStateChangeListener {
-            override fun onViewAttachedToWindow(v: View?) {
+            override fun onViewAttachedToWindow(v: View) {
                 Assert.isMainThread()
                 lifecycleOwner?.onDestroy()
                 lifecycleOwner =
@@ -81,7 +81,7 @@ fun View.repeatWhenAttached(
                     )
             }
 
-            override fun onViewDetachedFromWindow(v: View?) {
+            override fun onViewDetachedFromWindow(v: View) {
                 lifecycleOwner?.onDestroy()
                 lifecycleOwner = null
             }
diff --git a/packages/SystemUI/src/com/android/systemui/media/controls/models/player/SeekBarViewModel.kt b/packages/SystemUI/src/com/android/systemui/media/controls/models/player/SeekBarViewModel.kt
index 35f5a8ca43456..a91917ab97c2c 100644
--- a/packages/SystemUI/src/com/android/systemui/media/controls/models/player/SeekBarViewModel.kt
+++ b/packages/SystemUI/src/com/android/systemui/media/controls/models/player/SeekBarViewModel.kt
@@ -514,7 +514,7 @@ constructor(
          * Returns true when the down event of the scroll hits within the target box of the thumb.
          */
         override fun onScroll(
-            eventStart: MotionEvent,
+            eventStart: MotionEvent?,
             event: MotionEvent,
             distanceX: Float,
             distanceY: Float
@@ -528,7 +528,7 @@ constructor(
          * Gestures that include a fling are considered a false gesture on the seek bar.
          */
         override fun onFling(
-            eventStart: MotionEvent,
+            eventStart: MotionEvent?,
             event: MotionEvent,
             velocityX: Float,
             velocityY: Float
diff --git a/packages/SystemUI/src/com/android/systemui/media/controls/pipeline/MediaDataFilter.kt b/packages/SystemUI/src/com/android/systemui/media/controls/pipeline/MediaDataFilter.kt
index 207df6bc44222..a1291a4d6b0f4 100644
--- a/packages/SystemUI/src/com/android/systemui/media/controls/pipeline/MediaDataFilter.kt
+++ b/packages/SystemUI/src/com/android/systemui/media/controls/pipeline/MediaDataFilter.kt
@@ -149,11 +149,7 @@ constructor(
         // Check if smartspace has explicitly specified whether to re-activate resumable media.
         // The default behavior is to trigger if the smartspace data is active.
         val shouldTriggerResume =
-            if (data.cardAction?.extras?.containsKey(EXTRA_KEY_TRIGGER_RESUME) == true) {
-                data.cardAction.extras.getBoolean(EXTRA_KEY_TRIGGER_RESUME, true)
-            } else {
-                true
-            }
+            data.cardAction?.extras?.getBoolean(EXTRA_KEY_TRIGGER_RESUME, true) ?: true
         val shouldReactivate =
             shouldTriggerResume && !hasActiveMedia() && hasAnyMedia() && data.isActive
 
@@ -269,9 +265,7 @@ constructor(
                     "Cannot create dismiss action click action: extras missing dismiss_intent."
                 )
             } else if (
-                dismissIntent.getComponent() != null &&
-                    dismissIntent.getComponent().getClassName() ==
-                        EXPORTED_SMARTSPACE_TRAMPOLINE_ACTIVITY_NAME
+                dismissIntent.component?.className == EXPORTED_SMARTSPACE_TRAMPOLINE_ACTIVITY_NAME
             ) {
                 // Dismiss the card Smartspace data through Smartspace trampoline activity.
                 context.startActivity(dismissIntent)
diff --git a/packages/SystemUI/src/com/android/systemui/media/controls/pipeline/MediaDataManager.kt b/packages/SystemUI/src/com/android/systemui/media/controls/pipeline/MediaDataManager.kt
index 576eb9e6cb079..282a65af14247 100644
--- a/packages/SystemUI/src/com/android/systemui/media/controls/pipeline/MediaDataManager.kt
+++ b/packages/SystemUI/src/com/android/systemui/media/controls/pipeline/MediaDataManager.kt
@@ -22,6 +22,7 @@ import android.app.Notification
 import android.app.Notification.EXTRA_SUBSTITUTE_APP_NAME
 import android.app.PendingIntent
 import android.app.StatusBarManager
+import android.app.smartspace.SmartspaceAction
 import android.app.smartspace.SmartspaceConfig
 import android.app.smartspace.SmartspaceManager
 import android.app.smartspace.SmartspaceSession
@@ -1623,20 +1624,18 @@ class MediaDataManager(
      *   SmartspaceTarget's data is invalid.
      */
     private fun toSmartspaceMediaData(target: SmartspaceTarget): SmartspaceMediaData {
-        var dismissIntent: Intent? = null
-        if (target.baseAction != null && target.baseAction.extras != null) {
-            dismissIntent =
-                target.baseAction.extras.getParcelable(EXTRAS_SMARTSPACE_DISMISS_INTENT_KEY)
-                    as Intent?
-        }
+        val baseAction: SmartspaceAction? = target.baseAction
+        val dismissIntent =
+            baseAction?.extras?.getParcelable(EXTRAS_SMARTSPACE_DISMISS_INTENT_KEY) as Intent?
 
         val isActive =
             when {
                 !mediaFlags.isPersistentSsCardEnabled() -> true
-                target.baseAction == null -> true
-                else ->
-                    target.baseAction.extras.getString(EXTRA_KEY_TRIGGER_SOURCE) !=
-                        EXTRA_VALUE_TRIGGER_PERIODIC
+                baseAction == null -> true
+                else -> {
+                    val triggerSource = baseAction.extras?.getString(EXTRA_KEY_TRIGGER_SOURCE)
+                    triggerSource != EXTRA_VALUE_TRIGGER_PERIODIC
+                }
             }
 
         packageName(target)?.let {
diff --git a/packages/SystemUI/src/com/android/systemui/media/controls/pipeline/MediaSessionBasedFilter.kt b/packages/SystemUI/src/com/android/systemui/media/controls/pipeline/MediaSessionBasedFilter.kt
index d6f941de1b6d4..6a8ffb7d8c424 100644
--- a/packages/SystemUI/src/com/android/systemui/media/controls/pipeline/MediaSessionBasedFilter.kt
+++ b/packages/SystemUI/src/com/android/systemui/media/controls/pipeline/MediaSessionBasedFilter.kt
@@ -65,7 +65,7 @@ constructor(
 
     private val sessionListener =
         object : MediaSessionManager.OnActiveSessionsChangedListener {
-            override fun onActiveSessionsChanged(controllers: List<MediaController>) {
+            override fun onActiveSessionsChanged(controllers: List<MediaController>?) {
                 handleControllersChanged(controllers)
             }
         }
@@ -190,16 +190,18 @@ constructor(
         }
     }
 
-    private fun handleControllersChanged(controllers: List<MediaController>) {
+    private fun handleControllersChanged(controllers: List<MediaController>?) {
         packageControllers.clear()
-        controllers.forEach { controller ->
+        controllers?.forEach { controller ->
             packageControllers.get(controller.packageName)?.let { tokens -> tokens.add(controller) }
                 ?: run {
                     val tokens = mutableListOf(controller)
                     packageControllers.put(controller.packageName, tokens)
                 }
         }
-        tokensWithNotifications.retainAll(controllers.map { TokenId(it.sessionToken) })
+        controllers?.map { TokenId(it.sessionToken) }?.let {
+            tokensWithNotifications.retainAll(it)
+        }
     }
 
     /**
diff --git a/packages/SystemUI/src/com/android/systemui/media/controls/ui/IlluminationDrawable.kt b/packages/SystemUI/src/com/android/systemui/media/controls/ui/IlluminationDrawable.kt
index b46ebb22ff057..b9cc772e7136f 100644
--- a/packages/SystemUI/src/com/android/systemui/media/controls/ui/IlluminationDrawable.kt
+++ b/packages/SystemUI/src/com/android/systemui/media/controls/ui/IlluminationDrawable.kt
@@ -195,7 +195,7 @@ class IlluminationDrawable : Drawable() {
                 }
                 addListener(
                     object : AnimatorListenerAdapter() {
-                        override fun onAnimationEnd(animation: Animator?) {
+                        override fun onAnimationEnd(animation: Animator) {
                             backgroundAnimation = null
                         }
                     }
diff --git a/packages/SystemUI/src/com/android/systemui/media/controls/ui/LightSourceDrawable.kt b/packages/SystemUI/src/com/android/systemui/media/controls/ui/LightSourceDrawable.kt
index 937a618df68f9..646d1d0ff0fca 100644
--- a/packages/SystemUI/src/com/android/systemui/media/controls/ui/LightSourceDrawable.kt
+++ b/packages/SystemUI/src/com/android/systemui/media/controls/ui/LightSourceDrawable.kt
@@ -98,11 +98,11 @@ class LightSourceDrawable : Drawable() {
                         addListener(
                             object : AnimatorListenerAdapter() {
                                 var cancelled = false
-                                override fun onAnimationCancel(animation: Animator?) {
+                                override fun onAnimationCancel(animation: Animator) {
                                     cancelled = true
                                 }
 
-                                override fun onAnimationEnd(animation: Animator?) {
+                                override fun onAnimationEnd(animation: Animator) {
                                     if (cancelled) {
                                         return
                                     }
@@ -226,7 +226,7 @@ class LightSourceDrawable : Drawable() {
                 )
                 addListener(
                     object : AnimatorListenerAdapter() {
-                        override fun onAnimationEnd(animation: Animator?) {
+                        override fun onAnimationEnd(animation: Animator) {
                             rippleData.progress = 0f
                             rippleAnimation = null
                             invalidateSelf()
@@ -270,11 +270,8 @@ class LightSourceDrawable : Drawable() {
         return bounds
     }
 
-    override fun onStateChange(stateSet: IntArray?): Boolean {
+    override fun onStateChange(stateSet: IntArray): Boolean {
         val changed = super.onStateChange(stateSet)
-        if (stateSet == null) {
-            return changed
-        }
 
         val wasPressed = pressed
         var enabled = false
diff --git a/packages/SystemUI/src/com/android/systemui/media/controls/ui/MediaCarouselScrollHandler.kt b/packages/SystemUI/src/com/android/systemui/media/controls/ui/MediaCarouselScrollHandler.kt
index 1ace3168780a4..ce50a11cd85d7 100644
--- a/packages/SystemUI/src/com/android/systemui/media/controls/ui/MediaCarouselScrollHandler.kt
+++ b/packages/SystemUI/src/com/android/systemui/media/controls/ui/MediaCarouselScrollHandler.kt
@@ -127,19 +127,19 @@ class MediaCarouselScrollHandler(
         object : GestureDetector.SimpleOnGestureListener() {
             override fun onFling(
                 eStart: MotionEvent?,
-                eCurrent: MotionEvent?,
+                eCurrent: MotionEvent,
                 vX: Float,
                 vY: Float
             ) = onFling(vX, vY)
 
             override fun onScroll(
                 down: MotionEvent?,
-                lastMotion: MotionEvent?,
+                lastMotion: MotionEvent,
                 distanceX: Float,
                 distanceY: Float
-            ) = onScroll(down!!, lastMotion!!, distanceX)
+            ) = onScroll(down!!, lastMotion, distanceX)
 
-            override fun onDown(e: MotionEvent?): Boolean {
+            override fun onDown(e: MotionEvent): Boolean {
                 if (falsingProtectionNeeded) {
                     falsingCollector.onNotificationStartDismissing()
                 }
diff --git a/packages/SystemUI/src/com/android/systemui/media/controls/ui/MediaHierarchyManager.kt b/packages/SystemUI/src/com/android/systemui/media/controls/ui/MediaHierarchyManager.kt
index fe8ebafdf9b4c..c1c757e424dc0 100644
--- a/packages/SystemUI/src/com/android/systemui/media/controls/ui/MediaHierarchyManager.kt
+++ b/packages/SystemUI/src/com/android/systemui/media/controls/ui/MediaHierarchyManager.kt
@@ -180,20 +180,20 @@ constructor(
                 object : AnimatorListenerAdapter() {
                     private var cancelled: Boolean = false
 
-                    override fun onAnimationCancel(animation: Animator?) {
+                    override fun onAnimationCancel(animation: Animator) {
                         cancelled = true
                         animationPending = false
                         rootView?.removeCallbacks(startAnimation)
                     }
 
-                    override fun onAnimationEnd(animation: Animator?) {
+                    override fun onAnimationEnd(animation: Animator) {
                         isCrossFadeAnimatorRunning = false
                         if (!cancelled) {
                             applyTargetStateIfNotAnimating()
                         }
                     }
 
-                    override fun onAnimationStart(animation: Animator?) {
+                    override fun onAnimationStart(animation: Animator) {
                         cancelled = false
                         animationPending = false
                     }
@@ -606,7 +606,7 @@ constructor(
         val viewHost = UniqueObjectHostView(context)
         viewHost.addOnAttachStateChangeListener(
             object : View.OnAttachStateChangeListener {
-                override fun onViewAttachedToWindow(p0: View?) {
+                override fun onViewAttachedToWindow(p0: View) {
                     if (rootOverlay == null) {
                         rootView = viewHost.viewRootImpl.view
                         rootOverlay = (rootView!!.overlay as ViewGroupOverlay)
@@ -614,7 +614,7 @@ constructor(
                     viewHost.removeOnAttachStateChangeListener(this)
                 }
 
-                override fun onViewDetachedFromWindow(p0: View?) {}
+                override fun onViewDetachedFromWindow(p0: View) {}
             }
         )
         return viewHost
diff --git a/packages/SystemUI/src/com/android/systemui/media/controls/ui/MediaHost.kt b/packages/SystemUI/src/com/android/systemui/media/controls/ui/MediaHost.kt
index be570b4a11198..631a0b8471b86 100644
--- a/packages/SystemUI/src/com/android/systemui/media/controls/ui/MediaHost.kt
+++ b/packages/SystemUI/src/com/android/systemui/media/controls/ui/MediaHost.kt
@@ -144,12 +144,12 @@ constructor(
         setListeningToMediaData(true)
         hostView.addOnAttachStateChangeListener(
             object : OnAttachStateChangeListener {
-                override fun onViewAttachedToWindow(v: View?) {
+                override fun onViewAttachedToWindow(v: View) {
                     setListeningToMediaData(true)
                     updateViewVisibility()
                 }
 
-                override fun onViewDetachedFromWindow(v: View?) {
+                override fun onViewDetachedFromWindow(v: View) {
                     setListeningToMediaData(false)
                 }
             }
diff --git a/packages/SystemUI/src/com/android/systemui/media/controls/ui/SquigglyProgress.kt b/packages/SystemUI/src/com/android/systemui/media/controls/ui/SquigglyProgress.kt
index 583c626d21563..16dfc21304020 100644
--- a/packages/SystemUI/src/com/android/systemui/media/controls/ui/SquigglyProgress.kt
+++ b/packages/SystemUI/src/com/android/systemui/media/controls/ui/SquigglyProgress.kt
@@ -117,7 +117,7 @@ class SquigglyProgress : Drawable() {
                     }
                     addListener(
                         object : AnimatorListenerAdapter() {
-                            override fun onAnimationEnd(animation: Animator?) {
+                            override fun onAnimationEnd(animation: Animator) {
                                 heightAnimator = null
                             }
                         }
diff --git a/packages/SystemUI/src/com/android/systemui/media/taptotransfer/receiver/MediaTttChipControllerReceiver.kt b/packages/SystemUI/src/com/android/systemui/media/taptotransfer/receiver/MediaTttChipControllerReceiver.kt
index bbd3d33e45c8e..da8e106d3019d 100644
--- a/packages/SystemUI/src/com/android/systemui/media/taptotransfer/receiver/MediaTttChipControllerReceiver.kt
+++ b/packages/SystemUI/src/com/android/systemui/media/taptotransfer/receiver/MediaTttChipControllerReceiver.kt
@@ -201,13 +201,13 @@ open class MediaTttChipControllerReceiver @Inject constructor(
     }
 
     override fun updateView(newInfo: ChipReceiverInfo, currentView: ViewGroup) {
-        val packageName = newInfo.routeInfo.clientPackageName
+        val packageName: String? = newInfo.routeInfo.clientPackageName
         var iconInfo = MediaTttUtils.getIconInfoFromPackageName(
             context,
             packageName,
             isReceiver = true,
         ) {
-            logger.logPackageNotFound(packageName)
+            packageName?.let { logger.logPackageNotFound(it) }
         }
 
         if (newInfo.appNameOverride != null) {
diff --git a/packages/SystemUI/src/com/android/systemui/media/taptotransfer/receiver/MediaTttReceiverRippleController.kt b/packages/SystemUI/src/com/android/systemui/media/taptotransfer/receiver/MediaTttReceiverRippleController.kt
index 50138024e2685..fbf7e25981dad 100644
--- a/packages/SystemUI/src/com/android/systemui/media/taptotransfer/receiver/MediaTttReceiverRippleController.kt
+++ b/packages/SystemUI/src/com/android/systemui/media/taptotransfer/receiver/MediaTttReceiverRippleController.kt
@@ -68,9 +68,9 @@ constructor(
         )
         rippleView.addOnAttachStateChangeListener(
             object : View.OnAttachStateChangeListener {
-                override fun onViewDetachedFromWindow(view: View?) {}
+                override fun onViewDetachedFromWindow(view: View) {}
 
-                override fun onViewAttachedToWindow(view: View?) {
+                override fun onViewAttachedToWindow(view: View) {
                     if (view == null) {
                         return
                     }
diff --git a/packages/SystemUI/src/com/android/systemui/media/taptotransfer/receiver/ReceiverChipRippleView.kt b/packages/SystemUI/src/com/android/systemui/media/taptotransfer/receiver/ReceiverChipRippleView.kt
index 0b0535df6228c..35018f1903949 100644
--- a/packages/SystemUI/src/com/android/systemui/media/taptotransfer/receiver/ReceiverChipRippleView.kt
+++ b/packages/SystemUI/src/com/android/systemui/media/taptotransfer/receiver/ReceiverChipRippleView.kt
@@ -54,7 +54,7 @@ class ReceiverChipRippleView(context: Context?, attrs: AttributeSet?) : RippleVi
         // Reset all listeners to animator.
         animator.removeAllListeners()
         animator.addListener(object : AnimatorListenerAdapter() {
-            override fun onAnimationEnd(animation: Animator?) {
+            override fun onAnimationEnd(animation: Animator) {
                 onAnimationEnd?.run()
                 isStarted = false
             }
@@ -86,7 +86,7 @@ class ReceiverChipRippleView(context: Context?, attrs: AttributeSet?) : RippleVi
             invalidate()
         }
         animator.addListener(object : AnimatorListenerAdapter() {
-            override fun onAnimationEnd(animation: Animator?) {
+            override fun onAnimationEnd(animation: Animator) {
                 animation?.let { visibility = GONE }
                 onAnimationEnd?.run()
                 isStarted = false
diff --git a/packages/SystemUI/src/com/android/systemui/media/taptotransfer/sender/MediaTttSenderCoordinator.kt b/packages/SystemUI/src/com/android/systemui/media/taptotransfer/sender/MediaTttSenderCoordinator.kt
index f75f8b9a18f75..87d0098805b36 100644
--- a/packages/SystemUI/src/com/android/systemui/media/taptotransfer/sender/MediaTttSenderCoordinator.kt
+++ b/packages/SystemUI/src/com/android/systemui/media/taptotransfer/sender/MediaTttSenderCoordinator.kt
@@ -162,7 +162,7 @@ constructor(
         logger: MediaTttSenderLogger,
         instanceId: InstanceId,
     ): ChipbarInfo {
-        val packageName = routeInfo.clientPackageName
+        val packageName = checkNotNull(routeInfo.clientPackageName)
         val otherDeviceName =
             if (routeInfo.name.isBlank()) {
                 context.getString(R.string.media_ttt_default_device_type)
diff --git a/packages/SystemUI/src/com/android/systemui/mediaprojection/appselector/view/MediaProjectionRecentsViewController.kt b/packages/SystemUI/src/com/android/systemui/mediaprojection/appselector/view/MediaProjectionRecentsViewController.kt
index c816446d5c25d..64de9bd76122a 100644
--- a/packages/SystemUI/src/com/android/systemui/mediaprojection/appselector/view/MediaProjectionRecentsViewController.kt
+++ b/packages/SystemUI/src/com/android/systemui/mediaprojection/appselector/view/MediaProjectionRecentsViewController.kt
@@ -88,7 +88,7 @@ constructor(
                 .inflate(R.layout.media_projection_recent_tasks, parent, /* attachToRoot= */ false)
                 as ViewGroup
 
-        val container = recentsRoot.findViewById<View>(R.id.media_projection_recent_tasks_container)
+        val container = recentsRoot.requireViewById<View>(R.id.media_projection_recent_tasks_container)
         container.setTaskHeightSize()
 
         val progress = recentsRoot.requireViewById<View>(R.id.media_projection_recent_tasks_loader)
diff --git a/packages/SystemUI/src/com/android/systemui/mediaprojection/taskswitcher/data/repository/MediaProjectionManagerRepository.kt b/packages/SystemUI/src/com/android/systemui/mediaprojection/taskswitcher/data/repository/MediaProjectionManagerRepository.kt
index 38d4e698f2d93..6480a47e8ea23 100644
--- a/packages/SystemUI/src/com/android/systemui/mediaprojection/taskswitcher/data/repository/MediaProjectionManagerRepository.kt
+++ b/packages/SystemUI/src/com/android/systemui/mediaprojection/taskswitcher/data/repository/MediaProjectionManagerRepository.kt
@@ -81,8 +81,8 @@ constructor(
             return MediaProjectionState.EntireScreen
         }
         val matchingTask =
-            tasksRepository.findRunningTaskFromWindowContainerToken(session.tokenToRecord)
-                ?: return MediaProjectionState.EntireScreen
+            tasksRepository.findRunningTaskFromWindowContainerToken(
+                checkNotNull(session.tokenToRecord)) ?: return MediaProjectionState.EntireScreen
         return MediaProjectionState.SingleTask(matchingTask)
     }
 
diff --git a/packages/SystemUI/src/com/android/systemui/notetask/NoteTaskRoleManagerExt.kt b/packages/SystemUI/src/com/android/systemui/notetask/NoteTaskRoleManagerExt.kt
index 4d30634cda385..63d4634026556 100644
--- a/packages/SystemUI/src/com/android/systemui/notetask/NoteTaskRoleManagerExt.kt
+++ b/packages/SystemUI/src/com/android/systemui/notetask/NoteTaskRoleManagerExt.kt
@@ -77,8 +77,13 @@ internal object NoteTaskRoleManagerExt {
             .build()
     }
 
-    private fun PackageManager.getApplicationLabel(packageName: String?): String? =
-        runCatching { getApplicationInfo(packageName, /* flags= */ 0)!! }
+    private fun PackageManager.getApplicationLabel(packageName: String?): String? {
+        if (packageName == null) {
+            return null
+        }
+
+        return runCatching { getApplicationInfo(packageName, /* flags= */ 0)!! }
             .getOrNull()
             ?.let { info -> getApplicationLabel(info).toString() }
+    }
 }
diff --git a/packages/SystemUI/src/com/android/systemui/people/ui/view/PeopleViewBinder.kt b/packages/SystemUI/src/com/android/systemui/people/ui/view/PeopleViewBinder.kt
index 5f338c30c9666..46c8d358aaac8 100644
--- a/packages/SystemUI/src/com/android/systemui/people/ui/view/PeopleViewBinder.kt
+++ b/packages/SystemUI/src/com/android/systemui/people/ui/view/PeopleViewBinder.kt
@@ -132,13 +132,13 @@ object PeopleViewBinder {
             LayoutInflater.from(context)
                 .inflate(R.layout.people_space_activity_no_conversations, /* root= */ view)
 
-        noConversationsView.findViewById<View>(R.id.got_it_button).setOnClickListener {
+        noConversationsView.requireViewById<View>(R.id.got_it_button).setOnClickListener {
             onGotItClicked()
         }
 
         // The Tile preview has colorBackground as its background. Change it so it's different than
         // the activity's background.
-        val item = noConversationsView.findViewById<LinearLayout>(android.R.id.background)
+        val item = noConversationsView.requireViewById<LinearLayout>(android.R.id.background)
         val shape = item.background as GradientDrawable
         val ta =
             context.theme.obtainStyledAttributes(
diff --git a/packages/SystemUI/src/com/android/systemui/privacy/PrivacyDialogV2.kt b/packages/SystemUI/src/com/android/systemui/privacy/PrivacyDialogV2.kt
index f4aa27d5fcbba..c202f14edc4d2 100644
--- a/packages/SystemUI/src/com/android/systemui/privacy/PrivacyDialogV2.kt
+++ b/packages/SystemUI/src/com/android/systemui/privacy/PrivacyDialogV2.kt
@@ -192,7 +192,7 @@ class PrivacyDialogV2(
             return null
         }
         val closeAppButton =
-            window.layoutInflater.inflate(
+            checkNotNull(window).layoutInflater.inflate(
                 R.layout.privacy_dialog_card_button,
                 expandedLayout,
                 false
@@ -248,7 +248,7 @@ class PrivacyDialogV2(
 
     private fun configureManageButton(element: PrivacyElement, expandedLayout: ViewGroup): View {
         val manageButton =
-            window.layoutInflater.inflate(
+            checkNotNull(window).layoutInflater.inflate(
                 R.layout.privacy_dialog_card_button,
                 expandedLayout,
                 false
diff --git a/packages/SystemUI/src/com/android/systemui/screenrecord/BaseScreenSharePermissionDialog.kt b/packages/SystemUI/src/com/android/systemui/screenrecord/BaseScreenSharePermissionDialog.kt
index b34004397520f..23894a3f78356 100644
--- a/packages/SystemUI/src/com/android/systemui/screenrecord/BaseScreenSharePermissionDialog.kt
+++ b/packages/SystemUI/src/com/android/systemui/screenrecord/BaseScreenSharePermissionDialog.kt
@@ -50,22 +50,20 @@ open class BaseScreenSharePermissionDialog(
 
     public override fun onCreate(savedInstanceState: Bundle?) {
         super.onCreate(savedInstanceState)
-        window.apply {
-            addPrivateFlags(WindowManager.LayoutParams.SYSTEM_FLAG_SHOW_FOR_ALL_USERS)
-            setGravity(Gravity.CENTER)
-        }
+        window?.addPrivateFlags(WindowManager.LayoutParams.SYSTEM_FLAG_SHOW_FOR_ALL_USERS)
+        window?.setGravity(Gravity.CENTER)
         setContentView(R.layout.screen_share_dialog)
-        dialogTitle = findViewById(R.id.screen_share_dialog_title)
-        warning = findViewById(R.id.text_warning)
-        startButton = findViewById(android.R.id.button1)
-        cancelButton = findViewById(android.R.id.button2)
+        dialogTitle = requireViewById(R.id.screen_share_dialog_title)
+        warning = requireViewById(R.id.text_warning)
+        startButton = requireViewById(android.R.id.button1)
+        cancelButton = requireViewById(android.R.id.button2)
         updateIcon()
         initScreenShareOptions()
         createOptionsView(getOptionsViewLayoutId())
     }
 
     private fun updateIcon() {
-        val icon = findViewById<ImageView>(R.id.screen_share_dialog_icon)
+        val icon = requireViewById<ImageView>(R.id.screen_share_dialog_icon)
         if (dialogIconTint != null) {
             icon.setColorFilter(context.getColor(dialogIconTint))
         }
@@ -92,7 +90,7 @@ open class BaseScreenSharePermissionDialog(
                 options
             )
         adapter.setDropDownViewResource(R.layout.screen_share_dialog_spinner_item_text)
-        screenShareModeSpinner = findViewById(R.id.screen_share_mode_spinner)
+        screenShareModeSpinner = requireViewById(R.id.screen_share_mode_spinner)
         screenShareModeSpinner.adapter = adapter
         screenShareModeSpinner.onItemSelectedListener = this
     }
diff --git a/packages/SystemUI/src/com/android/systemui/screenrecord/ScreenRecordPermissionDialog.kt b/packages/SystemUI/src/com/android/systemui/screenrecord/ScreenRecordPermissionDialog.kt
index 604d44967e68e..e8683fbea7359 100644
--- a/packages/SystemUI/src/com/android/systemui/screenrecord/ScreenRecordPermissionDialog.kt
+++ b/packages/SystemUI/src/com/android/systemui/screenrecord/ScreenRecordPermissionDialog.kt
@@ -100,11 +100,11 @@ class ScreenRecordPermissionDialog(
     @LayoutRes override fun getOptionsViewLayoutId(): Int = R.layout.screen_record_options
 
     private fun initRecordOptionsView() {
-        audioSwitch = findViewById(R.id.screenrecord_audio_switch)
-        tapsSwitch = findViewById(R.id.screenrecord_taps_switch)
-        tapsView = findViewById(R.id.show_taps)
+        audioSwitch = requireViewById(R.id.screenrecord_audio_switch)
+        tapsSwitch = requireViewById(R.id.screenrecord_taps_switch)
+        tapsView = requireViewById(R.id.show_taps)
         updateTapsViewVisibility()
-        options = findViewById(R.id.screen_recording_options)
+        options = requireViewById(R.id.screen_recording_options)
         val a: ArrayAdapter<*> =
             ScreenRecordingAdapter(context, android.R.layout.simple_spinner_dropdown_item, MODES)
         a.setDropDownViewResource(android.R.layout.simple_spinner_dropdown_item)
diff --git a/packages/SystemUI/src/com/android/systemui/shade/ShadeHeaderController.kt b/packages/SystemUI/src/com/android/systemui/shade/ShadeHeaderController.kt
index c6cb9c4d347c4..bea12de5ab495 100644
--- a/packages/SystemUI/src/com/android/systemui/shade/ShadeHeaderController.kt
+++ b/packages/SystemUI/src/com/android/systemui/shade/ShadeHeaderController.kt
@@ -130,12 +130,12 @@ constructor(
     private lateinit var carrierIconSlots: List<String>
     private lateinit var mShadeCarrierGroupController: ShadeCarrierGroupController
 
-    private val batteryIcon: BatteryMeterView = header.findViewById(R.id.batteryRemainingIcon)
-    private val clock: Clock = header.findViewById(R.id.clock)
-    private val date: TextView = header.findViewById(R.id.date)
-    private val iconContainer: StatusIconContainer = header.findViewById(R.id.statusIcons)
-    private val mShadeCarrierGroup: ShadeCarrierGroup = header.findViewById(R.id.carrier_group)
-    private val systemIcons: View = header.findViewById(R.id.shade_header_system_icons)
+    private val batteryIcon: BatteryMeterView = header.requireViewById(R.id.batteryRemainingIcon)
+    private val clock: Clock = header.requireViewById(R.id.clock)
+    private val date: TextView = header.requireViewById(R.id.date)
+    private val iconContainer: StatusIconContainer = header.requireViewById(R.id.statusIcons)
+    private val mShadeCarrierGroup: ShadeCarrierGroup = header.requireViewById(R.id.carrier_group)
+    private val systemIcons: View = header.requireViewById(R.id.shade_header_system_icons)
 
     private var roundedCorners = 0
     private var cutout: DisplayCutout? = null
@@ -582,7 +582,7 @@ constructor(
     inner class CustomizerAnimationListener(
         private val enteringCustomizing: Boolean,
     ) : AnimatorListenerAdapter() {
-        override fun onAnimationEnd(animation: Animator?) {
+        override fun onAnimationEnd(animation: Animator) {
             super.onAnimationEnd(animation)
             header.animate().setListener(null)
             if (enteringCustomizing) {
@@ -590,7 +590,7 @@ constructor(
             }
         }
 
-        override fun onAnimationStart(animation: Animator?) {
+        override fun onAnimationStart(animation: Animator) {
             super.onAnimationStart(animation)
             if (!enteringCustomizing) {
                 customizing = false
diff --git a/packages/SystemUI/src/com/android/systemui/shade/ShadeViewProviderModule.kt b/packages/SystemUI/src/com/android/systemui/shade/ShadeViewProviderModule.kt
index 6e7678407805b..05b1ac64a5f65 100644
--- a/packages/SystemUI/src/com/android/systemui/shade/ShadeViewProviderModule.kt
+++ b/packages/SystemUI/src/com/android/systemui/shade/ShadeViewProviderModule.kt
@@ -106,7 +106,7 @@ abstract class ShadeViewProviderModule {
             featureFlags: FeatureFlags,
         ): NotificationShadeWindowView {
             if (featureFlags.isEnabled(Flags.SCENE_CONTAINER)) {
-                return root.findViewById(R.id.legacy_window_root)
+                return root.requireViewById(R.id.legacy_window_root)
             }
             return root as NotificationShadeWindowView?
                 ?: throw IllegalStateException("root view not a NotificationShadeWindowView")
@@ -118,7 +118,7 @@ abstract class ShadeViewProviderModule {
         fun providesNotificationStackScrollLayout(
             notificationShadeWindowView: NotificationShadeWindowView,
         ): NotificationStackScrollLayout {
-            return notificationShadeWindowView.findViewById(R.id.notification_stack_scroller)
+            return notificationShadeWindowView.requireViewById(R.id.notification_stack_scroller)
         }
 
         @Provides
@@ -153,7 +153,7 @@ abstract class ShadeViewProviderModule {
         fun providesNotificationPanelView(
             notificationShadeWindowView: NotificationShadeWindowView,
         ): NotificationPanelView {
-            return notificationShadeWindowView.findViewById(R.id.notification_panel)
+            return notificationShadeWindowView.requireViewById(R.id.notification_panel)
         }
 
         /**
@@ -175,7 +175,7 @@ abstract class ShadeViewProviderModule {
         fun providesLightRevealScrim(
             notificationShadeWindowView: NotificationShadeWindowView,
         ): LightRevealScrim {
-            return notificationShadeWindowView.findViewById(R.id.light_reveal_scrim)
+            return notificationShadeWindowView.requireViewById(R.id.light_reveal_scrim)
         }
 
         @Provides
@@ -183,7 +183,7 @@ abstract class ShadeViewProviderModule {
         fun providesKeyguardRootView(
             notificationShadeWindowView: NotificationShadeWindowView,
         ): KeyguardRootView {
-            return notificationShadeWindowView.findViewById(R.id.keyguard_root_view)
+            return notificationShadeWindowView.requireViewById(R.id.keyguard_root_view)
         }
 
         @Provides
@@ -191,7 +191,7 @@ abstract class ShadeViewProviderModule {
         fun providesSharedNotificationContainer(
             notificationShadeWindowView: NotificationShadeWindowView,
         ): SharedNotificationContainer {
-            return notificationShadeWindowView.findViewById(R.id.shared_notification_container)
+            return notificationShadeWindowView.requireViewById(R.id.shared_notification_container)
         }
 
         // TODO(b/277762009): Only allow this view's controller to inject the view. See above.
@@ -200,7 +200,7 @@ abstract class ShadeViewProviderModule {
         fun providesAuthRippleView(
             notificationShadeWindowView: NotificationShadeWindowView,
         ): AuthRippleView? {
-            return notificationShadeWindowView.findViewById(R.id.auth_ripple)
+            return notificationShadeWindowView.requireViewById(R.id.auth_ripple)
         }
 
         // TODO(b/277762009): Only allow this view's controller to inject the view. See above.
@@ -212,9 +212,9 @@ abstract class ShadeViewProviderModule {
             featureFlags: FeatureFlags
         ): LockIconView {
             if (featureFlags.isEnabled(Flags.MIGRATE_LOCK_ICON)) {
-                return keyguardRootView.findViewById(R.id.lock_icon_view)
+                return keyguardRootView.requireViewById(R.id.lock_icon_view)
             } else {
-                return notificationPanelView.findViewById(R.id.lock_icon_view)
+                return notificationPanelView.requireViewById(R.id.lock_icon_view)
             }
         }
 
@@ -224,7 +224,7 @@ abstract class ShadeViewProviderModule {
         fun providesTapAgainView(
             notificationPanelView: NotificationPanelView,
         ): TapAgainView {
-            return notificationPanelView.findViewById(R.id.shade_falsing_tap_again)
+            return notificationPanelView.requireViewById(R.id.shade_falsing_tap_again)
         }
 
         // TODO(b/277762009): Only allow this view's controller to inject the view. See above.
@@ -233,7 +233,7 @@ abstract class ShadeViewProviderModule {
         fun providesNotificationsQuickSettingsContainer(
             notificationShadeWindowView: NotificationShadeWindowView,
         ): NotificationsQuickSettingsContainer {
-            return notificationShadeWindowView.findViewById(R.id.notification_container_parent)
+            return notificationShadeWindowView.requireViewById(R.id.notification_container_parent)
         }
 
         // TODO(b/277762009): Only allow this view's controller to inject the view. See above.
@@ -243,7 +243,7 @@ abstract class ShadeViewProviderModule {
         fun providesShadeHeaderView(
             notificationShadeWindowView: NotificationShadeWindowView,
         ): MotionLayout {
-            val stub = notificationShadeWindowView.findViewById<ViewStub>(R.id.qs_header_stub)
+            val stub = notificationShadeWindowView.requireViewById<ViewStub>(R.id.qs_header_stub)
             val layoutId = R.layout.combined_qs_header
             stub.layoutResource = layoutId
             return stub.inflate() as MotionLayout
@@ -260,7 +260,7 @@ abstract class ShadeViewProviderModule {
         @SysUISingleton
         @Named(SHADE_HEADER)
         fun providesBatteryMeterView(@Named(SHADE_HEADER) view: MotionLayout): BatteryMeterView {
-            return view.findViewById(R.id.batteryRemainingIcon)
+            return view.requireViewById(R.id.batteryRemainingIcon)
         }
 
         @Provides
@@ -295,7 +295,7 @@ abstract class ShadeViewProviderModule {
         fun providesOngoingPrivacyChip(
             @Named(SHADE_HEADER) header: MotionLayout,
         ): OngoingPrivacyChip {
-            return header.findViewById(R.id.privacy_chip)
+            return header.requireViewById(R.id.privacy_chip)
         }
 
         @Provides
@@ -304,7 +304,7 @@ abstract class ShadeViewProviderModule {
         fun providesStatusIconContainer(
             @Named(SHADE_HEADER) header: MotionLayout,
         ): StatusIconContainer {
-            return header.findViewById(R.id.statusIcons)
+            return header.requireViewById(R.id.statusIcons)
         }
     }
 }
diff --git a/packages/SystemUI/src/com/android/systemui/statusbar/BatteryStatusChip.kt b/packages/SystemUI/src/com/android/systemui/statusbar/BatteryStatusChip.kt
index 37140ec2aa323..520976746785e 100644
--- a/packages/SystemUI/src/com/android/systemui/statusbar/BatteryStatusChip.kt
+++ b/packages/SystemUI/src/com/android/systemui/statusbar/BatteryStatusChip.kt
@@ -37,8 +37,8 @@ class BatteryStatusChip @JvmOverloads constructor(context: Context, attrs: Attri
 
     init {
         inflate(context, R.layout.battery_status_chip, this)
-        roundedContainer = findViewById(R.id.rounded_container)
-        batteryMeterView = findViewById(R.id.battery_meter_view)
+        roundedContainer = requireViewById(R.id.rounded_container)
+        batteryMeterView = requireViewById(R.id.battery_meter_view)
         updateResources()
     }
 
diff --git a/packages/SystemUI/src/com/android/systemui/statusbar/LightRevealScrim.kt b/packages/SystemUI/src/com/android/systemui/statusbar/LightRevealScrim.kt
index 5e449900248ac..3120128c79670 100644
--- a/packages/SystemUI/src/com/android/systemui/statusbar/LightRevealScrim.kt
+++ b/packages/SystemUI/src/com/android/systemui/statusbar/LightRevealScrim.kt
@@ -423,15 +423,14 @@ constructor(
         revealGradientCenter.y = top + (revealGradientHeight / 2f)
     }
 
-    override fun onDraw(canvas: Canvas?) {
+    override fun onDraw(canvas: Canvas) {
         if (
-            canvas == null ||
-                revealGradientWidth <= 0 ||
-                revealGradientHeight <= 0 ||
-                revealAmount == 0f
+            revealGradientWidth <= 0 ||
+            revealGradientHeight <= 0 ||
+            revealAmount == 0f
         ) {
             if (revealAmount < 1f) {
-                canvas?.drawColor(revealGradientEndColor)
+                canvas.drawColor(revealGradientEndColor)
             }
             return
         }
diff --git a/packages/SystemUI/src/com/android/systemui/statusbar/LockscreenShadeTransitionController.kt b/packages/SystemUI/src/com/android/systemui/statusbar/LockscreenShadeTransitionController.kt
index 4710574ac20dc..672796a513e99 100644
--- a/packages/SystemUI/src/com/android/systemui/statusbar/LockscreenShadeTransitionController.kt
+++ b/packages/SystemUI/src/com/android/systemui/statusbar/LockscreenShadeTransitionController.kt
@@ -474,7 +474,7 @@ class LockscreenShadeTransitionController @Inject constructor(
         }
         if (endlistener != null) {
             dragDownAnimator.addListener(object : AnimatorListenerAdapter() {
-                override fun onAnimationEnd(animation: Animator?) {
+                override fun onAnimationEnd(animation: Animator) {
                     endlistener.invoke()
                 }
             })
diff --git a/packages/SystemUI/src/com/android/systemui/statusbar/MediaArtworkProcessor.kt b/packages/SystemUI/src/com/android/systemui/statusbar/MediaArtworkProcessor.kt
index 750272d656598..17b4e3baef13c 100644
--- a/packages/SystemUI/src/com/android/systemui/statusbar/MediaArtworkProcessor.kt
+++ b/packages/SystemUI/src/com/android/systemui/statusbar/MediaArtworkProcessor.kt
@@ -66,7 +66,7 @@ class MediaArtworkProcessor @Inject constructor() {
                 inBitmap = oldIn.copy(Bitmap.Config.ARGB_8888, false /* isMutable */)
                 oldIn.recycle()
             }
-            val outBitmap = Bitmap.createBitmap(inBitmap.width, inBitmap.height,
+            val outBitmap = Bitmap.createBitmap(inBitmap?.width ?: 0, inBitmap?.height ?: 0,
                     Bitmap.Config.ARGB_8888)
 
             input = Allocation.createFromBitmap(renderScript, inBitmap,
diff --git a/packages/SystemUI/src/com/android/systemui/statusbar/NotificationShadeDepthController.kt b/packages/SystemUI/src/com/android/systemui/statusbar/NotificationShadeDepthController.kt
index 0e20df6ecfba0..6ad1395964a23 100644
--- a/packages/SystemUI/src/com/android/systemui/statusbar/NotificationShadeDepthController.kt
+++ b/packages/SystemUI/src/com/android/systemui/statusbar/NotificationShadeDepthController.kt
@@ -272,7 +272,7 @@ class NotificationShadeDepthController @Inject constructor(
                             blurUtils.blurRadiusOfRatio(animation.animatedValue as Float)
                 }
                 addListener(object : AnimatorListenerAdapter() {
-                    override fun onAnimationEnd(animation: Animator?) {
+                    override fun onAnimationEnd(animation: Animator) {
                         keyguardAnimator = null
                         wakeAndUnlockBlurRadius = 0f
                     }
diff --git a/packages/SystemUI/src/com/android/systemui/statusbar/events/PrivacyDotViewController.kt b/packages/SystemUI/src/com/android/systemui/statusbar/events/PrivacyDotViewController.kt
index eddb6835318d7..d1e0a7193948f 100644
--- a/packages/SystemUI/src/com/android/systemui/statusbar/events/PrivacyDotViewController.kt
+++ b/packages/SystemUI/src/com/android/systemui/statusbar/events/PrivacyDotViewController.kt
@@ -234,7 +234,7 @@ open class PrivacyDotViewController @Inject constructor(
             }
 
             // Set the dot's view gravity to hug the status bar
-            (corner.findViewById<View>(R.id.privacy_dot)
+            (corner.requireViewById<View>(R.id.privacy_dot)
                     .layoutParams as FrameLayout.LayoutParams)
                         .gravity = rotatedCorner.innerGravity()
         }
@@ -255,7 +255,7 @@ open class PrivacyDotViewController @Inject constructor(
         // in every rotation. The only thing we need to check is rtl
         val rtl = state.layoutRtl
         val size = Point()
-        tl.context.display.getRealSize(size)
+        tl.context.display?.getRealSize(size)
         val currentRotation = RotationUtils.getExactRotation(tl.context)
 
         val displayWidth: Int
diff --git a/packages/SystemUI/src/com/android/systemui/statusbar/lockscreen/LockscreenSmartspaceController.kt b/packages/SystemUI/src/com/android/systemui/statusbar/lockscreen/LockscreenSmartspaceController.kt
index 903d485369466..c5de16511aefe 100644
--- a/packages/SystemUI/src/com/android/systemui/statusbar/lockscreen/LockscreenSmartspaceController.kt
+++ b/packages/SystemUI/src/com/android/systemui/statusbar/lockscreen/LockscreenSmartspaceController.kt
@@ -179,15 +179,20 @@ constructor(
         }
         if (weatherTarget != null) {
             val clickIntent = weatherTarget.headerAction?.intent
-            val weatherData = WeatherData.fromBundle(weatherTarget.baseAction.extras, { v ->
-                if (!falsingManager.isFalseTap(FalsingManager.LOW_PENALTY)) {
-                    activityStarter.startActivity(
-                        clickIntent,
-                        true, /* dismissShade */
-                        null,
-                        false)
+            val weatherData = weatherTarget.baseAction?.extras?.let { extras ->
+                WeatherData.fromBundle(
+                    extras,
+                ) { _ ->
+                    if (!falsingManager.isFalseTap(FalsingManager.LOW_PENALTY)) {
+                        activityStarter.startActivity(
+                            clickIntent,
+                            true, /* dismissShade */
+                            null,
+                            false)
+                    }
                 }
-            })
+            }
+
             if (weatherData != null) {
                 keyguardUpdateMonitor.sendWeatherData(weatherData)
             }
diff --git a/packages/SystemUI/src/com/android/systemui/statusbar/notification/ViewGroupFadeHelper.kt b/packages/SystemUI/src/com/android/systemui/statusbar/notification/ViewGroupFadeHelper.kt
index 16f1a45ba83ff..1b43922f652ab 100644
--- a/packages/SystemUI/src/com/android/systemui/statusbar/notification/ViewGroupFadeHelper.kt
+++ b/packages/SystemUI/src/com/android/systemui/statusbar/notification/ViewGroupFadeHelper.kt
@@ -74,7 +74,7 @@ class ViewGroupFadeHelper {
                     root.setTag(R.id.view_group_fade_helper_previous_value_tag, newAlpha)
                 }
                 addListener(object : AnimatorListenerAdapter() {
-                    override fun onAnimationEnd(animation: Animator?) {
+                    override fun onAnimationEnd(animation: Animator) {
                         endRunnable?.run()
                     }
                 })
diff --git a/packages/SystemUI/src/com/android/systemui/statusbar/notification/row/ChannelEditorListView.kt b/packages/SystemUI/src/com/android/systemui/statusbar/notification/row/ChannelEditorListView.kt
index 38a1579222b1e..9c4aa072a83df 100644
--- a/packages/SystemUI/src/com/android/systemui/statusbar/notification/row/ChannelEditorListView.kt
+++ b/packages/SystemUI/src/com/android/systemui/statusbar/notification/row/ChannelEditorListView.kt
@@ -60,7 +60,7 @@ class ChannelEditorListView(c: Context, attrs: AttributeSet) : LinearLayout(c, a
     override fun onFinishInflate() {
         super.onFinishInflate()
 
-        appControlRow = findViewById(R.id.app_control)
+        appControlRow = requireViewById(R.id.app_control)
     }
 
     /**
@@ -143,9 +143,9 @@ class AppControlView(c: Context, attrs: AttributeSet) : LinearLayout(c, attrs) {
     lateinit var switch: Switch
 
     override fun onFinishInflate() {
-        iconView = findViewById(R.id.icon)
-        channelName = findViewById(R.id.app_name)
-        switch = findViewById(R.id.toggle)
+        iconView = requireViewById(R.id.icon)
+        channelName = requireViewById(R.id.app_name)
+        switch = requireViewById(R.id.toggle)
 
         setOnClickListener { switch.toggle() }
     }
@@ -174,9 +174,9 @@ class ChannelRow(c: Context, attrs: AttributeSet) : LinearLayout(c, attrs) {
 
     override fun onFinishInflate() {
         super.onFinishInflate()
-        channelName = findViewById(R.id.channel_name)
-        channelDescription = findViewById(R.id.channel_description)
-        switch = findViewById(R.id.toggle)
+        channelName = requireViewById(R.id.channel_name)
+        channelDescription = requireViewById(R.id.channel_description)
+        switch = requireViewById(R.id.toggle)
         switch.setOnCheckedChangeListener { _, b ->
             channel?.let {
                 controller.proposeEditForChannel(it, if (b) it.importance else IMPORTANCE_NONE)
diff --git a/packages/SystemUI/src/com/android/systemui/statusbar/phone/ActivityStarterImpl.kt b/packages/SystemUI/src/com/android/systemui/statusbar/phone/ActivityStarterImpl.kt
index 2ccbc9f2f017b..baeae79f4d7d5 100644
--- a/packages/SystemUI/src/com/android/systemui/statusbar/phone/ActivityStarterImpl.kt
+++ b/packages/SystemUI/src/com/android/systemui/statusbar/phone/ActivityStarterImpl.kt
@@ -914,8 +914,8 @@ constructor(
             val packages: Array<String> =
                 context.resources.getStringArray(R.array.system_ui_packages)
             for (pkg in packages) {
-                if (intent.component == null) break
-                if (pkg == intent.component.packageName) {
+                val componentName = intent.component ?: break
+                if (pkg == componentName.packageName) {
                     return UserHandle(UserHandle.myUserId())
                 }
             }
diff --git a/packages/SystemUI/src/com/android/systemui/statusbar/phone/KeyguardBottomAreaView.kt b/packages/SystemUI/src/com/android/systemui/statusbar/phone/KeyguardBottomAreaView.kt
index 34bbd1359df72..cdd410e766a24 100644
--- a/packages/SystemUI/src/com/android/systemui/statusbar/phone/KeyguardBottomAreaView.kt
+++ b/packages/SystemUI/src/com/android/systemui/statusbar/phone/KeyguardBottomAreaView.kt
@@ -32,6 +32,7 @@ import com.android.systemui.keyguard.ui.viewmodel.KeyguardBottomAreaViewModel
 import com.android.systemui.plugins.ActivityStarter
 import com.android.systemui.plugins.FalsingManager
 import com.android.systemui.statusbar.VibratorHelper
+import com.android.systemui.util.animation.requiresRemeasuring
 
 /**
  * Renders the bottom area of the lock-screen. Concerned primarily with the quick affordance UI
@@ -98,7 +99,7 @@ constructor(
         ambientIndicationArea?.let { nonNullAmbientIndicationArea ->
             // remove old ambient indication from its parent
             val originalAmbientIndicationView =
-                oldBottomArea.findViewById<View>(R.id.ambient_indication_container)
+                oldBottomArea.requireViewById<View>(R.id.ambient_indication_container)
             (originalAmbientIndicationView.parent as ViewGroup).removeView(
                 originalAmbientIndicationView
             )
diff --git a/packages/SystemUI/src/com/android/systemui/statusbar/phone/PhoneStatusBarViewController.kt b/packages/SystemUI/src/com/android/systemui/statusbar/phone/PhoneStatusBarViewController.kt
index 2affb8173a01d..931aedd905425 100644
--- a/packages/SystemUI/src/com/android/systemui/statusbar/phone/PhoneStatusBarViewController.kt
+++ b/packages/SystemUI/src/com/android/systemui/statusbar/phone/PhoneStatusBarViewController.kt
@@ -75,13 +75,13 @@ class PhoneStatusBarViewController private constructor(
     }
 
     override fun onViewAttached() {
-        statusContainer = mView.findViewById(R.id.system_icons)
+        statusContainer = mView.requireViewById(R.id.system_icons)
         statusContainer.setOnHoverListener(
             statusOverlayHoverListenerFactory.createDarkAwareListener(statusContainer))
         if (moveFromCenterAnimationController == null) return
 
-        val statusBarLeftSide: View = mView.findViewById(R.id.status_bar_start_side_except_heads_up)
-        val systemIconArea: ViewGroup = mView.findViewById(R.id.status_bar_end_side_content)
+        val statusBarLeftSide: View = mView.requireViewById(R.id.status_bar_start_side_except_heads_up)
+        val systemIconArea: ViewGroup = mView.requireViewById(R.id.status_bar_end_side_content)
 
         val viewsToAnimate = arrayOf(
             statusBarLeftSide,
diff --git a/packages/SystemUI/src/com/android/systemui/statusbar/phone/StatusBarContentInsetsProvider.kt b/packages/SystemUI/src/com/android/systemui/statusbar/phone/StatusBarContentInsetsProvider.kt
index c850d4f9c56b3..ad18170192849 100644
--- a/packages/SystemUI/src/com/android/systemui/statusbar/phone/StatusBarContentInsetsProvider.kt
+++ b/packages/SystemUI/src/com/android/systemui/statusbar/phone/StatusBarContentInsetsProvider.kt
@@ -117,11 +117,11 @@ class StatusBarContentInsetsProvider @Inject constructor(
      * status bar area is contiguous.
      */
     fun currentRotationHasCornerCutout(): Boolean {
-        val cutout = context.display.cutout ?: return false
+        val cutout = checkNotNull(context.display).cutout ?: return false
         val topBounds = cutout.boundingRectTop
 
         val point = Point()
-        context.display.getRealSize(point)
+        checkNotNull(context.display).getRealSize(point)
 
         return topBounds.left <= 0 || topBounds.right >= point.x
     }
@@ -161,7 +161,7 @@ class StatusBarContentInsetsProvider @Inject constructor(
      */
     fun getStatusBarContentInsetsForRotation(@Rotation rotation: Int): Pair<Int, Int> =
         traceSection(tag = "StatusBarContentInsetsProvider.getStatusBarContentInsetsForRotation") {
-            val displayCutout = context.display.cutout
+            val displayCutout = checkNotNull(context.display).cutout
             val key = getCacheKey(rotation, displayCutout)
 
             val screenBounds = context.resources.configuration.windowConfiguration.maxBounds
@@ -198,7 +198,7 @@ class StatusBarContentInsetsProvider @Inject constructor(
     fun getStatusBarContentAreaForRotation(
         @Rotation rotation: Int
     ): Rect {
-        val displayCutout = context.display.cutout
+        val displayCutout = checkNotNull(context.display).cutout
         val key = getCacheKey(rotation, displayCutout)
         return insetsCache[key] ?: getAndSetCalculatedAreaForRotation(
                 rotation, displayCutout, getResourcesForRotation(rotation, context), key)
diff --git a/packages/SystemUI/src/com/android/systemui/statusbar/phone/UnlockedScreenOffAnimationController.kt b/packages/SystemUI/src/com/android/systemui/statusbar/phone/UnlockedScreenOffAnimationController.kt
index e8da9519c7efa..1bceb29dc85de 100644
--- a/packages/SystemUI/src/com/android/systemui/statusbar/phone/UnlockedScreenOffAnimationController.kt
+++ b/packages/SystemUI/src/com/android/systemui/statusbar/phone/UnlockedScreenOffAnimationController.kt
@@ -105,18 +105,18 @@ class UnlockedScreenOffAnimationController @Inject constructor(
             }
         }
         addListener(object : AnimatorListenerAdapter() {
-            override fun onAnimationCancel(animation: Animator?) {
+            override fun onAnimationCancel(animation: Animator) {
                 if (lightRevealScrim.revealEffect !is CircleReveal) {
                     lightRevealScrim.revealAmount = 1f
                 }
             }
 
-            override fun onAnimationEnd(animation: Animator?) {
+            override fun onAnimationEnd(animation: Animator) {
                 lightRevealAnimationPlaying = false
                 interactionJankMonitor.end(CUJ_SCREEN_OFF)
             }
 
-            override fun onAnimationStart(animation: Animator?) {
+            override fun onAnimationStart(animation: Animator) {
                 interactionJankMonitor.begin(
                         notifShadeWindowControllerLazy.get().windowRootView, CUJ_SCREEN_OFF)
             }
@@ -345,7 +345,7 @@ class UnlockedScreenOffAnimationController @Inject constructor(
         // portrait. If we're in another orientation, disable the screen off animation so we don't
         // animate in the keyguard AOD UI sideways or upside down.
         if (!keyguardStateController.isKeyguardScreenRotationAllowed &&
-            context.display.rotation != Surface.ROTATION_0) {
+            context.display?.rotation != Surface.ROTATION_0) {
             return false
         }
 
diff --git a/packages/SystemUI/src/com/android/systemui/statusbar/phone/userswitcher/StatusBarUserSwitcherContainer.kt b/packages/SystemUI/src/com/android/systemui/statusbar/phone/userswitcher/StatusBarUserSwitcherContainer.kt
index 270c592ae4fd4..12594771a0df2 100644
--- a/packages/SystemUI/src/com/android/systemui/statusbar/phone/userswitcher/StatusBarUserSwitcherContainer.kt
+++ b/packages/SystemUI/src/com/android/systemui/statusbar/phone/userswitcher/StatusBarUserSwitcherContainer.kt
@@ -34,7 +34,7 @@ class StatusBarUserSwitcherContainer(
 
     override fun onFinishInflate() {
         super.onFinishInflate()
-        text = findViewById(R.id.current_user_name)
-        avatar = findViewById(R.id.current_user_avatar)
+        text = requireViewById(R.id.current_user_name)
+        avatar = requireViewById(R.id.current_user_avatar)
     }
 }
\ No newline at end of file
diff --git a/packages/SystemUI/src/com/android/systemui/statusbar/policy/DeviceControlsControllerImpl.kt b/packages/SystemUI/src/com/android/systemui/statusbar/policy/DeviceControlsControllerImpl.kt
index 49504827e073d..ffb743ff926c1 100644
--- a/packages/SystemUI/src/com/android/systemui/statusbar/policy/DeviceControlsControllerImpl.kt
+++ b/packages/SystemUI/src/com/android/systemui/statusbar/policy/DeviceControlsControllerImpl.kt
@@ -128,7 +128,8 @@ public class DeviceControlsControllerImpl @Inject constructor(
 
         val prefs = userContextProvider.userContext.getSharedPreferences(
             PREFS_CONTROLS_FILE, Context.MODE_PRIVATE)
-        val seededPackages = prefs.getStringSet(PREFS_CONTROLS_SEEDING_COMPLETED, emptySet())
+        val seededPackages =
+            prefs.getStringSet(PREFS_CONTROLS_SEEDING_COMPLETED, emptySet()) ?: emptySet()
 
         val controlsController = controlsComponent.getControlsController().get()
         val componentsToSeed = mutableListOf<ComponentName>()
@@ -174,7 +175,8 @@ public class DeviceControlsControllerImpl @Inject constructor(
     }
 
     private fun addPackageToSeededSet(prefs: SharedPreferences, pkg: String) {
-        val seededPackages = prefs.getStringSet(PREFS_CONTROLS_SEEDING_COMPLETED, emptySet())
+        val seededPackages =
+            prefs.getStringSet(PREFS_CONTROLS_SEEDING_COMPLETED, emptySet()) ?: emptySet()
         val updatedPkgs = seededPackages.toMutableSet()
         updatedPkgs.add(pkg)
         prefs.edit().putStringSet(PREFS_CONTROLS_SEEDING_COMPLETED, updatedPkgs).apply()
diff --git a/packages/SystemUI/src/com/android/systemui/stylus/StylusManager.kt b/packages/SystemUI/src/com/android/systemui/stylus/StylusManager.kt
index 27aaa68280362..eb7d339f5b423 100644
--- a/packages/SystemUI/src/com/android/systemui/stylus/StylusManager.kt
+++ b/packages/SystemUI/src/com/android/systemui/stylus/StylusManager.kt
@@ -353,8 +353,8 @@ constructor(
                     // before CoreStartables run, and will not be removed.
                     // In many cases, it reports the battery level of the stylus.
                     registerBatteryListener(deviceId)
-                } else if (device.bluetoothAddress != null) {
-                    onStylusBluetoothConnected(deviceId, device.bluetoothAddress)
+                } else {
+                    device.bluetoothAddress?.let { onStylusBluetoothConnected(deviceId, it) }
                 }
             }
         }
diff --git a/packages/SystemUI/src/com/android/systemui/user/UserSwitcherFullscreenDialog.kt b/packages/SystemUI/src/com/android/systemui/user/UserSwitcherFullscreenDialog.kt
index 72786efc416db..5ad963035e36f 100644
--- a/packages/SystemUI/src/com/android/systemui/user/UserSwitcherFullscreenDialog.kt
+++ b/packages/SystemUI/src/com/android/systemui/user/UserSwitcherFullscreenDialog.kt
@@ -60,7 +60,7 @@ class UserSwitchFullscreenDialog(
 
     override fun getWidth(): Int {
         val displayMetrics = context.resources.displayMetrics.apply {
-            context.display.getRealMetrics(this)
+            checkNotNull(context.display).getRealMetrics(this)
         }
         return displayMetrics.widthPixels
     }
diff --git a/packages/SystemUI/src/com/android/systemui/user/UserSwitcherPopupMenu.kt b/packages/SystemUI/src/com/android/systemui/user/UserSwitcherPopupMenu.kt
index 088cd93bdf7e5..ee84580ac4ecb 100644
--- a/packages/SystemUI/src/com/android/systemui/user/UserSwitcherPopupMenu.kt
+++ b/packages/SystemUI/src/com/android/systemui/user/UserSwitcherPopupMenu.kt
@@ -52,22 +52,22 @@ class UserSwitcherPopupMenu(
     override fun show() {
         // need to call show() first in order to construct the listView
         super.show()
-        val listView = getListView()
+        listView?.apply {
+            isVerticalScrollBarEnabled = false
+            isHorizontalScrollBarEnabled = false
 
-        listView.setVerticalScrollBarEnabled(false)
-        listView.setHorizontalScrollBarEnabled(false)
+            // Creates a transparent spacer between items
+            val shape = ShapeDrawable()
+            shape.alpha = 0
+            divider = shape
+            dividerHeight = res.getDimensionPixelSize(
+                R.dimen.bouncer_user_switcher_popup_divider_height)
 
-        // Creates a transparent spacer between items
-        val shape = ShapeDrawable()
-        shape.setAlpha(0)
-        listView.setDivider(shape)
-        listView.setDividerHeight(res.getDimensionPixelSize(
-            R.dimen.bouncer_user_switcher_popup_divider_height))
-
-        val height = res.getDimensionPixelSize(R.dimen.bouncer_user_switcher_popup_header_height)
-        listView.addHeaderView(createSpacer(height), null, false)
-        listView.addFooterView(createSpacer(height), null, false)
-        setWidth(findMaxWidth(listView))
+            val height = res.getDimensionPixelSize(R.dimen.bouncer_user_switcher_popup_header_height)
+            addHeaderView(createSpacer(height), null, false)
+            addFooterView(createSpacer(height), null, false)
+            setWidth(findMaxWidth(this))
+        }
 
         super.show()
     }
diff --git a/packages/SystemUI/src/com/android/systemui/user/legacyhelper/ui/LegacyUserUiHelper.kt b/packages/SystemUI/src/com/android/systemui/user/legacyhelper/ui/LegacyUserUiHelper.kt
index e74232df3ac36..7f16e47abce13 100644
--- a/packages/SystemUI/src/com/android/systemui/user/legacyhelper/ui/LegacyUserUiHelper.kt
+++ b/packages/SystemUI/src/com/android/systemui/user/legacyhelper/ui/LegacyUserUiHelper.kt
@@ -67,7 +67,7 @@ object LegacyUserUiHelper {
         val resourceId: Int? = getGuestUserRecordNameResourceId(record)
         return when {
             resourceId != null -> context.getString(resourceId)
-            record.info != null -> record.info.name
+            record.info != null -> checkNotNull(record.info.name)
             else ->
                 context.getString(
                     getUserSwitcherActionTextResourceId(
diff --git a/packages/SystemUI/src/com/android/systemui/util/animation/TransitionLayout.kt b/packages/SystemUI/src/com/android/systemui/util/animation/TransitionLayout.kt
index 56c5d3b433ff6..7866d7673937b 100644
--- a/packages/SystemUI/src/com/android/systemui/util/animation/TransitionLayout.kt
+++ b/packages/SystemUI/src/com/android/systemui/util/animation/TransitionLayout.kt
@@ -223,11 +223,11 @@ class TransitionLayout @JvmOverloads constructor(
         }
     }
 
-    override fun dispatchDraw(canvas: Canvas?) {
-        canvas?.save()
-        canvas?.clipRect(boundsRect)
+    override fun dispatchDraw(canvas: Canvas) {
+        canvas.save()
+        canvas.clipRect(boundsRect)
         super.dispatchDraw(canvas)
-        canvas?.restore()
+        canvas.restore()
     }
 
     private fun updateBounds() {
diff --git a/packages/SystemUI/tests/src/com/android/systemui/biometrics/SideFpsControllerTest.kt b/packages/SystemUI/tests/src/com/android/systemui/biometrics/SideFpsControllerTest.kt
index 2b08c66c96fa4..994db460cdbbe 100644
--- a/packages/SystemUI/tests/src/com/android/systemui/biometrics/SideFpsControllerTest.kt
+++ b/packages/SystemUI/tests/src/com/android/systemui/biometrics/SideFpsControllerTest.kt
@@ -164,7 +164,7 @@ class SideFpsControllerTest : SysuiTestCase() {
         context.addMockSystemService(WindowManager::class.java, windowManager)
 
         whenEver(layoutInflater.inflate(R.layout.sidefps_view, null, false)).thenReturn(sideFpsView)
-        whenEver(sideFpsView.findViewById<LottieAnimationView>(eq(R.id.sidefps_animation)))
+        whenEver(sideFpsView.requireViewById<LottieAnimationView>(eq(R.id.sidefps_animation)))
             .thenReturn(mock(LottieAnimationView::class.java))
         with(mock(ViewPropertyAnimator::class.java)) {
             whenEver(sideFpsView.animate()).thenReturn(this)
diff --git a/packages/SystemUI/tests/src/com/android/systemui/shade/ShadeHeaderControllerTest.kt b/packages/SystemUI/tests/src/com/android/systemui/shade/ShadeHeaderControllerTest.kt
index 2501f85798aaa..8f8b840b03c91 100644
--- a/packages/SystemUI/tests/src/com/android/systemui/shade/ShadeHeaderControllerTest.kt
+++ b/packages/SystemUI/tests/src/com/android/systemui/shade/ShadeHeaderControllerTest.kt
@@ -138,19 +138,19 @@ class ShadeHeaderControllerTest : SysuiTestCase() {
 
     @Before
     fun setup() {
-        whenever<Clock>(view.findViewById(R.id.clock)).thenReturn(clock)
+        whenever<Clock>(view.requireViewById(R.id.clock)).thenReturn(clock)
         whenever(clock.context).thenReturn(mockedContext)
 
-        whenever<TextView>(view.findViewById(R.id.date)).thenReturn(date)
+        whenever<TextView>(view.requireViewById(R.id.date)).thenReturn(date)
         whenever(date.context).thenReturn(mockedContext)
 
-        whenever<ShadeCarrierGroup>(view.findViewById(R.id.carrier_group)).thenReturn(carrierGroup)
+        whenever<ShadeCarrierGroup>(view.requireViewById(R.id.carrier_group)).thenReturn(carrierGroup)
 
-        whenever<BatteryMeterView>(view.findViewById(R.id.batteryRemainingIcon))
+        whenever<BatteryMeterView>(view.requireViewById(R.id.batteryRemainingIcon))
             .thenReturn(batteryMeterView)
 
-        whenever<StatusIconContainer>(view.findViewById(R.id.statusIcons)).thenReturn(statusIcons)
-        whenever<View>(view.findViewById(R.id.shade_header_system_icons)).thenReturn(systemIcons)
+        whenever<StatusIconContainer>(view.requireViewById(R.id.statusIcons)).thenReturn(statusIcons)
+        whenever<View>(view.requireViewById(R.id.shade_header_system_icons)).thenReturn(systemIcons)
 
         viewContext = Mockito.spy(context)
         whenever(view.context).thenReturn(viewContext)