Merge "Fix NPE in adding/removing presentation" into main

3 files changed, 32 insertions, 11 deletions

diff --git a/services/core/java/com/android/server/wm/TransitionController.java b/services/core/java/com/android/server/wm/TransitionController.java
index 51c3da098020..02b53b0106b8 100644
--- a/services/core/java/com/android/server/wm/TransitionController.java
+++ b/services/core/java/com/android/server/wm/TransitionController.java
@@ -512,9 +512,14 @@ class TransitionController {
         return false;
     }
 
+    /** Returns {@code true} if the display contains a collecting transition. */
+    boolean isCollectingTransitionOnDisplay(@NonNull DisplayContent dc) {
+        return mCollectingTransition != null && mCollectingTransition.isOnDisplay(dc);
+    }
+
     /** Returns {@code true} if the display contains a running or pending transition. */
     boolean isTransitionOnDisplay(@NonNull DisplayContent dc) {
-        if (mCollectingTransition != null && mCollectingTransition.isOnDisplay(dc)) {
+        if (isCollectingTransitionOnDisplay(dc)) {
             return true;
         }
         for (int i = mWaitingTransitions.size() - 1; i >= 0; --i) {
diff --git a/services/core/java/com/android/server/wm/WindowManagerService.java b/services/core/java/com/android/server/wm/WindowManagerService.java
index a9bb690d4e53..3ccbc868377e 100644
--- a/services/core/java/com/android/server/wm/WindowManagerService.java
+++ b/services/core/java/com/android/server/wm/WindowManagerService.java
@@ -1845,9 +1845,12 @@ public class WindowManagerService extends IWindowManager.Stub
             // Only a presentation window needs a transition because its visibility affets the
             // lifecycle of apps below (b/390481865).
             if (enablePresentationForConnectedDisplays() && win.isPresentation()) {
-                Transition transition = null;
+                final boolean wasTransitionOnDisplay =
+                        win.mTransitionController.isCollectingTransitionOnDisplay(displayContent);
+                Transition newlyCreatedTransition = null;
                 if (!win.mTransitionController.isCollecting()) {
-                    transition = win.mTransitionController.createAndStartCollecting(TRANSIT_OPEN);
+                    newlyCreatedTransition =
+                            win.mTransitionController.createAndStartCollecting(TRANSIT_OPEN);
                 }
                 win.mTransitionController.collect(win.mToken);
                 res |= addWindowInner(win, displayPolicy, activity, displayContent, outInsetsState,
@@ -1856,9 +1859,14 @@ public class WindowManagerService extends IWindowManager.Stub
                 // A presentation hides all activities behind on the same display.
                 win.mDisplayContent.ensureActivitiesVisible(/*starting=*/ null,
                         /*notifyClients=*/ true);
-                win.mTransitionController.getCollectingTransition().setReady(win.mToken, true);
-                if (transition != null) {
-                    win.mTransitionController.requestStartTransition(transition, null,
+                if (!wasTransitionOnDisplay && win.mTransitionController
+                        .isCollectingTransitionOnDisplay(displayContent)) {
+                    // Set the display ready only when the display gets added to the collecting
+                    // transition in this operation.
+                    win.mTransitionController.setReady(win.mToken);
+                }
+                if (newlyCreatedTransition != null) {
+                    win.mTransitionController.requestStartTransition(newlyCreatedTransition, null,
                             null /* remoteTransition */, null /* displayChange */);
                 }
             } else {
diff --git a/services/core/java/com/android/server/wm/WindowState.java b/services/core/java/com/android/server/wm/WindowState.java
index 22ddd5f39b24..d43aba0d218d 100644
--- a/services/core/java/com/android/server/wm/WindowState.java
+++ b/services/core/java/com/android/server/wm/WindowState.java
@@ -2365,9 +2365,12 @@ class WindowState extends WindowContainer<WindowState> implements WindowManagerP
             // Only a presentation window needs a transition because its visibility affets the
             // lifecycle of apps below (b/390481865).
             if (enablePresentationForConnectedDisplays() && isPresentation()) {
-                Transition transition = null;
+                final boolean wasTransitionOnDisplay =
+                        mTransitionController.isCollectingTransitionOnDisplay(displayContent);
+                Transition newlyCreatedTransition = null;
                 if (!mTransitionController.isCollecting()) {
-                    transition = mTransitionController.createAndStartCollecting(TRANSIT_CLOSE);
+                    newlyCreatedTransition =
+                            mTransitionController.createAndStartCollecting(TRANSIT_CLOSE);
                 }
                 mTransitionController.collect(mToken);
                 mAnimatingExit = true;
@@ -2376,9 +2379,14 @@ class WindowState extends WindowContainer<WindowState> implements WindowManagerP
                 // A presentation hides all activities behind on the same display.
                 mDisplayContent.ensureActivitiesVisible(/*starting=*/ null,
                         /*notifyClients=*/ true);
-                mTransitionController.getCollectingTransition().setReady(mToken, true);
-                if (transition != null) {
-                    mTransitionController.requestStartTransition(transition, null,
+                if (!wasTransitionOnDisplay && mTransitionController
+                        .isCollectingTransitionOnDisplay(displayContent)) {
+                    // Set the display ready only when the display gets added to the collecting
+                    // transition in this operation.
+                    mTransitionController.setReady(mToken);
+                }
+                if (newlyCreatedTransition != null) {
+                    mTransitionController.requestStartTransition(newlyCreatedTransition, null,
                             null /* remoteTransition */, null /* displayChange */);
                 }
             } else {