From 1b65e52344090a324e2f7472da25f5e5320ac235 Mon Sep 17 00:00:00 2001
From: Caitlin Shkuratov <caitlinshk@google.com>
Date: Mon, 31 Oct 2022 20:01:52 +0000
Subject: [PATCH] [Dock Defend] Add an optional shield to the status bar
 battery drawable.

The shield will be displayed when the battery is marked as overheated.

Bug: 255625888
Test: manual: issue `adb shell am broadcast -a com.android.systemui.demo
-e command battery -e overheated true` and verify the battery icon
displays a shield
Test: See bug for manual demo video
Test: statusbar.battery tests

Change-Id: I6b3036ae47ad7b5ae8dc78f83d019130935c9b50
---
 .../graph/ThemedBatteryDrawable.kt            |   7 +-
 packages/SystemUI/res/values/config.xml       |   6 +
 .../battery/AccessorizedBatteryDrawable.kt    | 202 ++++++++++++++++++
 .../systemui/battery/BatteryMeterView.java    |  44 +++-
 .../battery/BatteryMeterViewController.java   |   9 +
 .../android/systemui/battery/BatterySpecs.kt  | 109 ++++++++++
 .../src/com/android/systemui/flags/Flags.kt   |   3 +
 .../phone/dagger/StatusBarViewModule.java     |   2 +
 .../statusbar/policy/BatteryController.java   |   3 +
 .../policy/BatteryControllerImpl.java         |  30 +++
 .../AccessorizedBatteryDrawableTest.kt        |  52 +++++
 .../BatteryMeterViewControllerTest.java       |  50 ++++-
 .../systemui/battery/BatteryMeterViewTest.kt  |  42 +++-
 .../systemui/battery/BatterySpecsTest.kt      | 101 +++++++++
 .../policy/BatteryControllerTest.java         |  29 +++
 15 files changed, 669 insertions(+), 20 deletions(-)
 create mode 100644 packages/SystemUI/src/com/android/systemui/battery/AccessorizedBatteryDrawable.kt
 create mode 100644 packages/SystemUI/src/com/android/systemui/battery/BatterySpecs.kt
 create mode 100644 packages/SystemUI/tests/src/com/android/systemui/battery/AccessorizedBatteryDrawableTest.kt
 create mode 100644 packages/SystemUI/tests/src/com/android/systemui/battery/BatterySpecsTest.kt

diff --git a/packages/SettingsLib/src/com/android/settingslib/graph/ThemedBatteryDrawable.kt b/packages/SettingsLib/src/com/android/settingslib/graph/ThemedBatteryDrawable.kt
index 5fa04f93e993a..faea5b2c3e715 100644
--- a/packages/SettingsLib/src/com/android/settingslib/graph/ThemedBatteryDrawable.kt
+++ b/packages/SettingsLib/src/com/android/settingslib/graph/ThemedBatteryDrawable.kt
@@ -412,14 +412,13 @@ open class ThemedBatteryDrawable(private val context: Context, frameColor: Int)
     }
 
     companion object {
-        private const val TAG = "ThemedBatteryDrawable"
-        private const val WIDTH = 12f
-        private const val HEIGHT = 20f
+        const val WIDTH = 12f
+        const val HEIGHT = 20f
         private const val CRITICAL_LEVEL = 15
         // On a 12x20 grid, how wide to make the fill protection stroke.
         // Scales when our size changes
         private const val PROTECTION_STROKE_WIDTH = 3f
         // Arbitrarily chosen for visibility at small sizes
-        private const val PROTECTION_MIN_STROKE_WIDTH = 6f
+        const val PROTECTION_MIN_STROKE_WIDTH = 6f
     }
 }
diff --git a/packages/SystemUI/res/values/config.xml b/packages/SystemUI/res/values/config.xml
index ce9829b318cd7..55d637916d0cd 100644
--- a/packages/SystemUI/res/values/config.xml
+++ b/packages/SystemUI/res/values/config.xml
@@ -485,6 +485,12 @@
     <!-- Whether to show a severe low battery dialog. -->
     <bool name="config_severe_battery_dialog">false</bool>
 
+    <!-- A path representing a shield. Will sometimes be displayed with the battery icon when
+         needed. This path is a 10px wide and 13px tall. -->
+    <string name="config_batterymeterShieldPath" translatable="false">
+        M5 0L0 1.88V6.19C0 9.35 2.13 12.29 5 13.01C7.87 12.29 10 9.35 10 6.19V1.88L5 0Z
+    </string>
+
     <!-- A path similar to frameworks/base/core/res/res/values/config.xml
       config_mainBuiltInDisplayCutout that describes a path larger than the exact path of a display
       cutout. If present as well as config_enableDisplayCutoutProtection is set to true, then
diff --git a/packages/SystemUI/src/com/android/systemui/battery/AccessorizedBatteryDrawable.kt b/packages/SystemUI/src/com/android/systemui/battery/AccessorizedBatteryDrawable.kt
new file mode 100644
index 0000000000000..a91100a8856e4
--- /dev/null
+++ b/packages/SystemUI/src/com/android/systemui/battery/AccessorizedBatteryDrawable.kt
@@ -0,0 +1,202 @@
+/*
+ * Copyright (C) 2022 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file
+ * except in compliance with the License. You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software distributed under the
+ * License is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+ * KIND, either express or implied. See the License for the specific language governing
+ * permissions and limitations under the License.
+ */
+
+package com.android.systemui.battery
+
+import android.content.Context
+import android.graphics.Canvas
+import android.graphics.Color
+import android.graphics.ColorFilter
+import android.graphics.Matrix
+import android.graphics.Paint
+import android.graphics.Path
+import android.graphics.PixelFormat
+import android.graphics.PorterDuff
+import android.graphics.PorterDuffXfermode
+import android.graphics.Rect
+import android.graphics.drawable.DrawableWrapper
+import android.util.PathParser
+import com.android.settingslib.graph.ThemedBatteryDrawable
+import com.android.systemui.R
+import com.android.systemui.battery.BatterySpecs.BATTERY_HEIGHT
+import com.android.systemui.battery.BatterySpecs.BATTERY_HEIGHT_WITH_SHIELD
+import com.android.systemui.battery.BatterySpecs.BATTERY_WIDTH
+import com.android.systemui.battery.BatterySpecs.BATTERY_WIDTH_WITH_SHIELD
+import com.android.systemui.battery.BatterySpecs.SHIELD_LEFT_OFFSET
+import com.android.systemui.battery.BatterySpecs.SHIELD_STROKE
+import com.android.systemui.battery.BatterySpecs.SHIELD_TOP_OFFSET
+
+/**
+ * A battery drawable that accessorizes [ThemedBatteryDrawable] with additional information if
+ * necessary.
+ *
+ * For now, it adds a shield in the bottom-right corner when [displayShield] is true.
+ */
+class AccessorizedBatteryDrawable(
+    private val context: Context,
+    frameColor: Int,
+) : DrawableWrapper(ThemedBatteryDrawable(context, frameColor)) {
+    private val mainBatteryDrawable: ThemedBatteryDrawable
+        get() = drawable as ThemedBatteryDrawable
+
+    private val shieldPath = Path()
+    private val scaledShield = Path()
+    private val scaleMatrix = Matrix()
+
+    private var shieldLeftOffsetScaled = SHIELD_LEFT_OFFSET
+    private var shieldTopOffsetScaled = SHIELD_TOP_OFFSET
+
+    private val dualTone =
+        context.resources.getBoolean(com.android.internal.R.bool.config_batterymeterDualTone)
+
+    private val shieldTransparentOutlinePaint =
+        Paint(Paint.ANTI_ALIAS_FLAG).also { p ->
+            p.color = Color.TRANSPARENT
+            p.strokeWidth = ThemedBatteryDrawable.PROTECTION_MIN_STROKE_WIDTH
+            p.xfermode = PorterDuffXfermode(PorterDuff.Mode.SRC_IN)
+            p.style = Paint.Style.FILL_AND_STROKE
+        }
+
+    private val shieldPaint =
+        Paint(Paint.ANTI_ALIAS_FLAG).also { p ->
+            p.color = Color.MAGENTA
+            p.style = Paint.Style.FILL
+            p.isDither = true
+        }
+
+    init {
+        loadPaths()
+    }
+
+    override fun onBoundsChange(bounds: Rect) {
+        super.onBoundsChange(bounds)
+        updateSizes()
+    }
+
+    var displayShield: Boolean = false
+
+    private fun updateSizes() {
+        val b = bounds
+        if (b.isEmpty) {
+            return
+        }
+
+        val mainWidth = BatterySpecs.getMainBatteryWidth(b.width().toFloat(), displayShield)
+        val mainHeight = BatterySpecs.getMainBatteryHeight(b.height().toFloat(), displayShield)
+
+        drawable?.setBounds(
+            b.left,
+            b.top,
+            /* right= */ b.left + mainWidth.toInt(),
+            /* bottom= */ b.top + mainHeight.toInt()
+        )
+
+        if (displayShield) {
+            val sx = b.right / BATTERY_WIDTH_WITH_SHIELD
+            val sy = b.bottom / BATTERY_HEIGHT_WITH_SHIELD
+            scaleMatrix.setScale(sx, sy)
+            shieldPath.transform(scaleMatrix, scaledShield)
+
+            shieldLeftOffsetScaled = sx * SHIELD_LEFT_OFFSET
+            shieldTopOffsetScaled = sy * SHIELD_TOP_OFFSET
+
+            val scaledStrokeWidth =
+                (sx * SHIELD_STROKE).coerceAtLeast(
+                    ThemedBatteryDrawable.PROTECTION_MIN_STROKE_WIDTH
+                )
+            shieldTransparentOutlinePaint.strokeWidth = scaledStrokeWidth
+        }
+    }
+
+    override fun getIntrinsicHeight(): Int {
+        val height =
+            if (displayShield) {
+                BATTERY_HEIGHT_WITH_SHIELD
+            } else {
+                BATTERY_HEIGHT
+            }
+        // TODO(b/255625888): Cache the density so we don't have to re-fetch.
+        return (height * context.resources.displayMetrics.density).toInt()
+    }
+
+    override fun getIntrinsicWidth(): Int {
+        val width =
+            if (displayShield) {
+                BATTERY_WIDTH_WITH_SHIELD
+            } else {
+                BATTERY_WIDTH
+            }
+        // TODO(b/255625888): Cache the density so we don't have to re-fetch.
+        return (width * context.resources.displayMetrics.density).toInt()
+    }
+
+    override fun draw(c: Canvas) {
+        c.saveLayer(null, null)
+        // Draw the main battery icon
+        super.draw(c)
+
+        if (displayShield) {
+            c.translate(shieldLeftOffsetScaled, shieldTopOffsetScaled)
+            // We need a transparent outline around the shield, so first draw the transparent-ness
+            // then draw the shield
+            c.drawPath(scaledShield, shieldTransparentOutlinePaint)
+            c.drawPath(scaledShield, shieldPaint)
+        }
+        c.restore()
+    }
+
+    override fun getOpacity(): Int {
+        return PixelFormat.OPAQUE
+    }
+
+    override fun setAlpha(p0: Int) {
+        // Unused internally -- see [ThemedBatteryDrawable.setAlpha].
+    }
+
+    override fun setColorFilter(colorfilter: ColorFilter?) {
+        super.setColorFilter(colorFilter)
+        shieldPaint.colorFilter = colorFilter
+    }
+
+    /** Sets whether the battery is currently charging. */
+    fun setCharging(charging: Boolean) {
+        mainBatteryDrawable.charging = charging
+    }
+
+    /** Sets the current level (out of 100) of the battery. */
+    fun setBatteryLevel(level: Int) {
+        mainBatteryDrawable.setBatteryLevel(level)
+    }
+
+    /** Sets whether power save is enabled. */
+    fun setPowerSaveEnabled(powerSaveEnabled: Boolean) {
+        mainBatteryDrawable.powerSaveEnabled = powerSaveEnabled
+    }
+
+    /** Returns whether power save is currently enabled. */
+    fun getPowerSaveEnabled(): Boolean {
+        return mainBatteryDrawable.powerSaveEnabled
+    }
+
+    /** Sets the colors to use for the icon. */
+    fun setColors(fgColor: Int, bgColor: Int, singleToneColor: Int) {
+        shieldPaint.color = if (dualTone) fgColor else singleToneColor
+        mainBatteryDrawable.setColors(fgColor, bgColor, singleToneColor)
+    }
+
+    private fun loadPaths() {
+        val shieldPathString = context.resources.getString(R.string.config_batterymeterShieldPath)
+        shieldPath.set(PathParser.createPathFromPathData(shieldPathString))
+    }
+}
diff --git a/packages/SystemUI/src/com/android/systemui/battery/BatteryMeterView.java b/packages/SystemUI/src/com/android/systemui/battery/BatteryMeterView.java
index 6a10d4ab1e8b0..d301858505b9f 100644
--- a/packages/SystemUI/src/com/android/systemui/battery/BatteryMeterView.java
+++ b/packages/SystemUI/src/com/android/systemui/battery/BatteryMeterView.java
@@ -45,7 +45,6 @@ import android.widget.TextView;
 import androidx.annotation.StyleRes;
 import androidx.annotation.VisibleForTesting;
 
-import com.android.settingslib.graph.ThemedBatteryDrawable;
 import com.android.systemui.DualToneHandler;
 import com.android.systemui.R;
 import com.android.systemui.animation.Interpolators;
@@ -68,7 +67,7 @@ public class BatteryMeterView extends LinearLayout implements DarkReceiver {
     public static final int MODE_OFF = 2;
     public static final int MODE_ESTIMATE = 3;
 
-    private final ThemedBatteryDrawable mDrawable;
+    private final AccessorizedBatteryDrawable mDrawable;
     private final ImageView mBatteryIconView;
     private TextView mBatteryPercentView;
 
@@ -78,6 +77,8 @@ public class BatteryMeterView extends LinearLayout implements DarkReceiver {
     private int mShowPercentMode = MODE_DEFAULT;
     private boolean mShowPercentAvailable;
     private boolean mCharging;
+    private boolean mDisplayShield;
+    private boolean mDisplayShieldEnabled;
     // Error state where we know nothing about the current battery state
     private boolean mBatteryStateUnknown;
     // Lazily-loaded since this is expected to be a rare-if-ever state
@@ -106,7 +107,7 @@ public class BatteryMeterView extends LinearLayout implements DarkReceiver {
         final int frameColor = atts.getColor(R.styleable.BatteryMeterView_frameColor,
                 context.getColor(R.color.meter_background_color));
         mPercentageStyleId = atts.getResourceId(R.styleable.BatteryMeterView_textAppearance, 0);
-        mDrawable = new ThemedBatteryDrawable(context, frameColor);
+        mDrawable = new AccessorizedBatteryDrawable(context, frameColor);
         atts.recycle();
 
         mShowPercentAvailable = context.getResources().getBoolean(
@@ -203,6 +204,19 @@ public class BatteryMeterView extends LinearLayout implements DarkReceiver {
         mDrawable.setPowerSaveEnabled(isPowerSave);
     }
 
+    void onIsOverheatedChanged(boolean isOverheated) {
+        // The battery drawable is a different size depending on whether it's currently overheated
+        // or not, so we need to re-scale the view when overheated changes.
+        boolean requiresScaling = mDisplayShield != isOverheated;
+        // If the battery is marked as overheated, we should display a shield indicating that the
+        // battery is being "defended".
+        mDisplayShield = isOverheated;
+        if (requiresScaling) {
+            scaleBatteryMeterViews();
+        }
+        // TODO(b/255625888): We should also update the content description.
+    }
+
     private TextView loadPercentView() {
         return (TextView) LayoutInflater.from(getContext())
                 .inflate(R.layout.battery_percentage_view, null);
@@ -227,6 +241,10 @@ public class BatteryMeterView extends LinearLayout implements DarkReceiver {
         mBatteryEstimateFetcher = fetcher;
     }
 
+    void setDisplayShieldEnabled(boolean displayShieldEnabled) {
+        mDisplayShieldEnabled = displayShieldEnabled;
+    }
+
     void updatePercentText() {
         if (mBatteryStateUnknown) {
             setContentDescription(getContext().getString(R.string.accessibility_battery_unknown));
@@ -349,15 +367,29 @@ public class BatteryMeterView extends LinearLayout implements DarkReceiver {
         res.getValue(R.dimen.status_bar_icon_scale_factor, typedValue, true);
         float iconScaleFactor = typedValue.getFloat();
 
-        int batteryHeight = res.getDimensionPixelSize(R.dimen.status_bar_battery_icon_height);
-        int batteryWidth = res.getDimensionPixelSize(R.dimen.status_bar_battery_icon_width);
+        float mainBatteryHeight =
+                res.getDimensionPixelSize(R.dimen.status_bar_battery_icon_height) * iconScaleFactor;
+        float mainBatteryWidth =
+                res.getDimensionPixelSize(R.dimen.status_bar_battery_icon_width) * iconScaleFactor;
+
+        boolean displayShield = mDisplayShieldEnabled && mDisplayShield;
+        float fullBatteryIconHeight =
+                BatterySpecs.getFullBatteryHeight(mainBatteryHeight, displayShield);
+        float fullBatteryIconWidth =
+                BatterySpecs.getFullBatteryWidth(mainBatteryWidth, displayShield);
+
+        // TODO(b/255625888): Add some marginTop so that, even when the battery icon has the shield,
+        //   the bottom of the main icon is still aligned with the bottom of all the other icons.
         int marginBottom = res.getDimensionPixelSize(R.dimen.battery_margin_bottom);
 
         LinearLayout.LayoutParams scaledLayoutParams = new LinearLayout.LayoutParams(
-                (int) (batteryWidth * iconScaleFactor), (int) (batteryHeight * iconScaleFactor));
+                Math.round(fullBatteryIconWidth),
+                Math.round(fullBatteryIconHeight));
         scaledLayoutParams.setMargins(0, 0, 0, marginBottom);
 
+        mDrawable.setDisplayShield(displayShield);
         mBatteryIconView.setLayoutParams(scaledLayoutParams);
+        mBatteryIconView.invalidateDrawable(mDrawable);
     }
 
     @Override
diff --git a/packages/SystemUI/src/com/android/systemui/battery/BatteryMeterViewController.java b/packages/SystemUI/src/com/android/systemui/battery/BatteryMeterViewController.java
index ae9a32309d45c..77cb9d1bf594a 100644
--- a/packages/SystemUI/src/com/android/systemui/battery/BatteryMeterViewController.java
+++ b/packages/SystemUI/src/com/android/systemui/battery/BatteryMeterViewController.java
@@ -29,6 +29,8 @@ import android.view.View;
 
 import com.android.systemui.broadcast.BroadcastDispatcher;
 import com.android.systemui.dagger.qualifiers.Main;
+import com.android.systemui.flags.FeatureFlags;
+import com.android.systemui.flags.Flags;
 import com.android.systemui.settings.CurrentUserTracker;
 import com.android.systemui.statusbar.phone.StatusBarIconController;
 import com.android.systemui.statusbar.policy.BatteryController;
@@ -84,6 +86,11 @@ public class BatteryMeterViewController extends ViewController<BatteryMeterView>
                 public void onBatteryUnknownStateChanged(boolean isUnknown) {
                     mView.onBatteryUnknownStateChanged(isUnknown);
                 }
+
+                @Override
+                public void onIsOverheatedChanged(boolean isOverheated) {
+                    mView.onIsOverheatedChanged(isOverheated);
+                }
             };
 
     // Some places may need to show the battery conditionally, and not obey the tuner
@@ -98,6 +105,7 @@ public class BatteryMeterViewController extends ViewController<BatteryMeterView>
             BroadcastDispatcher broadcastDispatcher,
             @Main Handler mainHandler,
             ContentResolver contentResolver,
+            FeatureFlags featureFlags,
             BatteryController batteryController) {
         super(view);
         mConfigurationController = configurationController;
@@ -106,6 +114,7 @@ public class BatteryMeterViewController extends ViewController<BatteryMeterView>
         mBatteryController = batteryController;
 
         mView.setBatteryEstimateFetcher(mBatteryController::getEstimatedTimeRemainingString);
+        mView.setDisplayShieldEnabled(featureFlags.isEnabled(Flags.BATTERY_SHIELD_ICON));
 
         mSlotBattery = getResources().getString(com.android.internal.R.string.status_bar_battery);
         mSettingObserver = new SettingObserver(mainHandler);
diff --git a/packages/SystemUI/src/com/android/systemui/battery/BatterySpecs.kt b/packages/SystemUI/src/com/android/systemui/battery/BatterySpecs.kt
new file mode 100644
index 0000000000000..6455a9656fdee
--- /dev/null
+++ b/packages/SystemUI/src/com/android/systemui/battery/BatterySpecs.kt
@@ -0,0 +1,109 @@
+/*
+ * Copyright (C) 2022 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file
+ * except in compliance with the License. You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software distributed under the
+ * License is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+ * KIND, either express or implied. See the License for the specific language governing
+ * permissions and limitations under the License.
+ */
+
+package com.android.systemui.battery
+
+import com.android.settingslib.graph.ThemedBatteryDrawable
+
+/** An object storing specs related to the battery icon in the status bar. */
+object BatterySpecs {
+
+    /** Width of the main battery icon, not including the shield. */
+    const val BATTERY_WIDTH = ThemedBatteryDrawable.WIDTH
+    /** Height of the main battery icon, not including the shield. */
+    const val BATTERY_HEIGHT = ThemedBatteryDrawable.HEIGHT
+
+    private const val SHIELD_WIDTH = 10f
+    private const val SHIELD_HEIGHT = 13f
+
+    /**
+     * Amount that the left side of the shield should be offset from the left side of the battery.
+     */
+    const val SHIELD_LEFT_OFFSET = 8f
+    /** Amount that the top of the shield should be offset from the top of the battery. */
+    const val SHIELD_TOP_OFFSET = 10f
+
+    const val SHIELD_STROKE = 4f
+
+    /** The full width of the battery icon, including the main battery icon *and* the shield. */
+    const val BATTERY_WIDTH_WITH_SHIELD = SHIELD_LEFT_OFFSET + SHIELD_WIDTH
+    /** The full height of the battery icon, including the main battery icon *and* the shield. */
+    const val BATTERY_HEIGHT_WITH_SHIELD = SHIELD_TOP_OFFSET + SHIELD_HEIGHT
+
+    /**
+     * Given the desired height of the main battery icon in pixels, returns the height that the full
+     * battery icon will take up in pixels.
+     *
+     * If there's no shield, this will just return [mainBatteryHeight]. Otherwise, the shield
+     * extends slightly below the bottom of the main battery icon so we need some extra height.
+     */
+    @JvmStatic
+    fun getFullBatteryHeight(mainBatteryHeight: Float, displayShield: Boolean): Float {
+        return if (!displayShield) {
+            mainBatteryHeight
+        } else {
+            val verticalScaleFactor = mainBatteryHeight / BATTERY_HEIGHT
+            verticalScaleFactor * BATTERY_HEIGHT_WITH_SHIELD
+        }
+    }
+
+    /**
+     * Given the desired width of the main battery icon in pixels, returns the width that the full
+     * battery icon will take up in pixels.
+     *
+     * If there's no shield, this will just return [mainBatteryWidth]. Otherwise, the shield extends
+     * past the right side of the main battery icon so we need some extra width.
+     */
+    @JvmStatic
+    fun getFullBatteryWidth(mainBatteryWidth: Float, displayShield: Boolean): Float {
+        return if (!displayShield) {
+            mainBatteryWidth
+        } else {
+            val horizontalScaleFactor = mainBatteryWidth / BATTERY_WIDTH
+            horizontalScaleFactor * BATTERY_WIDTH_WITH_SHIELD
+        }
+    }
+
+    /**
+     * Given the height of the full battery icon, return how tall the main battery icon should be.
+     *
+     * If there's no shield, this will just return [fullBatteryHeight]. Otherwise, the shield takes
+     * up some of the view's height so the main battery width will be just a portion of
+     * [fullBatteryHeight].
+     */
+    @JvmStatic
+    fun getMainBatteryHeight(fullBatteryHeight: Float, displayShield: Boolean): Float {
+        return if (!displayShield) {
+            fullBatteryHeight
+        } else {
+            return (BATTERY_HEIGHT / BATTERY_HEIGHT_WITH_SHIELD) * fullBatteryHeight
+        }
+    }
+
+    /**
+     * Given the width of the full battery icon, return how wide the main battery icon should be.
+     *
+     * If there's no shield, this will just return [fullBatteryWidth]. Otherwise, the shield takes
+     * up some of the view's width so the main battery width will be just a portion of
+     * [fullBatteryWidth].
+     */
+    @JvmStatic
+    fun getMainBatteryWidth(fullBatteryWidth: Float, displayShield: Boolean): Float {
+        return if (!displayShield) {
+            fullBatteryWidth
+        } else {
+            return (BATTERY_WIDTH / BATTERY_WIDTH_WITH_SHIELD) * fullBatteryWidth
+        }
+    }
+}
diff --git a/packages/SystemUI/src/com/android/systemui/flags/Flags.kt b/packages/SystemUI/src/com/android/systemui/flags/Flags.kt
index 99dfefa4fa417..f34749f9d8926 100644
--- a/packages/SystemUI/src/com/android/systemui/flags/Flags.kt
+++ b/packages/SystemUI/src/com/android/systemui/flags/Flags.kt
@@ -233,6 +233,9 @@ object Flags {
     // TODO(b/256613548): Tracking Bug
     val NEW_STATUS_BAR_WIFI_ICON_BACKEND = unreleasedFlag(609, "new_status_bar_wifi_icon_backend")
 
+    // TODO(b/256623670): Tracking Bug
+    @JvmField val BATTERY_SHIELD_ICON = unreleasedFlag(610, "battery_shield_icon")
+
     // 700 - dialer/calls
     // TODO(b/254512734): Tracking Bug
     val ONGOING_CALL_STATUS_BAR_CHIP = releasedFlag(700, "ongoing_call_status_bar_chip")
diff --git a/packages/SystemUI/src/com/android/systemui/statusbar/phone/dagger/StatusBarViewModule.java b/packages/SystemUI/src/com/android/systemui/statusbar/phone/dagger/StatusBarViewModule.java
index dc902666874d0..615f2304ecf98 100644
--- a/packages/SystemUI/src/com/android/systemui/statusbar/phone/dagger/StatusBarViewModule.java
+++ b/packages/SystemUI/src/com/android/systemui/statusbar/phone/dagger/StatusBarViewModule.java
@@ -226,6 +226,7 @@ public abstract class StatusBarViewModule {
             BroadcastDispatcher broadcastDispatcher,
             @Main Handler mainHandler,
             ContentResolver contentResolver,
+            FeatureFlags featureFlags,
             BatteryController batteryController
     ) {
         return new BatteryMeterViewController(
@@ -235,6 +236,7 @@ public abstract class StatusBarViewModule {
                 broadcastDispatcher,
                 mainHandler,
                 contentResolver,
+                featureFlags,
                 batteryController);
 
     }
diff --git a/packages/SystemUI/src/com/android/systemui/statusbar/policy/BatteryController.java b/packages/SystemUI/src/com/android/systemui/statusbar/policy/BatteryController.java
index 149ed0a71b919..d10d7cf8460bb 100644
--- a/packages/SystemUI/src/com/android/systemui/statusbar/policy/BatteryController.java
+++ b/packages/SystemUI/src/com/android/systemui/statusbar/policy/BatteryController.java
@@ -155,6 +155,9 @@ public interface BatteryController extends DemoMode,
 
         default void onWirelessChargingChanged(boolean isWirlessCharging) {
         }
+
+        default void onIsOverheatedChanged(boolean isOverheated) {
+        }
     }
 
     /**
diff --git a/packages/SystemUI/src/com/android/systemui/statusbar/policy/BatteryControllerImpl.java b/packages/SystemUI/src/com/android/systemui/statusbar/policy/BatteryControllerImpl.java
index c7ad767229294..3c2ac7b7a1243 100644
--- a/packages/SystemUI/src/com/android/systemui/statusbar/policy/BatteryControllerImpl.java
+++ b/packages/SystemUI/src/com/android/systemui/statusbar/policy/BatteryControllerImpl.java
@@ -16,6 +16,9 @@
 
 package com.android.systemui.statusbar.policy;
 
+import static android.os.BatteryManager.BATTERY_HEALTH_OVERHEAT;
+import static android.os.BatteryManager.BATTERY_HEALTH_UNKNOWN;
+import static android.os.BatteryManager.EXTRA_HEALTH;
 import static android.os.BatteryManager.EXTRA_PRESENT;
 
 import android.annotation.WorkerThread;
@@ -87,6 +90,7 @@ public class BatteryControllerImpl extends BroadcastReceiver implements BatteryC
     protected boolean mPowerSave;
     private boolean mAodPowerSave;
     private boolean mWirelessCharging;
+    private boolean mIsOverheated = false;
     private boolean mTestMode = false;
     @VisibleForTesting
     boolean mHasReceivedBattery = false;
@@ -184,6 +188,7 @@ public class BatteryControllerImpl extends BroadcastReceiver implements BatteryC
         cb.onPowerSaveChanged(mPowerSave);
         cb.onBatteryUnknownStateChanged(mStateUnknown);
         cb.onWirelessChargingChanged(mWirelessCharging);
+        cb.onIsOverheatedChanged(mIsOverheated);
     }
 
     @Override
@@ -222,6 +227,13 @@ public class BatteryControllerImpl extends BroadcastReceiver implements BatteryC
                 fireBatteryUnknownStateChanged();
             }
 
+            int batteryHealth = intent.getIntExtra(EXTRA_HEALTH, BATTERY_HEALTH_UNKNOWN);
+            boolean isOverheated = batteryHealth == BATTERY_HEALTH_OVERHEAT;
+            if (isOverheated != mIsOverheated) {
+                mIsOverheated = isOverheated;
+                fireIsOverheatedChanged();
+            }
+
             fireBatteryLevelChanged();
         } else if (action.equals(PowerManager.ACTION_POWER_SAVE_MODE_CHANGED)) {
             updatePowerSave();
@@ -292,6 +304,10 @@ public class BatteryControllerImpl extends BroadcastReceiver implements BatteryC
         return mPluggedChargingSource == BatteryManager.BATTERY_PLUGGED_WIRELESS;
     }
 
+    public boolean isOverheated() {
+        return mIsOverheated;
+    }
+
     @Override
     public void getEstimatedTimeRemainingString(EstimateFetchCompletion completion) {
         // Need to fetch or refresh the estimate, but it may involve binder calls so offload the
@@ -402,6 +418,15 @@ public class BatteryControllerImpl extends BroadcastReceiver implements BatteryC
         }
     }
 
+    private void fireIsOverheatedChanged() {
+        synchronized (mChangeCallbacks) {
+            final int n = mChangeCallbacks.size();
+            for (int i = 0; i < n; i++) {
+                mChangeCallbacks.get(i).onIsOverheatedChanged(mIsOverheated);
+            }
+        }
+    }
+
     @Override
     public void dispatchDemoCommand(String command, Bundle args) {
         if (!mDemoModeController.isInDemoMode()) {
@@ -412,6 +437,7 @@ public class BatteryControllerImpl extends BroadcastReceiver implements BatteryC
         String plugged = args.getString("plugged");
         String powerSave = args.getString("powersave");
         String present = args.getString("present");
+        String overheated = args.getString("overheated");
         if (level != null) {
             mLevel = Math.min(Math.max(Integer.parseInt(level), 0), 100);
         }
@@ -426,6 +452,10 @@ public class BatteryControllerImpl extends BroadcastReceiver implements BatteryC
             mStateUnknown = !present.equals("true");
             fireBatteryUnknownStateChanged();
         }
+        if (overheated != null) {
+            mIsOverheated = overheated.equals("true");
+            fireIsOverheatedChanged();
+        }
         fireBatteryLevelChanged();
     }
 
diff --git a/packages/SystemUI/tests/src/com/android/systemui/battery/AccessorizedBatteryDrawableTest.kt b/packages/SystemUI/tests/src/com/android/systemui/battery/AccessorizedBatteryDrawableTest.kt
new file mode 100644
index 0000000000000..982f033d05e5a
--- /dev/null
+++ b/packages/SystemUI/tests/src/com/android/systemui/battery/AccessorizedBatteryDrawableTest.kt
@@ -0,0 +1,52 @@
+/*
+ * Copyright (C) 2022 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.android.systemui.battery
+
+import androidx.test.filters.SmallTest
+import com.android.systemui.SysuiTestCase
+import com.android.systemui.battery.BatterySpecs.BATTERY_HEIGHT
+import com.android.systemui.battery.BatterySpecs.BATTERY_HEIGHT_WITH_SHIELD
+import com.android.systemui.battery.BatterySpecs.BATTERY_WIDTH
+import com.android.systemui.battery.BatterySpecs.BATTERY_WIDTH_WITH_SHIELD
+import com.google.common.truth.Truth.assertThat
+import org.junit.Test
+
+@SmallTest
+class AccessorizedBatteryDrawableTest : SysuiTestCase() {
+    @Test
+    fun intrinsicSize_shieldFalse_isBatterySize() {
+        val drawable = AccessorizedBatteryDrawable(context, frameColor = 0)
+        drawable.displayShield = false
+
+        val density = context.resources.displayMetrics.density
+        assertThat(drawable.intrinsicHeight).isEqualTo((BATTERY_HEIGHT * density).toInt())
+        assertThat(drawable.intrinsicWidth).isEqualTo((BATTERY_WIDTH * density).toInt())
+    }
+
+    @Test
+    fun intrinsicSize_shieldTrue_isBatteryPlusShieldSize() {
+        val drawable = AccessorizedBatteryDrawable(context, frameColor = 0)
+        drawable.displayShield = true
+
+        val density = context.resources.displayMetrics.density
+        assertThat(drawable.intrinsicHeight)
+            .isEqualTo((BATTERY_HEIGHT_WITH_SHIELD * density).toInt())
+        assertThat(drawable.intrinsicWidth).isEqualTo((BATTERY_WIDTH_WITH_SHIELD * density).toInt())
+    }
+
+    // TODO(b/255625888): Screenshot tests for this drawable would be amazing!
+}
diff --git a/packages/SystemUI/tests/src/com/android/systemui/battery/BatteryMeterViewControllerTest.java b/packages/SystemUI/tests/src/com/android/systemui/battery/BatteryMeterViewControllerTest.java
index 1d038a43ec8e2..bc8f96198b275 100644
--- a/packages/SystemUI/tests/src/com/android/systemui/battery/BatteryMeterViewControllerTest.java
+++ b/packages/SystemUI/tests/src/com/android/systemui/battery/BatteryMeterViewControllerTest.java
@@ -35,6 +35,8 @@ import androidx.test.filters.SmallTest;
 
 import com.android.systemui.SysuiTestCase;
 import com.android.systemui.broadcast.BroadcastDispatcher;
+import com.android.systemui.flags.FakeFeatureFlags;
+import com.android.systemui.flags.Flags;
 import com.android.systemui.statusbar.policy.BatteryController;
 import com.android.systemui.statusbar.policy.ConfigurationController;
 import com.android.systemui.tuner.TunerService;
@@ -59,6 +61,7 @@ public class BatteryMeterViewControllerTest extends SysuiTestCase {
     private Handler mHandler;
     @Mock
     private ContentResolver mContentResolver;
+    private FakeFeatureFlags mFeatureFlags;
     @Mock
     private BatteryController mBatteryController;
 
@@ -71,19 +74,13 @@ public class BatteryMeterViewControllerTest extends SysuiTestCase {
         when(mBatteryMeterView.getContext()).thenReturn(mContext);
         when(mBatteryMeterView.getResources()).thenReturn(mContext.getResources());
 
-        mController = new BatteryMeterViewController(
-                mBatteryMeterView,
-                mConfigurationController,
-                mTunerService,
-                mBroadcastDispatcher,
-                mHandler,
-                mContentResolver,
-                mBatteryController
-        );
+        mFeatureFlags = new FakeFeatureFlags();
+        mFeatureFlags.set(Flags.BATTERY_SHIELD_ICON, false);
     }
 
     @Test
     public void onViewAttached_callbacksRegistered() {
+        initController();
         mController.onViewAttached();
 
         verify(mConfigurationController).addCallback(any());
@@ -101,6 +98,7 @@ public class BatteryMeterViewControllerTest extends SysuiTestCase {
 
     @Test
     public void onViewDetached_callbacksUnregistered() {
+        initController();
         // Set everything up first.
         mController.onViewAttached();
 
@@ -114,6 +112,7 @@ public class BatteryMeterViewControllerTest extends SysuiTestCase {
 
     @Test
     public void ignoreTunerUpdates_afterOnViewAttached_callbackUnregistered() {
+        initController();
         // Start out receiving tuner updates
         mController.onViewAttached();
 
@@ -124,10 +123,43 @@ public class BatteryMeterViewControllerTest extends SysuiTestCase {
 
     @Test
     public void ignoreTunerUpdates_beforeOnViewAttached_callbackNeverRegistered() {
+        initController();
+
         mController.ignoreTunerUpdates();
 
         mController.onViewAttached();
 
         verify(mTunerService, never()).addTunable(any(), any());
     }
+
+    @Test
+    public void shieldFlagDisabled_viewNotified() {
+        mFeatureFlags.set(Flags.BATTERY_SHIELD_ICON, false);
+
+        initController();
+
+        verify(mBatteryMeterView).setDisplayShieldEnabled(false);
+    }
+
+    @Test
+    public void shieldFlagEnabled_viewNotified() {
+        mFeatureFlags.set(Flags.BATTERY_SHIELD_ICON, true);
+
+        initController();
+
+        verify(mBatteryMeterView).setDisplayShieldEnabled(true);
+    }
+
+    private void initController() {
+        mController = new BatteryMeterViewController(
+                mBatteryMeterView,
+                mConfigurationController,
+                mTunerService,
+                mBroadcastDispatcher,
+                mHandler,
+                mContentResolver,
+                mFeatureFlags,
+                mBatteryController
+        );
+    }
 }
diff --git a/packages/SystemUI/tests/src/com/android/systemui/battery/BatteryMeterViewTest.kt b/packages/SystemUI/tests/src/com/android/systemui/battery/BatteryMeterViewTest.kt
index b4ff2a5e1fbf0..851b5408a4e00 100644
--- a/packages/SystemUI/tests/src/com/android/systemui/battery/BatteryMeterViewTest.kt
+++ b/packages/SystemUI/tests/src/com/android/systemui/battery/BatteryMeterViewTest.kt
@@ -17,6 +17,7 @@ package com.android.systemui.battery
 
 import android.testing.AndroidTestingRunner
 import android.testing.TestableLooper.RunWithLooper
+import android.widget.ImageView
 import androidx.test.filters.SmallTest
 import com.android.systemui.SysuiTestCase
 import com.android.systemui.battery.BatteryMeterView.BatteryEstimateFetcher
@@ -58,6 +59,45 @@ class BatteryMeterViewTest : SysuiTestCase() {
         // No assert needed
     }
 
+    @Test
+    fun isOverheatedChanged_true_drawableGetsTrue() {
+        mBatteryMeterView.setDisplayShieldEnabled(true)
+        val drawable = getBatteryDrawable()
+
+        mBatteryMeterView.onIsOverheatedChanged(true)
+
+        assertThat(drawable.displayShield).isTrue()
+    }
+
+    @Test
+    fun isOverheatedChanged_false_drawableGetsFalse() {
+        mBatteryMeterView.setDisplayShieldEnabled(true)
+        val drawable = getBatteryDrawable()
+
+        // Start as true
+        mBatteryMeterView.onIsOverheatedChanged(true)
+
+        // Update to false
+        mBatteryMeterView.onIsOverheatedChanged(false)
+
+        assertThat(drawable.displayShield).isFalse()
+    }
+
+    @Test
+    fun isOverheatedChanged_true_featureflagOff_drawableGetsFalse() {
+        mBatteryMeterView.setDisplayShieldEnabled(false)
+        val drawable = getBatteryDrawable()
+
+        mBatteryMeterView.onIsOverheatedChanged(true)
+
+        assertThat(drawable.displayShield).isFalse()
+    }
+
+    private fun getBatteryDrawable(): AccessorizedBatteryDrawable {
+        return (mBatteryMeterView.getChildAt(0) as ImageView)
+                .drawable as AccessorizedBatteryDrawable
+    }
+
     private class Fetcher : BatteryEstimateFetcher {
         override fun fetchBatteryTimeRemainingEstimate(
                 completion: EstimateFetchCompletion) {
@@ -68,4 +108,4 @@ class BatteryMeterViewTest : SysuiTestCase() {
     private companion object {
         const val ESTIMATE = "2 hours 2 minutes"
     }
-}
\ No newline at end of file
+}
diff --git a/packages/SystemUI/tests/src/com/android/systemui/battery/BatterySpecsTest.kt b/packages/SystemUI/tests/src/com/android/systemui/battery/BatterySpecsTest.kt
new file mode 100644
index 0000000000000..39cb0476e429a
--- /dev/null
+++ b/packages/SystemUI/tests/src/com/android/systemui/battery/BatterySpecsTest.kt
@@ -0,0 +1,101 @@
+/*
+ * Copyright (C) 2022 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.android.systemui.battery
+
+import androidx.test.filters.SmallTest
+import com.android.systemui.SysuiTestCase
+import com.android.systemui.battery.BatterySpecs.BATTERY_HEIGHT
+import com.android.systemui.battery.BatterySpecs.BATTERY_HEIGHT_WITH_SHIELD
+import com.android.systemui.battery.BatterySpecs.BATTERY_WIDTH
+import com.android.systemui.battery.BatterySpecs.BATTERY_WIDTH_WITH_SHIELD
+import com.google.common.truth.Truth.assertThat
+import org.junit.Test
+
+@SmallTest
+class BatterySpecsTest : SysuiTestCase() {
+    @Test
+    fun getFullBatteryHeight_shieldFalse_returnsMainHeight() {
+        val fullHeight = BatterySpecs.getFullBatteryHeight(56f, displayShield = false)
+
+        assertThat(fullHeight).isEqualTo(56f)
+    }
+
+    @Test
+    fun getFullBatteryHeight_shieldTrue_returnsMainHeightPlusShield() {
+        val mainHeight = BATTERY_HEIGHT * 5
+        val fullHeight = BatterySpecs.getFullBatteryHeight(mainHeight, displayShield = true)
+
+        // Since the main battery was scaled 5x, the output height should also be scaled 5x
+        val expectedFullHeight = BATTERY_HEIGHT_WITH_SHIELD * 5
+
+        assertThat(fullHeight).isWithin(.0001f).of(expectedFullHeight)
+    }
+
+    @Test
+    fun getFullBatteryWidth_shieldFalse_returnsMainWidth() {
+        val fullWidth = BatterySpecs.getFullBatteryWidth(33f, displayShield = false)
+
+        assertThat(fullWidth).isEqualTo(33f)
+    }
+
+    @Test
+    fun getFullBatteryWidth_shieldTrue_returnsMainWidthPlusShield() {
+        val mainWidth = BATTERY_WIDTH * 3.3f
+
+        val fullWidth = BatterySpecs.getFullBatteryWidth(mainWidth, displayShield = true)
+
+        // Since the main battery was scaled 3.3x, the output width should also be scaled 5x
+        val expectedFullWidth = BATTERY_WIDTH_WITH_SHIELD * 3.3f
+        assertThat(fullWidth).isWithin(.0001f).of(expectedFullWidth)
+    }
+
+    @Test
+    fun getMainBatteryHeight_shieldFalse_returnsFullHeight() {
+        val mainHeight = BatterySpecs.getMainBatteryHeight(89f, displayShield = false)
+
+        assertThat(mainHeight).isEqualTo(89f)
+    }
+
+    @Test
+    fun getMainBatteryHeight_shieldTrue_returnsNotFullHeight() {
+        val fullHeight = BATTERY_HEIGHT_WITH_SHIELD * 7.7f
+
+        val mainHeight = BatterySpecs.getMainBatteryHeight(fullHeight, displayShield = true)
+
+        // Since the full height was scaled 7.7x, the main height should also be scaled 7.7x.
+        val expectedHeight = BATTERY_HEIGHT * 7.7f
+        assertThat(mainHeight).isWithin(.0001f).of(expectedHeight)
+    }
+
+    @Test
+    fun getMainBatteryWidth_shieldFalse_returnsFullWidth() {
+        val mainWidth = BatterySpecs.getMainBatteryWidth(2345f, displayShield = false)
+
+        assertThat(mainWidth).isEqualTo(2345f)
+    }
+
+    @Test
+    fun getMainBatteryWidth_shieldTrue_returnsNotFullWidth() {
+        val fullWidth = BATTERY_WIDTH_WITH_SHIELD * 0.6f
+
+        val mainWidth = BatterySpecs.getMainBatteryWidth(fullWidth, displayShield = true)
+
+        // Since the full width was scaled 0.6x, the main height should also be scaled 0.6x.
+        val expectedWidth = BATTERY_WIDTH * 0.6f
+        assertThat(mainWidth).isWithin(.0001f).of(expectedWidth)
+    }
+}
diff --git a/packages/SystemUI/tests/src/com/android/systemui/statusbar/policy/BatteryControllerTest.java b/packages/SystemUI/tests/src/com/android/systemui/statusbar/policy/BatteryControllerTest.java
index 43d0fe9559b67..1eee08c221877 100644
--- a/packages/SystemUI/tests/src/com/android/systemui/statusbar/policy/BatteryControllerTest.java
+++ b/packages/SystemUI/tests/src/com/android/systemui/statusbar/policy/BatteryControllerTest.java
@@ -221,4 +221,33 @@ public class BatteryControllerTest extends SysuiTestCase {
 
         Assert.assertFalse(mBatteryController.isChargingSourceDock());
     }
+
+    @Test
+    public void batteryStateChanged_healthNotOverheated_outputsFalse() {
+        Intent intent = new Intent(Intent.ACTION_BATTERY_CHANGED);
+        intent.putExtra(BatteryManager.EXTRA_HEALTH, BatteryManager.BATTERY_HEALTH_GOOD);
+
+        mBatteryController.onReceive(getContext(), intent);
+
+        Assert.assertFalse(mBatteryController.isOverheated());
+    }
+
+    @Test
+    public void batteryStateChanged_healthOverheated_outputsTrue() {
+        Intent intent = new Intent(Intent.ACTION_BATTERY_CHANGED);
+        intent.putExtra(BatteryManager.EXTRA_HEALTH, BatteryManager.BATTERY_HEALTH_OVERHEAT);
+
+        mBatteryController.onReceive(getContext(), intent);
+
+        Assert.assertTrue(mBatteryController.isOverheated());
+    }
+
+    @Test
+    public void batteryStateChanged_noHealthGiven_outputsFalse() {
+        Intent intent = new Intent(Intent.ACTION_BATTERY_CHANGED);
+
+        mBatteryController.onReceive(getContext(), intent);
+
+        Assert.assertFalse(mBatteryController.isOverheated());
+    }
 }