Skip updating system bar attributes while relaunching related apps

The appearance of system bars might change while relaunching apps. We
don't report the intermediate state to system UI. Otherwise, it might
trigger redundant effects.

Fix: 255353969
Test: Rotate an app which will relaunch itself during rotation
      (ex: calculator) and see if onSystemBarAttributesChanged
      is only called once.
Change-Id: Ie7241a9bbba19688755bdbb1ddc2abe5f7cb5eac

3 files changed, 75 insertions, 9 deletions

diff --git a/services/core/java/com/android/server/wm/ActivityRecord.java b/services/core/java/com/android/server/wm/ActivityRecord.java
index ccab96888e8f..27f8c5c2aa11 100644
--- a/services/core/java/com/android/server/wm/ActivityRecord.java
+++ b/services/core/java/com/android/server/wm/ActivityRecord.java
@@ -1750,6 +1750,7 @@ final class ActivityRecord extends WindowToken implements WindowManagerService.A
         }
 
         prevDc.mClosingApps.remove(this);
+        prevDc.getDisplayPolicy().removeRelaunchingApp(this);
 
         if (prevDc.mFocusedApp == this) {
             prevDc.setFocusedApp(null);
@@ -3969,6 +3970,9 @@ final class ActivityRecord extends WindowToken implements WindowManagerService.A
     void startRelaunching() {
         if (mPendingRelaunchCount == 0) {
             mRelaunchStartTime = SystemClock.elapsedRealtime();
+            if (mVisibleRequested) {
+                mDisplayContent.getDisplayPolicy().addRelaunchingApp(this);
+            }
         }
         clearAllDrawn();
 
@@ -3982,7 +3986,7 @@ final class ActivityRecord extends WindowToken implements WindowManagerService.A
             mPendingRelaunchCount--;
             if (mPendingRelaunchCount == 0 && !isClientVisible()) {
                 // Don't count if the client won't report drawn.
-                mRelaunchStartTime = 0;
+                finishOrAbortReplacingWindow();
             }
         } else {
             // Update keyguard flags upon finishing relaunch.
@@ -4003,7 +4007,12 @@ final class ActivityRecord extends WindowToken implements WindowManagerService.A
             return;
         }
         mPendingRelaunchCount = 0;
+        finishOrAbortReplacingWindow();
+    }
+
+    void finishOrAbortReplacingWindow() {
         mRelaunchStartTime = 0;
+        mDisplayContent.getDisplayPolicy().removeRelaunchingApp(this);
     }
 
     /**
@@ -5112,6 +5121,9 @@ final class ActivityRecord extends WindowToken implements WindowManagerService.A
             mTaskSupervisor.onProcessActivityStateChanged(app, false /* forceBatch */);
         }
         logAppCompatState();
+        if (!visible) {
+            finishOrAbortReplacingWindow();
+        }
     }
 
     /**
diff --git a/services/core/java/com/android/server/wm/DisplayPolicy.java b/services/core/java/com/android/server/wm/DisplayPolicy.java
index 2688ff757f64..2c289c99d3da 100644
--- a/services/core/java/com/android/server/wm/DisplayPolicy.java
+++ b/services/core/java/com/android/server/wm/DisplayPolicy.java
@@ -282,6 +282,12 @@ public class DisplayPolicy {
 
     private final ArraySet<WindowState> mInsetsSourceWindowsExceptIme = new ArraySet<>();
 
+    /** Apps which are controlling the appearance of system bars */
+    private final ArraySet<ActivityRecord> mSystemBarColorApps = new ArraySet<>();
+
+    /** Apps which are relaunching and were controlling the appearance of system bars */
+    private final ArraySet<ActivityRecord> mRelaunchingSystemBarColorApps = new ArraySet<>();
+
     private boolean mIsFreeformWindowOverlappingWithNavBar;
 
     private boolean mLastImmersiveMode;
@@ -1550,6 +1556,7 @@ public class DisplayPolicy {
         mStatusBarBackgroundWindows.clear();
         mStatusBarColorCheckedBounds.setEmpty();
         mStatusBarBackgroundCheckedBounds.setEmpty();
+        mSystemBarColorApps.clear();
 
         mAllowLockscreenWhenOn = false;
         mShowingDream = false;
@@ -1626,6 +1633,7 @@ public class DisplayPolicy {
                             win.mAttrs.insetsFlags.appearance & APPEARANCE_LIGHT_STATUS_BARS,
                             new Rect(win.getFrame())));
                     mStatusBarColorCheckedBounds.union(sTmpRect);
+                    addSystemBarColorApp(win);
                 }
             }
 
@@ -1638,6 +1646,7 @@ public class DisplayPolicy {
             if (isOverlappingWithNavBar) {
                 if (mNavBarColorWindowCandidate == null) {
                     mNavBarColorWindowCandidate = win;
+                    addSystemBarColorApp(win);
                 }
                 if (mNavBarBackgroundWindow == null) {
                     mNavBarBackgroundWindow = win;
@@ -1656,9 +1665,11 @@ public class DisplayPolicy {
             }
         } else if (win.isDimming()) {
             if (mStatusBar != null) {
-                addStatusBarAppearanceRegionsForDimmingWindow(
+                if (addStatusBarAppearanceRegionsForDimmingWindow(
                         win.mAttrs.insetsFlags.appearance & APPEARANCE_LIGHT_STATUS_BARS,
-                        mStatusBar.getFrame(), win.getBounds(), win.getFrame());
+                        mStatusBar.getFrame(), win.getBounds(), win.getFrame())) {
+                    addSystemBarColorApp(win);
+                }
             }
             if (isOverlappingWithNavBar && mNavBarColorWindowCandidate == null) {
                 mNavBarColorWindowCandidate = win;
@@ -1666,18 +1677,21 @@ public class DisplayPolicy {
         }
     }
 
-    private void addStatusBarAppearanceRegionsForDimmingWindow(int appearance, Rect statusBarFrame,
-            Rect winBounds, Rect winFrame) {
+    /**
+     * Returns true if mStatusBarAppearanceRegionList is changed.
+     */
+    private boolean addStatusBarAppearanceRegionsForDimmingWindow(
+            int appearance, Rect statusBarFrame, Rect winBounds, Rect winFrame) {
         if (!sTmpRect.setIntersect(winBounds, statusBarFrame)) {
-            return;
+            return false;
         }
         if (mStatusBarColorCheckedBounds.contains(sTmpRect)) {
-            return;
+            return false;
         }
         if (appearance == 0 || !sTmpRect2.setIntersect(winFrame, statusBarFrame)) {
             mStatusBarAppearanceRegionList.add(new AppearanceRegion(0, new Rect(winBounds)));
             mStatusBarColorCheckedBounds.union(sTmpRect);
-            return;
+            return true;
         }
         // A dimming window can divide status bar into different appearance regions (up to 3).
         // +---------+-------------+---------+
@@ -1706,6 +1720,14 @@ public class DisplayPolicy {
             // We don't have vertical status bar yet, so we don't handle the other orientation.
         }
         mStatusBarColorCheckedBounds.union(sTmpRect);
+        return true;
+    }
+
+    private void addSystemBarColorApp(WindowState win) {
+        final ActivityRecord app = win.mActivityRecord;
+        if (app != null) {
+            mSystemBarColorApps.add(app);
+        }
     }
 
     /**
@@ -2202,6 +2224,25 @@ public class DisplayPolicy {
         return mDisplayContent.getInsetsPolicy();
     }
 
+    /**
+     * Called when an app has started replacing its main window.
+     */
+    void addRelaunchingApp(ActivityRecord app) {
+        if (mSystemBarColorApps.contains(app)) {
+            mRelaunchingSystemBarColorApps.add(app);
+        }
+    }
+
+    /**
+     * Called when an app has finished replacing its main window or aborted.
+     */
+    void removeRelaunchingApp(ActivityRecord app) {
+        final boolean removed = mRelaunchingSystemBarColorApps.remove(app);
+        if (removed & mRelaunchingSystemBarColorApps.isEmpty()) {
+            updateSystemBarAttributes();
+        }
+    }
+
     void resetSystemBarAttributes() {
         mLastDisableFlags = 0;
         updateSystemBarAttributes();
@@ -2244,6 +2285,11 @@ public class DisplayPolicy {
         final int displayId = getDisplayId();
         final int disableFlags = win.getDisableFlags();
         final int opaqueAppearance = updateSystemBarsLw(win, disableFlags);
+        if (!mRelaunchingSystemBarColorApps.isEmpty()) {
+            // The appearance of system bars might change while relaunching apps. We don't report
+            // the intermediate state to system UI. Otherwise, it might trigger redundant effects.
+            return;
+        }
         final WindowState navColorWin = chooseNavigationColorWindowLw(mNavBarColorWindowCandidate,
                 mDisplayContent.mInputMethodWindow, mNavigationBarPosition);
         final boolean isNavbarColorManagedByIme =
@@ -2707,6 +2753,14 @@ public class DisplayPolicy {
             pw.print(prefix); pw.print("mTopFullscreenOpaqueWindowState=");
             pw.println(mTopFullscreenOpaqueWindowState);
         }
+        if (!mSystemBarColorApps.isEmpty()) {
+            pw.print(prefix); pw.print("mSystemBarColorApps=");
+            pw.println(mSystemBarColorApps);
+        }
+        if (!mRelaunchingSystemBarColorApps.isEmpty()) {
+            pw.print(prefix); pw.print("mRelaunchingSystemBarColorApps=");
+            pw.println(mRelaunchingSystemBarColorApps);
+        }
         if (mNavBarColorWindowCandidate != null) {
             pw.print(prefix); pw.print("mNavBarColorWindowCandidate=");
             pw.println(mNavBarColorWindowCandidate);
diff --git a/services/core/java/com/android/server/wm/WindowState.java b/services/core/java/com/android/server/wm/WindowState.java
index a42cec9c06fb..337f6672cd5a 100644
--- a/services/core/java/com/android/server/wm/WindowState.java
+++ b/services/core/java/com/android/server/wm/WindowState.java
@@ -6021,7 +6021,7 @@ class WindowState extends WindowContainer<WindowState> implements WindowManagerP
             final long duration =
                     SystemClock.elapsedRealtime() - mActivityRecord.mRelaunchStartTime;
             Slog.i(TAG, "finishDrawing of relaunch: " + this + " " + duration + "ms");
-            mActivityRecord.mRelaunchStartTime = 0;
+            mActivityRecord.finishOrAbortReplacingWindow();
         }
         if (mActivityRecord != null && mAttrs.type == TYPE_APPLICATION_STARTING) {
             mWmService.mAtmService.mTaskSupervisor.getActivityMetricsLogger()