Merge "Call preserveSurfaces when detaching children." into rvc-dev

1 files changed, 26 insertions, 16 deletions

diff --git a/services/core/java/com/android/server/wm/WindowStateAnimator.java b/services/core/java/com/android/server/wm/WindowStateAnimator.java
index 42c21930bdf7..c0252363a159 100644
--- a/services/core/java/com/android/server/wm/WindowStateAnimator.java
+++ b/services/core/java/com/android/server/wm/WindowStateAnimator.java
@@ -418,25 +418,25 @@ class WindowStateAnimator {
         if (!mDestroyPreservedSurfaceUponRedraw) {
             return;
         }
-        if (mSurfaceController != null) {
-            if (mPendingDestroySurface != null) {
-                // If we are preserving a surface but we aren't relaunching that means
-                // we are just doing an in-place switch. In that case any SurfaceFlinger side
-                // child layers need to be reparented to the new surface to make this
-                // transparent to the app.
-                if (mWin.mActivityRecord == null || mWin.mActivityRecord.isRelaunching() == false) {
-                    mPostDrawTransaction.reparentChildren(
-                        mPendingDestroySurface.getClientViewRootSurface(),
-                        mSurfaceController.mSurfaceControl).apply();
-                }
-            }
+
+        // If we are preserving a surface but we aren't relaunching that means
+        // we are just doing an in-place switch. In that case any SurfaceFlinger side
+        // child layers need to be reparented to the new surface to make this
+        // transparent to the app.
+        // If the children are detached, we don't want to reparent them to the new surface.
+        // Instead let the children get removed when the old surface is deleted.
+        if (mSurfaceController != null && mPendingDestroySurface != null && !mChildrenDetached
+                && (mWin.mActivityRecord == null || !mWin.mActivityRecord.isRelaunching())) {
+            mPostDrawTransaction.reparentChildren(
+                    mPendingDestroySurface.getClientViewRootSurface(),
+                    mSurfaceController.mSurfaceControl).apply();
         }
 
         destroyDeferredSurfaceLocked();
         mDestroyPreservedSurfaceUponRedraw = false;
     }
 
-    void markPreservedSurfaceForDestroy() {
+    private void markPreservedSurfaceForDestroy() {
         if (mDestroyPreservedSurfaceUponRedraw
                 && !mService.mDestroyPreservedSurface.contains(mWin)) {
             mService.mDestroyPreservedSurface.add(mWin);
@@ -1363,9 +1363,13 @@ class WindowStateAnimator {
         if (mPendingDestroySurface != null && mDestroyPreservedSurfaceUponRedraw) {
             final SurfaceControl pendingSurfaceControl = mPendingDestroySurface.mSurfaceControl;
             mPostDrawTransaction.reparent(pendingSurfaceControl, null);
-            mPostDrawTransaction.reparentChildren(
-                mPendingDestroySurface.getClientViewRootSurface(),
-                mSurfaceController.mSurfaceControl);
+            // If the children are detached, we don't want to reparent them to the new surface.
+            // Instead let the children get removed when the old surface is deleted.
+            if (!mChildrenDetached) {
+                mPostDrawTransaction.reparentChildren(
+                        mPendingDestroySurface.getClientViewRootSurface(),
+                        mSurfaceController.mSurfaceControl);
+            }
         }
 
         SurfaceControl.mergeToGlobalTransaction(mPostDrawTransaction);
@@ -1593,6 +1597,12 @@ class WindowStateAnimator {
             mSurfaceController.detachChildren();
         }
         mChildrenDetached = true;
+        // If the children are detached, it means the app is exiting. We don't want to tear the
+        // content down too early, otherwise we could end up with a flicker. By preserving the
+        // current surface, we ensure the content remains on screen until the window is completely
+        // removed. It also ensures that the old surface is cleaned up when started again since it
+        // forces mSurfaceController to be set to null.
+        preserveSurfaceLocked();
     }
 
     void setOffsetPositionForStackResize(boolean offsetPositionForStackResize) {