diff --git a/packages/SystemUI/plugin/src/com/android/systemui/plugins/ClockProviderPlugin.kt b/packages/SystemUI/plugin/src/com/android/systemui/plugins/ClockProviderPlugin.kt
index 4889dbd239133..01e5d86549ebd 100644
--- a/packages/SystemUI/plugin/src/com/android/systemui/plugins/ClockProviderPlugin.kt
+++ b/packages/SystemUI/plugin/src/com/android/systemui/plugins/ClockProviderPlugin.kt
@@ -61,11 +61,7 @@ interface Clock {
 
     /** Initializes various rendering parameters. If never called, provides reasonable defaults. */
     fun initialize(resources: Resources, dozeFraction: Float, foldFraction: Float) {
-        events.onColorPaletteChanged(
-                resources,
-                ClockDarkness.DEFAULT,
-                ClockDarkness.DEFAULT
-        )
+        events.onColorPaletteChanged(resources, true, true)
         animations.doze(dozeFraction)
         animations.fold(foldFraction)
         events.onTimeTick()
@@ -95,8 +91,8 @@ interface ClockEvents {
     /** Call whenever the color palette should update */
     fun onColorPaletteChanged(
             resources: Resources,
-            smallClockIsDark: ClockDarkness,
-            largeClockIsDark: ClockDarkness
+            smallClockIsDark: Boolean,
+            largeClockIsDark: Boolean
     ) { }
 }
 
@@ -120,12 +116,3 @@ data class ClockMetadata(
     val clockId: ClockId,
     val name: String
 )
-
-/**
- * Enum for whether clock region is dark or light.
- */
-enum class ClockDarkness(val isDark: Boolean) {
-    DEFAULT(true),
-    DARK(true),
-    LIGHT(false)
-}
diff --git a/packages/SystemUI/res-keyguard/layout/keyguard_clock_switch.xml b/packages/SystemUI/res-keyguard/layout/keyguard_clock_switch.xml
index 8b8ebf00e190d..3ad7c8c4369ca 100644
--- a/packages/SystemUI/res-keyguard/layout/keyguard_clock_switch.xml
+++ b/packages/SystemUI/res-keyguard/layout/keyguard_clock_switch.xml
@@ -23,6 +23,7 @@
     android:id="@+id/keyguard_clock_container"
     android:layout_width="match_parent"
     android:layout_height="wrap_content"
+    android:clipChildren="false"
     android:layout_gravity="center_horizontal|top">
     <FrameLayout
         android:id="@+id/lockscreen_clock_view"
@@ -30,16 +31,13 @@
         android:layout_height="wrap_content"
         android:layout_alignParentStart="true"
         android:layout_alignParentTop="true"
-        android:paddingStart="@dimen/clock_padding_start">
-    </FrameLayout>
+        android:paddingStart="@dimen/clock_padding_start" />
     <FrameLayout
         android:id="@+id/lockscreen_clock_view_large"
         android:layout_width="match_parent"
         android:layout_height="match_parent"
-        android:layout_below="@id/keyguard_slice_view"
-        android:paddingTop="@dimen/keyguard_large_clock_top_padding"
-        android:visibility="gone">
-    </FrameLayout>
+        android:layout_marginTop="@dimen/keyguard_large_clock_top_margin"
+        android:visibility="gone" />
 
     <!-- Not quite optimal but needed to translate these items as a group. The
          NotificationIconContainer has its own logic for translation. -->
diff --git a/packages/SystemUI/res/values/dimens.xml b/packages/SystemUI/res/values/dimens.xml
index a77575418e5f2..e3be36503c873 100644
--- a/packages/SystemUI/res/values/dimens.xml
+++ b/packages/SystemUI/res/values/dimens.xml
@@ -669,7 +669,7 @@
     <!-- When large clock is showing, offset the smartspace by this amount -->
     <dimen name="keyguard_smartspace_top_offset">12dp</dimen>
     <!-- With the large clock, move up slightly from the center -->
-    <dimen name="keyguard_large_clock_top_padding">100dp</dimen>
+    <dimen name="keyguard_large_clock_top_margin">-60dp</dimen>
 
     <dimen name="notification_scrim_corner_radius">32dp</dimen>
 
diff --git a/packages/SystemUI/shared/res/layout/clock_default_small.xml b/packages/SystemUI/shared/res/layout/clock_default_small.xml
index 390ff5e3ff787..ff6d7f9e22403 100644
--- a/packages/SystemUI/shared/res/layout/clock_default_small.xml
+++ b/packages/SystemUI/shared/res/layout/clock_default_small.xml
@@ -18,7 +18,7 @@
 -->
 <com.android.systemui.shared.clocks.AnimatableClockView
     xmlns:android="http://schemas.android.com/apk/res/android"
-    android:layout_width="wrap_content"
+    android:layout_width="match_parent"
     android:layout_height="wrap_content"
     android:layout_gravity="start"
     android:gravity="start"
diff --git a/packages/SystemUI/shared/src/com/android/systemui/shared/clocks/AnimatableClockView.kt b/packages/SystemUI/shared/src/com/android/systemui/shared/clocks/AnimatableClockView.kt
index 580d45375afb2..b3b75f68e71e8 100644
--- a/packages/SystemUI/shared/src/com/android/systemui/shared/clocks/AnimatableClockView.kt
+++ b/packages/SystemUI/shared/src/com/android/systemui/shared/clocks/AnimatableClockView.kt
@@ -29,6 +29,7 @@ import android.util.AttributeSet
 import android.widget.TextView
 import com.android.internal.R.attr.contentDescription
 import com.android.internal.R.attr.format
+import com.android.internal.annotations.VisibleForTesting
 import com.android.systemui.animation.GlyphCallback
 import com.android.systemui.animation.Interpolators
 import com.android.systemui.animation.TextAnimator
@@ -77,7 +78,8 @@ class AnimatableClockView @JvmOverloads constructor(
     private var textAnimator: TextAnimator? = null
     private var onTextAnimatorInitialized: Runnable? = null
 
-    var timeOverrideInMillis: Long? = null
+    @VisibleForTesting var isAnimationEnabled: Boolean = true
+    @VisibleForTesting var timeOverrideInMillis: Long? = null
 
     val dozingWeight: Int
         get() = if (useBoldedVersion()) dozingWeightInternal + 100 else dozingWeightInternal
@@ -218,7 +220,7 @@ class AnimatableClockView @JvmOverloads constructor(
     }
 
     fun animateAppearOnLockscreen() {
-        if (textAnimator == null) {
+        if (isAnimationEnabled && textAnimator == null) {
             return
         }
         setTextStyle(
@@ -234,7 +236,7 @@ class AnimatableClockView @JvmOverloads constructor(
             weight = lockScreenWeight,
             textSize = -1f,
             color = lockScreenColor,
-            animate = true,
+            animate = isAnimationEnabled,
             duration = APPEAR_ANIM_DURATION,
             delay = 0,
             onAnimationEnd = null
@@ -242,7 +244,7 @@ class AnimatableClockView @JvmOverloads constructor(
     }
 
     fun animateFoldAppear(animate: Boolean = true) {
-        if (textAnimator == null) {
+        if (isAnimationEnabled && textAnimator == null) {
             return
         }
         setTextStyle(
@@ -258,7 +260,7 @@ class AnimatableClockView @JvmOverloads constructor(
             weight = dozingWeightInternal,
             textSize = -1f,
             color = dozingColor,
-            animate = animate,
+            animate = animate && isAnimationEnabled,
             interpolator = Interpolators.EMPHASIZED_DECELERATE,
             duration = ANIMATION_DURATION_FOLD_TO_AOD.toLong(),
             delay = 0,
@@ -276,7 +278,7 @@ class AnimatableClockView @JvmOverloads constructor(
                 weight = if (isDozing()) dozingWeight else lockScreenWeight,
                 textSize = -1f,
                 color = null,
-                animate = true,
+                animate = isAnimationEnabled,
                 duration = CHARGE_ANIM_DURATION_PHASE_1,
                 delay = 0,
                 onAnimationEnd = null
@@ -286,7 +288,7 @@ class AnimatableClockView @JvmOverloads constructor(
             weight = if (isDozing()) lockScreenWeight else dozingWeight,
             textSize = -1f,
             color = null,
-            animate = true,
+            animate = isAnimationEnabled,
             duration = CHARGE_ANIM_DURATION_PHASE_0,
             delay = chargeAnimationDelay.toLong(),
             onAnimationEnd = startAnimPhase2
@@ -298,7 +300,7 @@ class AnimatableClockView @JvmOverloads constructor(
             weight = if (isDozing) dozingWeight else lockScreenWeight,
             textSize = -1f,
             color = if (isDozing) dozingColor else lockScreenColor,
-            animate = animate,
+            animate = animate && isAnimationEnabled,
             duration = DOZE_ANIM_DURATION,
             delay = 0,
             onAnimationEnd = null
@@ -332,7 +334,7 @@ class AnimatableClockView @JvmOverloads constructor(
                 weight = weight,
                 textSize = textSize,
                 color = color,
-                animate = animate,
+                animate = animate && isAnimationEnabled,
                 duration = duration,
                 interpolator = interpolator,
                 delay = delay,
@@ -370,7 +372,7 @@ class AnimatableClockView @JvmOverloads constructor(
             weight = weight,
             textSize = textSize,
             color = color,
-            animate = animate,
+            animate = animate && isAnimationEnabled,
             interpolator = null,
             duration = duration,
             delay = delay,
diff --git a/packages/SystemUI/shared/src/com/android/systemui/shared/clocks/DefaultClockProvider.kt b/packages/SystemUI/shared/src/com/android/systemui/shared/clocks/DefaultClockProvider.kt
index b95e52dce2087..b5e57667fbb83 100644
--- a/packages/SystemUI/shared/src/com/android/systemui/shared/clocks/DefaultClockProvider.kt
+++ b/packages/SystemUI/shared/src/com/android/systemui/shared/clocks/DefaultClockProvider.kt
@@ -13,16 +13,18 @@
  */
 package com.android.systemui.shared.clocks
 
+import android.content.Context
 import android.content.res.Resources
 import android.graphics.Color
 import android.graphics.drawable.Drawable
 import android.icu.text.NumberFormat
 import android.util.TypedValue
 import android.view.LayoutInflater
+import android.widget.FrameLayout
+import com.android.internal.annotations.VisibleForTesting
 import com.android.systemui.dagger.qualifiers.Main
 import com.android.systemui.plugins.Clock
 import com.android.systemui.plugins.ClockAnimations
-import com.android.systemui.plugins.ClockDarkness
 import com.android.systemui.plugins.ClockEvents
 import com.android.systemui.plugins.ClockId
 import com.android.systemui.plugins.ClockMetadata
@@ -39,6 +41,7 @@ const val DEFAULT_CLOCK_ID = "DEFAULT"
 
 /** Provides the default system clock */
 class DefaultClockProvider @Inject constructor(
+    val ctx: Context,
     val layoutInflater: LayoutInflater,
     @Main val resources: Resources
 ) : ClockProvider {
@@ -49,7 +52,7 @@ class DefaultClockProvider @Inject constructor(
         if (id != DEFAULT_CLOCK_ID) {
             throw IllegalArgumentException("$id is unsupported by $TAG")
         }
-        return DefaultClock(layoutInflater, resources)
+        return DefaultClock(ctx, layoutInflater, resources)
     }
 
     override fun getClockThumbnail(id: ClockId): Drawable? {
@@ -69,14 +72,13 @@ class DefaultClockProvider @Inject constructor(
  * AnimatableClockView used by the existing lockscreen clock.
  */
 class DefaultClock(
+        ctx: Context,
         private val layoutInflater: LayoutInflater,
         private val resources: Resources
 ) : Clock {
-    override val smallClock =
-        layoutInflater.inflate(R.layout.clock_default_small, null) as AnimatableClockView
-    override val largeClock =
-        layoutInflater.inflate(R.layout.clock_default_large, null) as AnimatableClockView
-    private val clocks = listOf(smallClock, largeClock)
+    override val smallClock: AnimatableClockView
+    override val largeClock: AnimatableClockView
+    private val clocks get() = listOf(smallClock, largeClock)
 
     private val burmeseNf = NumberFormat.getInstance(Locale.forLanguageTag("my"))
     private val burmeseNumerals = burmeseNf.format(FORMAT_NUMBER.toLong())
@@ -84,17 +86,43 @@ class DefaultClock(
         resources.getFloat(R.dimen.keyguard_clock_line_spacing_scale_burmese)
     private val defaultLineSpacing = resources.getFloat(R.dimen.keyguard_clock_line_spacing_scale)
 
-    private fun updateClockColor(clock: AnimatableClockView, darkValue: ClockDarkness) {
-        val color = if (darkValue.isDark) {
-            resources.getColor(android.R.color.system_accent2_600)
-        } else {
-            resources.getColor(android.R.color.system_accent1_100)
-        }
-        clock.setColors(DOZE_COLOR, color)
-        clock.animateAppearOnLockscreen()
+    override val events: ClockEvents
+    override lateinit var animations: ClockAnimations
+        private set
+
+    init {
+        val parent = FrameLayout(ctx)
+
+        smallClock = layoutInflater.inflate(
+            R.layout.clock_default_small,
+            parent,
+            false
+        ) as AnimatableClockView
+
+        largeClock = layoutInflater.inflate(
+            R.layout.clock_default_large,
+            parent,
+            false
+        ) as AnimatableClockView
+
+        events = DefaultClockEvents()
+        animations = DefaultClockAnimations(0f, 0f)
+
+        events.onLocaleChanged(Locale.getDefault())
+
+        // DOZE_COLOR is a placeholder, and will be assigned correctly in initialize
+        clocks.forEach { it.setColors(DOZE_COLOR, DOZE_COLOR) }
     }
 
-    override val events = object : ClockEvents {
+    override fun initialize(resources: Resources, dozeFraction: Float, foldFraction: Float) {
+        recomputePadding()
+        animations = DefaultClockAnimations(dozeFraction, foldFraction)
+        events.onColorPaletteChanged(resources, true, true)
+        events.onTimeZoneChanged(TimeZone.getDefault())
+        events.onTimeTick()
+    }
+
+    inner class DefaultClockEvents() : ClockEvents {
         override fun onTimeTick() = clocks.forEach { it.refreshTime() }
 
         override fun onTimeFormatChanged(is24Hr: Boolean) =
@@ -117,8 +145,8 @@ class DefaultClock(
 
         override fun onColorPaletteChanged(
                 resources: Resources,
-                smallClockIsDark: ClockDarkness,
-                largeClockIsDark: ClockDarkness
+                smallClockIsDark: Boolean,
+                largeClockIsDark: Boolean
         ) {
             updateClockColor(smallClock, smallClockIsDark)
             updateClockColor(largeClock, largeClockIsDark)
@@ -136,9 +164,6 @@ class DefaultClock(
         }
     }
 
-    override var animations = DefaultClockAnimations(0f, 0f)
-        private set
-
     inner class DefaultClockAnimations(
         dozeFraction: Float,
         foldFraction: Float
@@ -194,31 +219,26 @@ class DefaultClock(
         }
     }
 
-    init {
-        events.onLocaleChanged(Locale.getDefault())
-        clocks.forEach { it.setColors(DOZE_COLOR, DOZE_COLOR) }
-    }
-
-    override fun initialize(resources: Resources, dozeFraction: Float, foldFraction: Float) {
-        recomputePadding()
-        animations = DefaultClockAnimations(dozeFraction, foldFraction)
-        events.onColorPaletteChanged(
-                resources,
-                ClockDarkness.DEFAULT,
-                ClockDarkness.DEFAULT
-        )
-        events.onTimeTick()
+    private fun updateClockColor(clock: AnimatableClockView, isRegionDark: Boolean) {
+        val color = if (isRegionDark) {
+            resources.getColor(android.R.color.system_accent1_100)
+        } else {
+            resources.getColor(android.R.color.system_accent2_600)
+        }
+        clock.setColors(DOZE_COLOR, color)
+        clock.animateAppearOnLockscreen()
     }
 
     private fun recomputePadding() {
-        val topPadding = -1 * (largeClock.bottom.toInt() - 180)
-        largeClock.setPadding(0, topPadding, 0, 0)
+        val lp = largeClock.getLayoutParams() as FrameLayout.LayoutParams
+        lp.topMargin = (-0.5f * largeClock.bottom).toInt()
+        largeClock.setLayoutParams(lp)
     }
 
     override fun dump(pw: PrintWriter) = clocks.forEach { it.dump(pw) }
 
     companion object {
-        private const val DOZE_COLOR = Color.WHITE
+        @VisibleForTesting const val DOZE_COLOR = Color.WHITE
         private const val FORMAT_NUMBER = 1234567890
     }
 }
diff --git a/packages/SystemUI/src/com/android/keyguard/ClockEventController.kt b/packages/SystemUI/src/com/android/keyguard/ClockEventController.kt
index 1e62b9c3abb39..0e1e0cb2adcf0 100644
--- a/packages/SystemUI/src/com/android/keyguard/ClockEventController.kt
+++ b/packages/SystemUI/src/com/android/keyguard/ClockEventController.kt
@@ -20,17 +20,16 @@ import android.content.Context
 import android.content.Intent
 import android.content.IntentFilter
 import android.content.res.Resources
-import android.graphics.Rect
 import android.text.format.DateFormat
+import android.util.TypedValue
 import android.view.View
 import com.android.systemui.broadcast.BroadcastDispatcher
 import com.android.systemui.dagger.qualifiers.Background
 import com.android.systemui.dagger.qualifiers.Main
 import com.android.systemui.flags.FeatureFlags
 import com.android.systemui.plugins.Clock
-import com.android.systemui.plugins.ClockDarkness
 import com.android.systemui.plugins.statusbar.StatusBarStateController
-import com.android.systemui.shared.navigationbar.RegionSamplingHelper
+import com.android.systemui.shared.regionsampling.RegionSamplingInstance
 import com.android.systemui.statusbar.policy.BatteryController
 import com.android.systemui.statusbar.policy.BatteryController.BatteryStateChangeCallback
 import com.android.systemui.statusbar.policy.ConfigurationController
@@ -44,7 +43,7 @@ import javax.inject.Inject
  * Controller for a Clock provided by the registry and used on the keyguard. Instantiated by
  * [KeyguardClockSwitchController]. Functionality is forked from [AnimatableClockController].
  */
-class ClockEventController @Inject constructor(
+open class ClockEventController @Inject constructor(
         private val statusBarStateController: StatusBarStateController,
         private val broadcastDispatcher: BroadcastDispatcher,
         private val batteryController: BatteryController,
@@ -61,6 +60,7 @@ class ClockEventController @Inject constructor(
             field = value
             if (value != null) {
                 value.initialize(resources, dozeAmount, 0f)
+                updateRegionSamplers(value)
             }
         }
 
@@ -71,94 +71,71 @@ class ClockEventController @Inject constructor(
     private var dozeAmount = 0f
     private var isKeyguardShowing = false
 
-    private var smallClockIsDark = ClockDarkness.DEFAULT
-    private var largeClockIsDark = ClockDarkness.DEFAULT
-    private var smallSamplingBounds = Rect()
-    private var largeSamplingBounds = Rect()
-
     private val regionSamplingEnabled =
             featureFlags.isEnabled(com.android.systemui.flags.Flags.REGION_SAMPLING)
 
-    private fun setClockDarkness(isRegionDark: Boolean): ClockDarkness {
-        return if (isRegionDark) {
-            ClockDarkness.DARK
-        } else {
-            ClockDarkness.LIGHT
+    private val updateFun = object : RegionSamplingInstance.UpdateColorCallback {
+        override fun updateColors() {
+            if (regionSamplingEnabled) {
+                smallClockIsDark = smallRegionSamplingInstance.currentRegionDarkness().isDark
+                largeClockIsDark = largeRegionSamplingInstance.currentRegionDarkness().isDark
+            } else {
+                val isLightTheme = TypedValue()
+                context.theme.resolveAttribute(android.R.attr.isLightTheme, isLightTheme, true)
+                smallClockIsDark = isLightTheme.data == 0
+                largeClockIsDark = isLightTheme.data == 0
+            }
+            clock?.events?.onColorPaletteChanged(resources, smallClockIsDark, largeClockIsDark)
         }
     }
 
-    // TODO: Abstract out the creation of RegionSampler and its fields
-    var smallRegionSampling: RegionSamplingHelper? =
-            if (!regionSamplingEnabled || clock == null) {
-                null
-            } else {
-                RegionSamplingHelper(clock?.smallClock,
-                        object : RegionSamplingHelper.SamplingCallback {
-                            override fun onRegionDarknessChanged(isRegionDark: Boolean) {
-                                smallClockIsDark = setClockDarkness(isRegionDark)
-                                clock?.events?.onColorPaletteChanged(
-                                        resources,
-                                        smallClockIsDark,
-                                        largeClockIsDark
-                                )
-                            }
+    fun updateRegionSamplers(currentClock: Clock?) {
+        smallRegionSamplingInstance = createRegionSampler(
+                currentClock?.smallClock,
+                mainExecutor,
+                bgExecutor,
+                regionSamplingEnabled,
+                updateFun
+        )
 
-                            override fun getSampledRegion(sampledView: View): Rect {
-                                smallSamplingBounds = Rect(
-                                        sampledView.left,
-                                        sampledView.top,
-                                        sampledView.right,
-                                        sampledView.bottom
-                                )
-                                return smallSamplingBounds
-                            }
+        largeRegionSamplingInstance = createRegionSampler(
+                currentClock?.largeClock,
+                mainExecutor,
+                bgExecutor,
+                regionSamplingEnabled,
+                updateFun
+        )
 
-                            override fun isSamplingEnabled(): Boolean {
-                                return regionSamplingEnabled
-                            }
-                        },
-                        mainExecutor, bgExecutor)
-            }
+        smallRegionSamplingInstance.startRegionSampler()
+        largeRegionSamplingInstance.startRegionSampler()
 
-    var largeRegionSampling: RegionSamplingHelper? =
-            if (!regionSamplingEnabled || clock == null) {
-                null
-            } else {
-                RegionSamplingHelper(clock?.largeClock,
-                        object : RegionSamplingHelper.SamplingCallback {
-                            override fun onRegionDarknessChanged(isRegionDark: Boolean) {
-                                largeClockIsDark = setClockDarkness(isRegionDark)
-                                clock?.events?.onColorPaletteChanged(
-                                        resources,
-                                        smallClockIsDark,
-                                        largeClockIsDark
-                                )
-                            }
+        updateFun.updateColors()
+    }
 
-                            override fun getSampledRegion(sampledView: View): Rect {
-                                largeSamplingBounds = Rect(
-                                        sampledView.left,
-                                        sampledView.top,
-                                        sampledView.right,
-                                        sampledView.bottom
-                                )
-                                return largeSamplingBounds
-                            }
+    protected open fun createRegionSampler(
+            sampledView: View?,
+            mainExecutor: Executor?,
+            bgExecutor: Executor?,
+            regionSamplingEnabled: Boolean,
+            updateFun: RegionSamplingInstance.UpdateColorCallback
+    ): RegionSamplingInstance {
+        return RegionSamplingInstance(
+            sampledView,
+            mainExecutor,
+            bgExecutor,
+            regionSamplingEnabled,
+            updateFun)
+    }
 
-                            override fun isSamplingEnabled(): Boolean {
-                                return regionSamplingEnabled
-                            }
-                        },
-                        mainExecutor, bgExecutor)
-            }
+    lateinit var smallRegionSamplingInstance: RegionSamplingInstance
+    lateinit var largeRegionSamplingInstance: RegionSamplingInstance
+
+    private var smallClockIsDark = true
+    private var largeClockIsDark = true
 
     private val configListener = object : ConfigurationController.ConfigurationListener {
         override fun onThemeChanged() {
-            clock?.events?.onColorPaletteChanged(
-                    resources,
-                    smallClockIsDark,
-                    largeClockIsDark
-            )
+            updateFun.updateColors()
         }
     }
 
@@ -209,9 +186,6 @@ class ClockEventController @Inject constructor(
 
     init {
         isDozing = statusBarStateController.isDozing
-        smallRegionSampling?.setWindowVisible(true)
-        largeRegionSampling?.setWindowVisible(true)
-        clock?.events?.onColorPaletteChanged(resources, smallClockIsDark, largeClockIsDark)
     }
 
     fun registerListeners() {
@@ -226,8 +200,8 @@ class ClockEventController @Inject constructor(
         batteryController.addCallback(batteryCallback)
         keyguardUpdateMonitor.registerCallback(keyguardUpdateMonitorCallback)
         statusBarStateController.addCallback(statusBarStateListener)
-        smallRegionSampling?.start(smallSamplingBounds)
-        largeRegionSampling?.start(largeSamplingBounds)
+        smallRegionSamplingInstance.startRegionSampler()
+        largeRegionSamplingInstance.startRegionSampler()
     }
 
     fun unregisterListeners() {
@@ -236,8 +210,8 @@ class ClockEventController @Inject constructor(
         batteryController.removeCallback(batteryCallback)
         keyguardUpdateMonitor.removeCallback(keyguardUpdateMonitorCallback)
         statusBarStateController.removeCallback(statusBarStateListener)
-        smallRegionSampling?.stop()
-        largeRegionSampling?.stop()
+        smallRegionSamplingInstance.stopRegionSampler()
+        largeRegionSamplingInstance.stopRegionSampler()
     }
 
     /**
@@ -246,8 +220,8 @@ class ClockEventController @Inject constructor(
     fun dump(pw: PrintWriter) {
         pw.println(this)
         clock?.dump(pw)
-        smallRegionSampling?.dump(pw)
-        largeRegionSampling?.dump(pw)
+        smallRegionSamplingInstance.dump(pw)
+        largeRegionSamplingInstance.dump(pw)
     }
 
     companion object {
diff --git a/packages/SystemUI/src/com/android/keyguard/KeyguardClockSwitch.java b/packages/SystemUI/src/com/android/keyguard/KeyguardClockSwitch.java
index 10d6d9fda548c..d7cd1d0dbc6f0 100644
--- a/packages/SystemUI/src/com/android/keyguard/KeyguardClockSwitch.java
+++ b/packages/SystemUI/src/com/android/keyguard/KeyguardClockSwitch.java
@@ -8,7 +8,6 @@ import android.content.Context;
 import android.util.AttributeSet;
 import android.util.Log;
 import android.view.View;
-import android.view.ViewGroup;
 import android.widget.FrameLayout;
 import android.widget.RelativeLayout;
 
@@ -106,9 +105,7 @@ public class KeyguardClockSwitch extends RelativeLayout {
         }
 
         // Attach small and big clock views to hierarchy.
-        mSmallClockFrame.addView(clock.getSmallClock(), -1,
-                new ViewGroup.LayoutParams(ViewGroup.LayoutParams.MATCH_PARENT,
-                        ViewGroup.LayoutParams.WRAP_CONTENT));
+        mSmallClockFrame.addView(clock.getSmallClock());
         mLargeClockFrame.addView(clock.getLargeClock());
     }
 
@@ -223,7 +220,7 @@ public class KeyguardClockSwitch extends RelativeLayout {
 
     public void dump(PrintWriter pw, String[] args) {
         pw.println("KeyguardClockSwitch:");
-        pw.println("  mClockFrame: " + mSmallClockFrame);
+        pw.println("  mSmallClockFrame: " + mSmallClockFrame);
         pw.println("  mLargeClockFrame: " + mLargeClockFrame);
         pw.println("  mStatusArea: " + mStatusArea);
         pw.println("  mDisplayedClockSize: " + mDisplayedClockSize);
diff --git a/packages/SystemUI/src/com/android/keyguard/KeyguardClockSwitchController.java b/packages/SystemUI/src/com/android/keyguard/KeyguardClockSwitchController.java
index dd78f1cef78ca..2165099b474e3 100644
--- a/packages/SystemUI/src/com/android/keyguard/KeyguardClockSwitchController.java
+++ b/packages/SystemUI/src/com/android/keyguard/KeyguardClockSwitchController.java
@@ -72,7 +72,6 @@ public class KeyguardClockSwitchController extends ViewController<KeyguardClockS
     private final DumpManager mDumpManager;
     private final ClockEventController mClockEventController;
 
-    /** Clock frames for both small and large sizes */
     private FrameLayout mSmallClockFrame; // top aligned clock
     private FrameLayout mLargeClockFrame; // centered clock
 
@@ -151,7 +150,7 @@ public class KeyguardClockSwitchController extends ViewController<KeyguardClockS
      * Attach the controller to the view it relates to.
      */
     @Override
-    public void onInit() {
+    protected void onInit() {
         mKeyguardSliceViewController.init();
 
         mSmallClockFrame = mView.findViewById(R.id.lockscreen_clock_view);
@@ -390,8 +389,6 @@ public class KeyguardClockSwitchController extends ViewController<KeyguardClockS
      * bounds during the unlock transition.
      */
     private void setClipChildrenForUnlock(boolean clip) {
-        mView.setClipChildren(clip);
-
         if (mStatusArea != null) {
             mStatusArea.setClipChildren(clip);
         }
diff --git a/packages/SystemUI/tests/src/com/android/keyguard/ClockEventControllerTest.kt b/packages/SystemUI/tests/src/com/android/keyguard/ClockEventControllerTest.kt
index 802194464b62c..914d94522e83f 100644
--- a/packages/SystemUI/tests/src/com/android/keyguard/ClockEventControllerTest.kt
+++ b/packages/SystemUI/tests/src/com/android/keyguard/ClockEventControllerTest.kt
@@ -107,13 +107,15 @@ class ClockEventControllerTest : SysuiTestCase() {
     @Test
     fun themeChanged_verifyClockPaletteUpdated() {
         clockEventController.clock = clock
+        verify(events).onColorPaletteChanged(any(), any(), any())
+
         clockEventController.registerListeners()
 
         val captor = argumentCaptor<ConfigurationController.ConfigurationListener>()
         verify(configurationController).addCallback(capture(captor))
         captor.value.onThemeChanged()
 
-        verify(events).onColorPaletteChanged(any(), any(), any())
+        verify(events, times(2)).onColorPaletteChanged(any(), any(), any())
     }
 
     @Test
@@ -257,6 +259,7 @@ class ClockEventControllerTest : SysuiTestCase() {
 
     @Test
     fun unregisterListeners_validate() {
+        clockEventController.clock = clock
         clockEventController.unregisterListeners()
         verify(broadcastDispatcher).unregisterReceiver(any())
         verify(configurationController).removeCallback(any())
diff --git a/packages/SystemUI/tests/src/com/android/systemui/shared/clocks/DefaultClockProviderTest.kt b/packages/SystemUI/tests/src/com/android/systemui/shared/clocks/DefaultClockProviderTest.kt
index 78694480ad5b6..2b4a109282ce1 100644
--- a/packages/SystemUI/tests/src/com/android/systemui/shared/clocks/DefaultClockProviderTest.kt
+++ b/packages/SystemUI/tests/src/com/android/systemui/shared/clocks/DefaultClockProviderTest.kt
@@ -19,17 +19,31 @@ package com.android.systemui.shared.clocks
 import android.content.res.Resources
 import android.graphics.drawable.Drawable
 import android.testing.AndroidTestingRunner
+import android.util.TypedValue
 import android.view.LayoutInflater
+import android.widget.FrameLayout
 import androidx.test.filters.SmallTest
 import com.android.systemui.R
 import com.android.systemui.SysuiTestCase
+import com.android.systemui.shared.clocks.DefaultClock.Companion.DOZE_COLOR
+import com.android.systemui.util.mockito.any
+import com.android.systemui.util.mockito.eq
+import com.android.systemui.util.mockito.mock
+import java.util.Locale
+import java.util.TimeZone
 import junit.framework.Assert.assertEquals
 import junit.framework.Assert.assertNotNull
 import org.junit.Before
 import org.junit.Rule
 import org.junit.Test
 import org.junit.runner.RunWith
+import org.mockito.ArgumentMatchers.anyBoolean
+import org.mockito.ArgumentMatchers.anyFloat
+import org.mockito.ArgumentMatchers.anyInt
+import org.mockito.ArgumentMatchers.notNull
 import org.mockito.Mock
+import org.mockito.Mockito.times
+import org.mockito.Mockito.verify
 import org.mockito.Mockito.`when` as whenever
 import org.mockito.junit.MockitoJUnit
 
@@ -39,7 +53,8 @@ class DefaultClockProviderTest : SysuiTestCase() {
 
     @JvmField @Rule val mockito = MockitoJUnit.rule()
 
-    @Mock private lateinit var mockClockView: AnimatableClockView
+    @Mock private lateinit var mockSmallClockView: AnimatableClockView
+    @Mock private lateinit var mockLargeClockView: AnimatableClockView
     @Mock private lateinit var layoutInflater: LayoutInflater
     @Mock private lateinit var mockClockThumbnail: Drawable
     @Mock private lateinit var resources: Resources
@@ -47,14 +62,16 @@ class DefaultClockProviderTest : SysuiTestCase() {
 
     @Before
     fun setUp() {
-        whenever(layoutInflater.inflate(R.layout.clock_default_small, null))
-            .thenReturn(mockClockView)
-        whenever(layoutInflater.inflate(R.layout.clock_default_large, null))
-            .thenReturn(mockClockView)
+        whenever(layoutInflater.inflate(eq(R.layout.clock_default_small), any(), anyBoolean()))
+            .thenReturn(mockSmallClockView)
+        whenever(layoutInflater.inflate(eq(R.layout.clock_default_large), any(), anyBoolean()))
+            .thenReturn(mockLargeClockView)
         whenever(resources.getDrawable(R.drawable.clock_default_thumbnail, null))
             .thenReturn(mockClockThumbnail)
+        whenever(mockSmallClockView.getLayoutParams()).thenReturn(FrameLayout.LayoutParams(10, 10))
+        whenever(mockLargeClockView.getLayoutParams()).thenReturn(FrameLayout.LayoutParams(10, 10))
 
-        provider = DefaultClockProvider(layoutInflater, resources)
+        provider = DefaultClockProvider(context, layoutInflater, resources)
     }
 
     @Test
@@ -71,7 +88,79 @@ class DefaultClockProviderTest : SysuiTestCase() {
         // Default clock provider must always provide the default clock
         val clock = provider.createClock(DEFAULT_CLOCK_ID)
         assertNotNull(clock)
-        assertEquals(clock.smallClock, mockClockView)
-        assertEquals(clock.largeClock, mockClockView)
+        assertEquals(clock.smallClock, mockSmallClockView)
+        assertEquals(clock.largeClock, mockLargeClockView)
+    }
+
+    @Test
+    fun defaultClock_initialize() {
+        val clock = provider.createClock(DEFAULT_CLOCK_ID)
+        clock.initialize(resources, 0f, 0f)
+
+        verify(mockSmallClockView, times(2)).setColors(eq(DOZE_COLOR), anyInt())
+        verify(mockLargeClockView, times(2)).setColors(eq(DOZE_COLOR), anyInt())
+        verify(mockSmallClockView).onTimeZoneChanged(notNull())
+        verify(mockLargeClockView).onTimeZoneChanged(notNull())
+        verify(mockSmallClockView).refreshTime()
+        verify(mockLargeClockView).refreshTime()
+        verify(mockLargeClockView).setLayoutParams(any())
+    }
+
+    @Test
+    fun defaultClock_events_onTimeTick() {
+        val clock = provider.createClock(DEFAULT_CLOCK_ID)
+        clock.events.onTimeTick()
+
+        verify(mockSmallClockView).refreshTime()
+        verify(mockLargeClockView).refreshTime()
+    }
+
+    @Test
+    fun defaultClock_events_onTimeFormatChanged() {
+        val clock = provider.createClock(DEFAULT_CLOCK_ID)
+        clock.events.onTimeFormatChanged(true)
+
+        verify(mockSmallClockView).refreshFormat(true)
+        verify(mockLargeClockView).refreshFormat(true)
+    }
+
+    @Test
+    fun defaultClock_events_onTimeZoneChanged() {
+        val timeZone = mock<TimeZone>()
+        val clock = provider.createClock(DEFAULT_CLOCK_ID)
+        clock.events.onTimeZoneChanged(timeZone)
+
+        verify(mockSmallClockView).onTimeZoneChanged(timeZone)
+        verify(mockLargeClockView).onTimeZoneChanged(timeZone)
+    }
+
+    @Test
+    fun defaultClock_events_onFontSettingChanged() {
+        val clock = provider.createClock(DEFAULT_CLOCK_ID)
+        clock.events.onFontSettingChanged()
+
+        verify(mockSmallClockView).setTextSize(eq(TypedValue.COMPLEX_UNIT_PX), anyFloat())
+        verify(mockLargeClockView).setTextSize(eq(TypedValue.COMPLEX_UNIT_PX), anyFloat())
+        verify(mockLargeClockView).setLayoutParams(any())
+    }
+
+    @Test
+    fun defaultClock_events_onColorPaletteChanged() {
+        val clock = provider.createClock(DEFAULT_CLOCK_ID)
+        clock.events.onColorPaletteChanged(resources, true, true)
+
+        verify(mockSmallClockView, times(2)).setColors(eq(DOZE_COLOR), anyInt())
+        verify(mockLargeClockView, times(2)).setColors(eq(DOZE_COLOR), anyInt())
+    }
+
+    @Test
+    fun defaultClock_events_onLocaleChanged() {
+        val clock = provider.createClock(DEFAULT_CLOCK_ID)
+        clock.events.onLocaleChanged(Locale.getDefault())
+
+        verify(mockSmallClockView, times(2)).setLineSpacingScale(anyFloat())
+        verify(mockLargeClockView, times(2)).setLineSpacingScale(anyFloat())
+        verify(mockSmallClockView, times(2)).refreshFormat()
+        verify(mockLargeClockView, times(2)).refreshFormat()
     }
 }