Merge "Put window decors at one place" into tm-qpr-dev

libs/WindowManager/Shell/src/com/android/wm/shell/dagger/WMShellBaseModule.java

@@ -292,17 +292,17 @@ public abstract class WMShellBaseModule {
     // Workaround for dynamic overriding with a default implementation, see {@link DynamicOverride}
     @BindsOptionalOf
     @DynamicOverride
-    abstract FullscreenTaskListener<?> optionalFullscreenTaskListener();
+    abstract FullscreenTaskListener optionalFullscreenTaskListener();
 
     @WMSingleton
     @Provides
-    static FullscreenTaskListener<?> provideFullscreenTaskListener(
+    static FullscreenTaskListener provideFullscreenTaskListener(
-            @DynamicOverride Optional<FullscreenTaskListener<?>> fullscreenTaskListener,
+            @DynamicOverride Optional<FullscreenTaskListener> fullscreenTaskListener,
             ShellInit shellInit,
             ShellTaskOrganizer shellTaskOrganizer,
             SyncTransactionQueue syncQueue,
             Optional<RecentTasksController> recentTasksOptional,
-            Optional<WindowDecorViewModel<?>> windowDecorViewModelOptional) {
+            Optional<WindowDecorViewModel> windowDecorViewModelOptional) {
         if (fullscreenTaskListener.isPresent()) {
             return fullscreenTaskListener.get();
         } else {
@@ -316,7 +316,7 @@ public abstract class WMShellBaseModule {
     //
 
     @BindsOptionalOf
-    abstract WindowDecorViewModel<?> optionalWindowDecorViewModel();
+    abstract WindowDecorViewModel optionalWindowDecorViewModel();
 
     //
     // Unfold transition
@@ -768,7 +768,7 @@ public abstract class WMShellBaseModule {
             Optional<SplitScreenController> splitScreenOptional,
             Optional<Pip> pipOptional,
             Optional<PipTouchHandler> pipTouchHandlerOptional,
-            FullscreenTaskListener<?> fullscreenTaskListener,
+            FullscreenTaskListener fullscreenTaskListener,
             Optional<UnfoldAnimationController> unfoldAnimationController,
             Optional<UnfoldTransitionHandler> unfoldTransitionHandler,
             Optional<FreeformComponents> freeformComponents,

libs/WindowManager/Shell/src/com/android/wm/shell/dagger/WMShellModule.java

@@ -55,7 +55,6 @@ import com.android.wm.shell.freeform.FreeformComponents;
 import com.android.wm.shell.freeform.FreeformTaskListener;
 import com.android.wm.shell.freeform.FreeformTaskTransitionHandler;
 import com.android.wm.shell.freeform.FreeformTaskTransitionObserver;
-import com.android.wm.shell.fullscreen.FullscreenTaskListener;
 import com.android.wm.shell.kidsmode.KidsModeTaskOrganizer;
 import com.android.wm.shell.onehanded.OneHandedController;
 import com.android.wm.shell.pip.Pip;
@@ -183,7 +182,7 @@ public abstract class WMShellModule {
 
     @WMSingleton
     @Provides
-    static WindowDecorViewModel<?> provideWindowDecorViewModel(
+    static WindowDecorViewModel provideWindowDecorViewModel(
             Context context,
             @ShellMainThread Handler mainHandler,
             @ShellMainThread Choreographer mainChoreographer,
@@ -209,7 +208,7 @@ public abstract class WMShellModule {
     @Provides
     @DynamicOverride
     static FreeformComponents provideFreeformComponents(
-            FreeformTaskListener<?> taskListener,
+            FreeformTaskListener taskListener,
             FreeformTaskTransitionHandler transitionHandler,
             FreeformTaskTransitionObserver transitionObserver) {
         return new FreeformComponents(
@@ -218,18 +217,18 @@ public abstract class WMShellModule {
 
     @WMSingleton
     @Provides
-    static FreeformTaskListener<?> provideFreeformTaskListener(
+    static FreeformTaskListener provideFreeformTaskListener(
             Context context,
             ShellInit shellInit,
             ShellTaskOrganizer shellTaskOrganizer,
             Optional<DesktopModeTaskRepository> desktopModeTaskRepository,
-            WindowDecorViewModel<?> windowDecorViewModel) {
+            WindowDecorViewModel windowDecorViewModel) {
         // TODO(b/238217847): Temporarily add this check here until we can remove the dynamic
         //                    override for this controller from the base module
         ShellInit init = FreeformComponents.isFreeformEnabled(context)
                 ? shellInit
                 : null;
-        return new FreeformTaskListener<>(init, shellTaskOrganizer, desktopModeTaskRepository,
+        return new FreeformTaskListener(init, shellTaskOrganizer, desktopModeTaskRepository,
                 windowDecorViewModel);
     }
 
@@ -238,7 +237,7 @@ public abstract class WMShellModule {
     static FreeformTaskTransitionHandler provideFreeformTaskTransitionHandler(
             ShellInit shellInit,
             Transitions transitions,
-            WindowDecorViewModel<?> windowDecorViewModel) {
+            WindowDecorViewModel windowDecorViewModel) {
         return new FreeformTaskTransitionHandler(shellInit, transitions, windowDecorViewModel);
     }
 
@@ -248,10 +247,9 @@ public abstract class WMShellModule {
             Context context,
             ShellInit shellInit,
             Transitions transitions,
-            FullscreenTaskListener<?> fullscreenTaskListener,
+            WindowDecorViewModel windowDecorViewModel) {
-            FreeformTaskListener<?> freeformTaskListener) {
         return new FreeformTaskTransitionObserver(
-                context, shellInit, transitions, fullscreenTaskListener, freeformTaskListener);
+                context, shellInit, transitions, windowDecorViewModel);
     }
 
     //

libs/WindowManager/Shell/src/com/android/wm/shell/freeform/FreeformTaskListener.java

@@ -19,12 +19,8 @@ package com.android.wm.shell.freeform;
 import static com.android.wm.shell.ShellTaskOrganizer.TASK_LISTENER_TYPE_FREEFORM;
 
 import android.app.ActivityManager.RunningTaskInfo;
-import android.util.Log;
 import android.util.SparseArray;
 import android.view.SurfaceControl;
-import android.window.TransitionInfo;
-
-import androidx.annotation.Nullable;
 
 import com.android.internal.protolog.common.ProtoLog;
 import com.android.wm.shell.ShellTaskOrganizer;
@@ -41,31 +37,26 @@ import java.util.Optional;
 /**
  * {@link ShellTaskOrganizer.TaskListener} for {@link
  * ShellTaskOrganizer#TASK_LISTENER_TYPE_FREEFORM}.
- *
- * @param <T> the type of window decoration instance
  */
-public class FreeformTaskListener<T extends AutoCloseable>
+public class FreeformTaskListener implements ShellTaskOrganizer.TaskListener {
-        implements ShellTaskOrganizer.TaskListener {
     private static final String TAG = "FreeformTaskListener";
 
     private final ShellTaskOrganizer mShellTaskOrganizer;
     private final Optional<DesktopModeTaskRepository> mDesktopModeTaskRepository;
-    private final WindowDecorViewModel<T> mWindowDecorationViewModel;
+    private final WindowDecorViewModel mWindowDecorationViewModel;
 
-    private final SparseArray<State<T>> mTasks = new SparseArray<>();
+    private final SparseArray<State> mTasks = new SparseArray<>();
-    private final SparseArray<T> mWindowDecorOfVanishedTasks = new SparseArray<>();
 
-    private static class State<T extends AutoCloseable> {
+    private static class State {
         RunningTaskInfo mTaskInfo;
         SurfaceControl mLeash;
-        T mWindowDecoration;
     }
 
     public FreeformTaskListener(
             ShellInit shellInit,
             ShellTaskOrganizer shellTaskOrganizer,
             Optional<DesktopModeTaskRepository> desktopModeTaskRepository,
-            WindowDecorViewModel<T> windowDecorationViewModel) {
+            WindowDecorViewModel windowDecorationViewModel) {
         mShellTaskOrganizer = shellTaskOrganizer;
         mWindowDecorationViewModel = windowDecorationViewModel;
         mDesktopModeTaskRepository = desktopModeTaskRepository;
@@ -80,12 +71,17 @@ public class FreeformTaskListener<T extends AutoCloseable>
 
     @Override
     public void onTaskAppeared(RunningTaskInfo taskInfo, SurfaceControl leash) {
+        if (mTasks.get(taskInfo.taskId) != null) {
+            throw new IllegalStateException("Task appeared more than once: #" + taskInfo.taskId);
+        }
         ProtoLog.v(ShellProtoLogGroup.WM_SHELL_TASK_ORG, "Freeform Task Appeared: #%d",
                 taskInfo.taskId);
-        final State<T> state = createOrUpdateTaskState(taskInfo, leash);
+        final State state = new State();
+        state.mTaskInfo = taskInfo;
+        state.mLeash = leash;
+        mTasks.put(taskInfo.taskId, state);
         if (!Transitions.ENABLE_SHELL_TRANSITIONS) {
             SurfaceControl.Transaction t = new SurfaceControl.Transaction();
-            state.mWindowDecoration =
             mWindowDecorationViewModel.createWindowDecoration(taskInfo, leash, t, t);
             t.apply();
         }
@@ -97,28 +93,8 @@ public class FreeformTaskListener<T extends AutoCloseable>
         }
     }
 
-    private State<T> createOrUpdateTaskState(RunningTaskInfo taskInfo, SurfaceControl leash) {
-        State<T> state = mTasks.get(taskInfo.taskId);
-        if (state != null) {
-            updateTaskInfo(taskInfo);
-            return state;
-        }
-
-        state = new State<>();
-        state.mTaskInfo = taskInfo;
-        state.mLeash = leash;
-        mTasks.put(taskInfo.taskId, state);
-
-        return state;
-    }
-
     @Override
     public void onTaskVanished(RunningTaskInfo taskInfo) {
-        final State<T> state = mTasks.get(taskInfo.taskId);
-        if (state == null) {
-            // This is possible if the transition happens before this method.
-            return;
-        }
         ProtoLog.v(ShellProtoLogGroup.WM_SHELL_TASK_ORG, "Freeform Task Vanished: #%d",
                 taskInfo.taskId);
         mTasks.remove(taskInfo.taskId);
@@ -129,26 +105,18 @@ public class FreeformTaskListener<T extends AutoCloseable>
             mDesktopModeTaskRepository.ifPresent(it -> it.removeActiveTask(taskInfo.taskId));
         }
 
-        if (Transitions.ENABLE_SHELL_TRANSITIONS) {
+        if (!Transitions.ENABLE_SHELL_TRANSITIONS) {
-            // Save window decorations of closing tasks so that we can hand them over to the
+            mWindowDecorationViewModel.destroyWindowDecoration(taskInfo);
-            // transition system if this method happens before the transition. In case where the
-            // transition didn't happen, it'd be cleared when the next transition finished.
-            if (state.mWindowDecoration != null) {
-                mWindowDecorOfVanishedTasks.put(taskInfo.taskId, state.mWindowDecoration);
         }
-            return;
-        }
-        releaseWindowDecor(state.mWindowDecoration);
     }
 
     @Override
     public void onTaskInfoChanged(RunningTaskInfo taskInfo) {
-        final State<T> state = updateTaskInfo(taskInfo);
+        final State state = mTasks.get(taskInfo.taskId);
+        state.mTaskInfo = taskInfo;
         ProtoLog.v(ShellProtoLogGroup.WM_SHELL_TASK_ORG, "Freeform Task Info Changed: #%d",
                 taskInfo.taskId);
-        if (state.mWindowDecoration != null) {
+        mWindowDecorationViewModel.onTaskInfoChanged(state.mTaskInfo);
-            mWindowDecorationViewModel.onTaskInfoChanged(state.mTaskInfo, state.mWindowDecoration);
-        }
 
         if (DesktopModeStatus.IS_SUPPORTED) {
             if (taskInfo.isVisible) {
@@ -159,15 +127,6 @@ public class FreeformTaskListener<T extends AutoCloseable>
         }
     }
 
-    private State<T> updateTaskInfo(RunningTaskInfo taskInfo) {
-        final State<T> state = mTasks.get(taskInfo.taskId);
-        if (state == null) {
-            throw new RuntimeException("Task info changed before appearing: #" + taskInfo.taskId);
-        }
-        state.mTaskInfo = taskInfo;
-        return state;
-    }
-
     @Override
     public void attachChildSurfaceToTask(int taskId, SurfaceControl.Builder b) {
         b.setParent(findTaskSurface(taskId));
@@ -186,103 +145,6 @@ public class FreeformTaskListener<T extends AutoCloseable>
         return mTasks.get(taskId).mLeash;
     }
 
-    /**
-     * Creates a window decoration for a transition.
-     *
-     * @param change the change of this task transition that needs to have the task layer as the
-     *               leash
-     * @return {@code true} if it creates the window decoration; {@code false} otherwise
-     */
-    boolean createWindowDecoration(
-            TransitionInfo.Change change,
-            SurfaceControl.Transaction startT,
-            SurfaceControl.Transaction finishT) {
-        final State<T> state = createOrUpdateTaskState(change.getTaskInfo(), change.getLeash());
-        if (state.mWindowDecoration != null) {
-            return false;
-        }
-        state.mWindowDecoration = mWindowDecorationViewModel.createWindowDecoration(
-                state.mTaskInfo, state.mLeash, startT, finishT);
-        return true;
-    }
-
-    /**
-     * Gives out the ownership of the task's window decoration. The given task is leaving (of has
-     * left) this task listener. This is the transition system asking for the ownership.
-     *
-     * @param taskInfo the maximizing task
-     * @return the window decor of the maximizing task if any
-     */
-    T giveWindowDecoration(
-            RunningTaskInfo taskInfo,
-            SurfaceControl.Transaction startT,
-            SurfaceControl.Transaction finishT) {
-        T windowDecor;
-        final State<T> state = mTasks.get(taskInfo.taskId);
-        if (state != null) {
-            windowDecor = state.mWindowDecoration;
-            state.mWindowDecoration = null;
-        } else {
-            windowDecor =
-                    mWindowDecorOfVanishedTasks.removeReturnOld(taskInfo.taskId);
-        }
-        if (windowDecor == null) {
-            return null;
-        }
-        mWindowDecorationViewModel.setupWindowDecorationForTransition(
-                taskInfo, startT, finishT, windowDecor);
-        return windowDecor;
-    }
-
-    /**
-     * Adopt the incoming window decoration and lets the window decoration prepare for a transition.
-     *
-     * @param change the change of this task transition that needs to have the task layer as the
-     *               leash
-     * @param startT the start transaction of this transition
-     * @param finishT the finish transaction of this transition
-     * @param windowDecor the window decoration to adopt
-     * @return {@code true} if it adopts the window decoration; {@code false} otherwise
-     */
-    boolean adoptWindowDecoration(
-            TransitionInfo.Change change,
-            SurfaceControl.Transaction startT,
-            SurfaceControl.Transaction finishT,
-            @Nullable AutoCloseable windowDecor) {
-        final State<T> state = createOrUpdateTaskState(change.getTaskInfo(), change.getLeash());
-        state.mWindowDecoration = mWindowDecorationViewModel.adoptWindowDecoration(windowDecor);
-        if (state.mWindowDecoration != null) {
-            mWindowDecorationViewModel.setupWindowDecorationForTransition(
-                    state.mTaskInfo, startT, finishT, state.mWindowDecoration);
-            return true;
-        } else {
-            state.mWindowDecoration = mWindowDecorationViewModel.createWindowDecoration(
-                    state.mTaskInfo, state.mLeash, startT, finishT);
-            return false;
-        }
-    }
-
-    void onTaskTransitionFinished() {
-        if (mWindowDecorOfVanishedTasks.size() == 0) {
-            return;
-        }
-        ProtoLog.v(ShellProtoLogGroup.WM_SHELL_TRANSITIONS,
-                "Clearing window decors of vanished tasks. There could be visual defects "
-                + "if any of them is used later in transitions.");
-        for (int i = 0; i < mWindowDecorOfVanishedTasks.size(); ++i) {
-            releaseWindowDecor(mWindowDecorOfVanishedTasks.valueAt(i));
-        }
-        mWindowDecorOfVanishedTasks.clear();
-    }
-
-    private void releaseWindowDecor(T windowDecor) {
-        try {
-            windowDecor.close();
-        } catch (Exception e) {
-            Log.e(TAG, "Failed to release window decoration.", e);
-        }
-    }
-
     @Override
     public void dump(PrintWriter pw, String prefix) {
         final String innerPrefix = prefix + "  ";

libs/WindowManager/Shell/src/com/android/wm/shell/freeform/FreeformTaskTransitionHandler.java

@@ -46,14 +46,14 @@ public class FreeformTaskTransitionHandler
         implements Transitions.TransitionHandler, FreeformTaskTransitionStarter {
 
     private final Transitions mTransitions;
-    private final WindowDecorViewModel<?> mWindowDecorViewModel;
+    private final WindowDecorViewModel mWindowDecorViewModel;
 
     private final List<IBinder> mPendingTransitionTokens = new ArrayList<>();
 
     public FreeformTaskTransitionHandler(
             ShellInit shellInit,
             Transitions transitions,
-            WindowDecorViewModel<?> windowDecorViewModel) {
+            WindowDecorViewModel windowDecorViewModel) {
         mTransitions = transitions;
         mWindowDecorViewModel = windowDecorViewModel;
         if (Transitions.ENABLE_SHELL_TRANSITIONS) {

libs/WindowManager/Shell/src/com/android/wm/shell/freeform/FreeformTaskTransitionObserver.java

@@ -16,13 +16,9 @@
 
 package com.android.wm.shell.freeform;
 
-import static android.app.WindowConfiguration.WINDOWING_MODE_FREEFORM;
-import static android.app.WindowConfiguration.WINDOWING_MODE_FULLSCREEN;
-
 import android.app.ActivityManager;
 import android.content.Context;
 import android.os.IBinder;
-import android.util.Log;
 import android.view.SurfaceControl;
 import android.view.WindowManager;
 import android.window.TransitionInfo;
@@ -31,9 +27,9 @@ import android.window.WindowContainerToken;
 import androidx.annotation.NonNull;
 import androidx.annotation.VisibleForTesting;
 
-import com.android.wm.shell.fullscreen.FullscreenTaskListener;
 import com.android.wm.shell.sysui.ShellInit;
 import com.android.wm.shell.transition.Transitions;
+import com.android.wm.shell.windowdecor.WindowDecorViewModel;
 
 import java.util.ArrayList;
 import java.util.Collections;
@@ -47,23 +43,19 @@ import java.util.Map;
  * be a part of transitions.
  */
 public class FreeformTaskTransitionObserver implements Transitions.TransitionObserver {
-    private static final String TAG = "FreeformTO";
-
     private final Transitions mTransitions;
-    private final FreeformTaskListener<?> mFreeformTaskListener;
+    private final WindowDecorViewModel mWindowDecorViewModel;
-    private final FullscreenTaskListener<?> mFullscreenTaskListener;
 
-    private final Map<IBinder, List<AutoCloseable>> mTransitionToWindowDecors = new HashMap<>();
+    private final Map<IBinder, List<ActivityManager.RunningTaskInfo>> mTransitionToTaskInfo =
+            new HashMap<>();
 
     public FreeformTaskTransitionObserver(
             Context context,
             ShellInit shellInit,
             Transitions transitions,
-            FullscreenTaskListener<?> fullscreenTaskListener,
+            WindowDecorViewModel windowDecorViewModel) {
-            FreeformTaskListener<?> freeformTaskListener) {
         mTransitions = transitions;
-        mFreeformTaskListener = freeformTaskListener;
+        mWindowDecorViewModel = windowDecorViewModel;
-        mFullscreenTaskListener = fullscreenTaskListener;
         if (Transitions.ENABLE_SHELL_TRANSITIONS && FreeformComponents.isFreeformEnabled(context)) {
             shellInit.addInitCallback(this::onInit, this);
         }
@@ -80,7 +72,7 @@ public class FreeformTaskTransitionObserver implements Transitions.TransitionObs
             @NonNull TransitionInfo info,
             @NonNull SurfaceControl.Transaction startT,
             @NonNull SurfaceControl.Transaction finishT) {
-        final ArrayList<AutoCloseable> windowDecors = new ArrayList<>();
+        final ArrayList<ActivityManager.RunningTaskInfo> taskInfoList = new ArrayList<>();
         final ArrayList<WindowContainerToken> taskParents = new ArrayList<>();
         for (TransitionInfo.Change change : info.getChanges()) {
             if ((change.getFlags() & TransitionInfo.FLAG_IS_WALLPAPER) != 0) {
@@ -110,92 +102,40 @@ public class FreeformTaskTransitionObserver implements Transitions.TransitionObs
                     onOpenTransitionReady(change, startT, finishT);
                     break;
                 case WindowManager.TRANSIT_CLOSE: {
-                    onCloseTransitionReady(change, windowDecors, startT, finishT);
+                    taskInfoList.add(change.getTaskInfo());
+                    onCloseTransitionReady(change, startT, finishT);
                     break;
                 }
                 case WindowManager.TRANSIT_CHANGE:
-                    onChangeTransitionReady(info.getType(), change, startT, finishT);
+                    onChangeTransitionReady(change, startT, finishT);
                     break;
             }
         }
-        if (!windowDecors.isEmpty()) {
+        mTransitionToTaskInfo.put(transition, taskInfoList);
-            mTransitionToWindowDecors.put(transition, windowDecors);
-        }
     }
 
     private void onOpenTransitionReady(
             TransitionInfo.Change change,
             SurfaceControl.Transaction startT,
             SurfaceControl.Transaction finishT) {
-        switch (change.getTaskInfo().getWindowingMode()){
+        mWindowDecorViewModel.createWindowDecoration(
-            case WINDOWING_MODE_FREEFORM:
+                change.getTaskInfo(), change.getLeash(), startT, finishT);
-                mFreeformTaskListener.createWindowDecoration(change, startT, finishT);
-                break;
-            case WINDOWING_MODE_FULLSCREEN:
-                mFullscreenTaskListener.createWindowDecoration(change, startT, finishT);
-                break;
-        }
     }
 
     private void onCloseTransitionReady(
             TransitionInfo.Change change,
-            ArrayList<AutoCloseable> windowDecors,
             SurfaceControl.Transaction startT,
             SurfaceControl.Transaction finishT) {
-        final AutoCloseable windowDecor;
+        mWindowDecorViewModel.setupWindowDecorationForTransition(
-        switch (change.getTaskInfo().getWindowingMode()) {
+                change.getTaskInfo(), startT, finishT);
-            case WINDOWING_MODE_FREEFORM:
-                windowDecor = mFreeformTaskListener.giveWindowDecoration(change.getTaskInfo(),
-                        startT, finishT);
-                break;
-            case WINDOWING_MODE_FULLSCREEN:
-                windowDecor = mFullscreenTaskListener.giveWindowDecoration(change.getTaskInfo(),
-                        startT, finishT);
-                break;
-            default:
-                windowDecor = null;
-        }
-        if (windowDecor != null) {
-            windowDecors.add(windowDecor);
-        }
     }
 
     private void onChangeTransitionReady(
-            int type,
             TransitionInfo.Change change,
             SurfaceControl.Transaction startT,
             SurfaceControl.Transaction finishT) {
-        AutoCloseable windowDecor = null;
+        mWindowDecorViewModel.setupWindowDecorationForTransition(
-
-        boolean adopted = false;
-        final ActivityManager.RunningTaskInfo taskInfo = change.getTaskInfo();
-        if (taskInfo.getWindowingMode() == WINDOWING_MODE_FULLSCREEN) {
-            windowDecor = mFreeformTaskListener.giveWindowDecoration(
                 change.getTaskInfo(), startT, finishT);
-            if (windowDecor != null) {
-                adopted = mFullscreenTaskListener.adoptWindowDecoration(
-                        change, startT, finishT, windowDecor);
-            } else {
-                // will return false if it already has the window decor.
-                adopted = mFullscreenTaskListener.createWindowDecoration(change, startT, finishT);
-            }
-        }
-
-        if (taskInfo.getWindowingMode() == WINDOWING_MODE_FREEFORM) {
-            windowDecor = mFullscreenTaskListener.giveWindowDecoration(
-                    change.getTaskInfo(), startT, finishT);
-            if (windowDecor != null) {
-                adopted = mFreeformTaskListener.adoptWindowDecoration(
-                        change, startT, finishT, windowDecor);
-            } else {
-                // will return false if it already has the window decor.
-                adopted = mFreeformTaskListener.createWindowDecoration(change, startT, finishT);
-            }
-        }
-
-        if (!adopted) {
-            releaseWindowDecor(windowDecor);
-        }
     }
 
     @Override
@@ -203,43 +143,32 @@ public class FreeformTaskTransitionObserver implements Transitions.TransitionObs
 
     @Override
     public void onTransitionMerged(@NonNull IBinder merged, @NonNull IBinder playing) {
-        final List<AutoCloseable> windowDecorsOfMerged = mTransitionToWindowDecors.get(merged);
+        final List<ActivityManager.RunningTaskInfo> infoOfMerged =
-        if (windowDecorsOfMerged == null) {
+                mTransitionToTaskInfo.get(merged);
+        if (infoOfMerged == null) {
             // We are adding window decorations of the merged transition to them of the playing
             // transition so if there is none of them there is nothing to do.
             return;
         }
-        mTransitionToWindowDecors.remove(merged);
+        mTransitionToTaskInfo.remove(merged);
 
-        final List<AutoCloseable> windowDecorsOfPlaying = mTransitionToWindowDecors.get(playing);
+        final List<ActivityManager.RunningTaskInfo> infoOfPlaying =
-        if (windowDecorsOfPlaying != null) {
+                mTransitionToTaskInfo.get(playing);
-            windowDecorsOfPlaying.addAll(windowDecorsOfMerged);
+        if (infoOfPlaying != null) {
+            infoOfPlaying.addAll(infoOfMerged);
         } else {
-            mTransitionToWindowDecors.put(playing, windowDecorsOfMerged);
+            mTransitionToTaskInfo.put(playing, infoOfMerged);
         }
     }
 
     @Override
     public void onTransitionFinished(@NonNull IBinder transition, boolean aborted) {
-        final List<AutoCloseable> windowDecors = mTransitionToWindowDecors.getOrDefault(
+        final List<ActivityManager.RunningTaskInfo> taskInfo =
-                transition, Collections.emptyList());
+                mTransitionToTaskInfo.getOrDefault(transition, Collections.emptyList());
-        mTransitionToWindowDecors.remove(transition);
+        mTransitionToTaskInfo.remove(transition);
 
-        for (AutoCloseable windowDecor : windowDecors) {
+        for (int i = 0; i < taskInfo.size(); ++i) {
-            releaseWindowDecor(windowDecor);
+            mWindowDecorViewModel.destroyWindowDecoration(taskInfo.get(i));
-        }
-        mFullscreenTaskListener.onTaskTransitionFinished();
-        mFreeformTaskListener.onTaskTransitionFinished();
-    }
-
-    private static void releaseWindowDecor(AutoCloseable windowDecor) {
-        if (windowDecor == null) {
-            return;
-        }
-        try {
-            windowDecor.close();
-        } catch (Exception e) {
-            Log.e(TAG, "Failed to release window decoration.", e);
         }
     }
 }

libs/WindowManager/Shell/src/com/android/wm/shell/fullscreen/FullscreenTaskListener.java

@@ -22,13 +22,10 @@ import static com.android.wm.shell.ShellTaskOrganizer.taskListenerTypeToString;
 import android.app.ActivityManager;
 import android.app.ActivityManager.RunningTaskInfo;
 import android.graphics.Point;
-import android.util.Log;
 import android.util.SparseArray;
 import android.view.SurfaceControl;
-import android.window.TransitionInfo;
 
 import androidx.annotation.NonNull;
-import androidx.annotation.Nullable;
 
 import com.android.internal.protolog.common.ProtoLog;
 import com.android.wm.shell.ShellTaskOrganizer;
@@ -46,23 +43,20 @@ import java.util.Optional;
   * Organizes tasks presented in {@link android.app.WindowConfiguration.WINDOWING_MODE_FULLSCREEN}.
  * @param <T> the type of window decoration instance
   */
-public class FullscreenTaskListener<T extends AutoCloseable>
+public class FullscreenTaskListener implements ShellTaskOrganizer.TaskListener {
-        implements ShellTaskOrganizer.TaskListener {
     private static final String TAG = "FullscreenTaskListener";
 
     private final ShellTaskOrganizer mShellTaskOrganizer;
 
-    private final SparseArray<State<T>> mTasks = new SparseArray<>();
+    private final SparseArray<State> mTasks = new SparseArray<>();
-    private final SparseArray<T> mWindowDecorOfVanishedTasks = new SparseArray<>();
 
-    private static class State<T extends AutoCloseable> {
+    private static class State {
         RunningTaskInfo mTaskInfo;
         SurfaceControl mLeash;
-        T mWindowDecoration;
     }
     private final SyncTransactionQueue mSyncQueue;
     private final Optional<RecentTasksController> mRecentTasksOptional;
-    private final Optional<WindowDecorViewModel<T>> mWindowDecorViewModelOptional;
+    private final Optional<WindowDecorViewModel> mWindowDecorViewModelOptional;
     /**
      * This constructor is used by downstream products.
      */
@@ -75,7 +69,7 @@ public class FullscreenTaskListener<T extends AutoCloseable>
             ShellTaskOrganizer shellTaskOrganizer,
             SyncTransactionQueue syncQueue,
             Optional<RecentTasksController> recentTasksOptional,
-            Optional<WindowDecorViewModel<T>> windowDecorViewModelOptional) {
+            Optional<WindowDecorViewModel> windowDecorViewModelOptional) {
         mShellTaskOrganizer = shellTaskOrganizer;
         mSyncQueue = syncQueue;
         mRecentTasksOptional = recentTasksOptional;
@@ -98,21 +92,21 @@ public class FullscreenTaskListener<T extends AutoCloseable>
         ProtoLog.v(ShellProtoLogGroup.WM_SHELL_TASK_ORG, "Fullscreen Task Appeared: #%d",
                 taskInfo.taskId);
         final Point positionInParent = taskInfo.positionInParent;
-        final State<T> state = new State();
+        final State state = new State();
         state.mLeash = leash;
         state.mTaskInfo = taskInfo;
         mTasks.put(taskInfo.taskId, state);
 
         if (Transitions.ENABLE_SHELL_TRANSITIONS) return;
         updateRecentsForVisibleFullscreenTask(taskInfo);
+        boolean createdWindowDecor = false;
         if (mWindowDecorViewModelOptional.isPresent()) {
             SurfaceControl.Transaction t = new SurfaceControl.Transaction();
-            state.mWindowDecoration =
+            createdWindowDecor = mWindowDecorViewModelOptional.get()
-                    mWindowDecorViewModelOptional.get().createWindowDecoration(taskInfo,
+                    .createWindowDecoration(taskInfo, leash, t, t);
-                            leash, t, t);
             t.apply();
         }
-        if (state.mWindowDecoration == null) {
+        if (!createdWindowDecor) {
             mSyncQueue.runInSync(t -> {
                 // Reset several properties back to fullscreen (PiP, for example, leaves all these
                 // properties in a bad state).
@@ -127,12 +121,11 @@ public class FullscreenTaskListener<T extends AutoCloseable>
 
     @Override
     public void onTaskInfoChanged(RunningTaskInfo taskInfo) {
-        final State<T> state = mTasks.get(taskInfo.taskId);
+        final State state = mTasks.get(taskInfo.taskId);
         final Point oldPositionInParent = state.mTaskInfo.positionInParent;
         state.mTaskInfo = taskInfo;
-        if (state.mWindowDecoration != null) {
+        if (mWindowDecorViewModelOptional.isPresent()) {
-            mWindowDecorViewModelOptional.get().onTaskInfoChanged(
+            mWindowDecorViewModelOptional.get().onTaskInfoChanged(state.mTaskInfo);
-                    state.mTaskInfo, state.mWindowDecoration);
         }
         if (Transitions.ENABLE_SHELL_TRANSITIONS) return;
         updateRecentsForVisibleFullscreenTask(taskInfo);
@@ -147,160 +140,13 @@ public class FullscreenTaskListener<T extends AutoCloseable>
 
     @Override
     public void onTaskVanished(ActivityManager.RunningTaskInfo taskInfo) {
-        final State<T> state = mTasks.get(taskInfo.taskId);
-        if (state == null) {
-            // This is possible if the transition happens before this method.
-            return;
-        }
         ProtoLog.v(ShellProtoLogGroup.WM_SHELL_TASK_ORG, "Fullscreen Task Vanished: #%d",
                 taskInfo.taskId);
         mTasks.remove(taskInfo.taskId);
 
-        if (Transitions.ENABLE_SHELL_TRANSITIONS) {
+        if (Transitions.ENABLE_SHELL_TRANSITIONS) return;
-            // Save window decorations of closing tasks so that we can hand them over to the
+        if (mWindowDecorViewModelOptional.isPresent()) {
-            // transition system if this method happens before the transition. In case where the
+            mWindowDecorViewModelOptional.get().destroyWindowDecoration(taskInfo);
-            // transition didn't happen, it'd be cleared when the next transition finished.
-            if (state.mWindowDecoration != null) {
-                mWindowDecorOfVanishedTasks.put(taskInfo.taskId, state.mWindowDecoration);
-            }
-            return;
-        }
-        releaseWindowDecor(state.mWindowDecoration);
-    }
-
-    /**
-     * Creates a window decoration for a transition.
-     *
-     * @param change the change of this task transition that needs to have the task layer as the
-     *               leash
-     * @return {@code true} if a decoration was actually created.
-     */
-    public boolean createWindowDecoration(TransitionInfo.Change change,
-            SurfaceControl.Transaction startT, SurfaceControl.Transaction finishT) {
-        final State<T> state = createOrUpdateTaskState(change.getTaskInfo(), change.getLeash());
-        if (!mWindowDecorViewModelOptional.isPresent()) return false;
-        if (state.mWindowDecoration != null) {
-            // Already has a decoration.
-            return false;
-        }
-        T newWindowDecor = mWindowDecorViewModelOptional.get().createWindowDecoration(
-                state.mTaskInfo, state.mLeash, startT, finishT);
-        if (newWindowDecor != null) {
-            state.mWindowDecoration = newWindowDecor;
-            return true;
-        }
-        return false;
-    }
-
-    /**
-     * Adopt the incoming window decoration and lets the window decoration prepare for a transition.
-     *
-     * @param change the change of this task transition that needs to have the task layer as the
-     *               leash
-     * @param startT the start transaction of this transition
-     * @param finishT the finish transaction of this transition
-     * @param windowDecor the window decoration to adopt
-     * @return {@code true} if it adopts the window decoration; {@code false} otherwise
-     */
-    public boolean adoptWindowDecoration(
-            TransitionInfo.Change change,
-            SurfaceControl.Transaction startT,
-            SurfaceControl.Transaction finishT,
-            @Nullable AutoCloseable windowDecor) {
-        if (!mWindowDecorViewModelOptional.isPresent()) {
-            return false;
-        }
-        final State<T> state = createOrUpdateTaskState(change.getTaskInfo(), change.getLeash());
-        state.mWindowDecoration = mWindowDecorViewModelOptional.get().adoptWindowDecoration(
-                windowDecor);
-        if (state.mWindowDecoration != null) {
-            mWindowDecorViewModelOptional.get().setupWindowDecorationForTransition(
-                    state.mTaskInfo, startT, finishT, state.mWindowDecoration);
-            return true;
-        } else {
-            T newWindowDecor = mWindowDecorViewModelOptional.get().createWindowDecoration(
-                    state.mTaskInfo, state.mLeash, startT, finishT);
-            if (newWindowDecor != null) {
-                state.mWindowDecoration = newWindowDecor;
-            }
-            return false;
-        }
-    }
-
-    /**
-     * Clear window decors of vanished tasks.
-     */
-    public void onTaskTransitionFinished() {
-        if (mWindowDecorOfVanishedTasks.size() == 0) {
-            return;
-        }
-        ProtoLog.v(ShellProtoLogGroup.WM_SHELL_TRANSITIONS,
-                "Clearing window decors of vanished tasks. There could be visual defects "
-                + "if any of them is used later in transitions.");
-        for (int i = 0; i < mWindowDecorOfVanishedTasks.size(); ++i) {
-            releaseWindowDecor(mWindowDecorOfVanishedTasks.valueAt(i));
-        }
-        mWindowDecorOfVanishedTasks.clear();
-    }
-
-    /**
-     * Gives out the ownership of the task's window decoration. The given task is leaving (of has
-     * left) this task listener. This is the transition system asking for the ownership.
-     *
-     * @param taskInfo the maximizing task
-     * @return the window decor of the maximizing task if any
-     */
-    public T giveWindowDecoration(
-            ActivityManager.RunningTaskInfo taskInfo,
-            SurfaceControl.Transaction startT,
-            SurfaceControl.Transaction finishT) {
-        T windowDecor;
-        final State<T> state = mTasks.get(taskInfo.taskId);
-        if (state != null) {
-            windowDecor = state.mWindowDecoration;
-            state.mWindowDecoration = null;
-        } else {
-            windowDecor =
-                    mWindowDecorOfVanishedTasks.removeReturnOld(taskInfo.taskId);
-        }
-        if (mWindowDecorViewModelOptional.isPresent() && windowDecor != null) {
-            mWindowDecorViewModelOptional.get().setupWindowDecorationForTransition(
-                    taskInfo, startT, finishT, windowDecor);
-        }
-
-        return windowDecor;
-    }
-
-    private State<T> createOrUpdateTaskState(ActivityManager.RunningTaskInfo taskInfo,
-            SurfaceControl leash) {
-        State<T> state = mTasks.get(taskInfo.taskId);
-        if (state != null) {
-            updateTaskInfo(taskInfo);
-            return state;
-        }
-
-        state = new State<T>();
-        state.mTaskInfo = taskInfo;
-        state.mLeash = leash;
-        mTasks.put(taskInfo.taskId, state);
-
-        return state;
-    }
-
-    private State<T> updateTaskInfo(ActivityManager.RunningTaskInfo taskInfo) {
-        final State<T> state = mTasks.get(taskInfo.taskId);
-        state.mTaskInfo = taskInfo;
-        return state;
-    }
-
-    private void releaseWindowDecor(T windowDecor) {
-        if (windowDecor == null) {
-            return;
-        }
-        try {
-            windowDecor.close();
-        } catch (Exception e) {
-            Log.e(TAG, "Failed to release window decoration.", e);
         }
     }
 
@@ -342,6 +188,4 @@ public class FullscreenTaskListener<T extends AutoCloseable>
     public String toString() {
         return TAG + ":" + taskListenerTypeToString(TASK_LISTENER_TYPE_FULLSCREEN);
     }
-
-
 }

libs/WindowManager/Shell/src/com/android/wm/shell/windowdecor/CaptionWindowDecorViewModel.java

@@ -26,6 +26,7 @@ import android.app.ActivityManager.RunningTaskInfo;
 import android.app.ActivityTaskManager;
 import android.content.Context;
 import android.os.Handler;
+import android.util.SparseArray;
 import android.view.Choreographer;
 import android.view.MotionEvent;
 import android.view.SurfaceControl;
@@ -46,7 +47,7 @@ import com.android.wm.shell.transition.Transitions;
  * View model for the window decoration with a caption and shadows. Works with
  * {@link CaptionWindowDecoration}.
  */
-public class CaptionWindowDecorViewModel implements WindowDecorViewModel<CaptionWindowDecoration> {
+public class CaptionWindowDecorViewModel implements WindowDecorViewModel {
     private final ActivityTaskManager mActivityTaskManager;
     private final ShellTaskOrganizer mTaskOrganizer;
     private final Context mContext;
@@ -57,6 +58,8 @@ public class CaptionWindowDecorViewModel implements WindowDecorViewModel<Caption
     private FreeformTaskTransitionStarter mTransitionStarter;
     private DesktopModeController mDesktopModeController;
 
+    private final SparseArray<CaptionWindowDecoration> mWindowDecorByTaskId = new SparseArray<>();
+
     public CaptionWindowDecorViewModel(
             Context context,
             Handler mainHandler,
@@ -81,12 +84,12 @@ public class CaptionWindowDecorViewModel implements WindowDecorViewModel<Caption
     }
 
     @Override
-    public CaptionWindowDecoration createWindowDecoration(
+    public boolean createWindowDecoration(
             ActivityManager.RunningTaskInfo taskInfo,
             SurfaceControl taskSurface,
             SurfaceControl.Transaction startT,
             SurfaceControl.Transaction finishT) {
-        if (!shouldShowWindowDecor(taskInfo)) return null;
+        if (!shouldShowWindowDecor(taskInfo)) return false;
         final CaptionWindowDecoration windowDecoration = new CaptionWindowDecoration(
                 mContext,
                 mDisplayController,
@@ -96,30 +99,24 @@ public class CaptionWindowDecorViewModel implements WindowDecorViewModel<Caption
                 mMainHandler,
                 mMainChoreographer,
                 mSyncQueue);
+        mWindowDecorByTaskId.put(taskInfo.taskId, windowDecoration);
+
         TaskPositioner taskPositioner = new TaskPositioner(mTaskOrganizer, windowDecoration);
         CaptionTouchEventListener touchEventListener =
                 new CaptionTouchEventListener(taskInfo, taskPositioner);
         windowDecoration.setCaptionListeners(touchEventListener, touchEventListener);
         windowDecoration.setDragResizeCallback(taskPositioner);
-        setupWindowDecorationForTransition(taskInfo, startT, finishT, windowDecoration);
+        setupWindowDecorationForTransition(taskInfo, startT, finishT);
         setupCaptionColor(taskInfo, windowDecoration);
-        return windowDecoration;
+        return true;
     }
 
     @Override
-    public CaptionWindowDecoration adoptWindowDecoration(AutoCloseable windowDecor) {
+    public void onTaskInfoChanged(RunningTaskInfo taskInfo) {
-        if (!(windowDecor instanceof CaptionWindowDecoration)) return null;
+        final CaptionWindowDecoration decoration = mWindowDecorByTaskId.get(taskInfo.taskId);
-        final CaptionWindowDecoration captionWindowDecor = (CaptionWindowDecoration) windowDecor;
+        if (decoration == null) return;
-        if (!shouldShowWindowDecor(captionWindowDecor.mTaskInfo)) {
-            return null;
-        }
-        return captionWindowDecor;
-    }
 
-    @Override
-    public void onTaskInfoChanged(RunningTaskInfo taskInfo, CaptionWindowDecoration decoration) {
         decoration.relayout(taskInfo);
-
         setupCaptionColor(taskInfo, decoration);
     }
 
@@ -132,11 +129,22 @@ public class CaptionWindowDecorViewModel implements WindowDecorViewModel<Caption
     public void setupWindowDecorationForTransition(
             RunningTaskInfo taskInfo,
             SurfaceControl.Transaction startT,
-            SurfaceControl.Transaction finishT,
+            SurfaceControl.Transaction finishT) {
-            CaptionWindowDecoration decoration) {
+        final CaptionWindowDecoration decoration = mWindowDecorByTaskId.get(taskInfo.taskId);
+        if (decoration == null) return;
+
         decoration.relayout(taskInfo, startT, finishT);
     }
 
+    @Override
+    public void destroyWindowDecoration(RunningTaskInfo taskInfo) {
+        final CaptionWindowDecoration decoration =
+                mWindowDecorByTaskId.removeReturnOld(taskInfo.taskId);
+        if (decoration == null) return;
+
+        decoration.close();
+    }
+
     private class CaptionTouchEventListener implements
             View.OnClickListener, View.OnTouchListener {
 

libs/WindowManager/Shell/src/com/android/wm/shell/windowdecor/WindowDecorViewModel.java

@@ -19,8 +19,6 @@ package com.android.wm.shell.windowdecor;
 import android.app.ActivityManager;
 import android.view.SurfaceControl;
 
-import androidx.annotation.Nullable;
-
 import com.android.wm.shell.freeform.FreeformTaskTransitionStarter;
 
 /**
@@ -28,10 +26,8 @@ import com.android.wm.shell.freeform.FreeformTaskTransitionStarter;
  * customize {@link WindowDecoration}. Its implementations are responsible to interpret user's
  * interactions with UI widgets in window decorations and send corresponding requests to system
  * servers.
- *
- * @param <T> The actual decoration type
  */
-public interface WindowDecorViewModel<T extends AutoCloseable> {
+public interface WindowDecorViewModel {
 
     /**
      * Sets the transition starter that starts freeform task transitions.
@@ -50,29 +46,19 @@ public interface WindowDecorViewModel<T extends AutoCloseable> {
      * @param finishT the finish transaction to restore states after the transition
      * @return the window decoration object
      */
-    @Nullable T createWindowDecoration(
+    boolean createWindowDecoration(
             ActivityManager.RunningTaskInfo taskInfo,
             SurfaceControl taskSurface,
             SurfaceControl.Transaction startT,
             SurfaceControl.Transaction finishT);
 
-    /**
-     * Adopts the window decoration if possible.
-     * May be {@code null} if a window decor is not needed or the given one is incompatible.
-     *
-     * @param windowDecor the potential window decoration to adopt
-     * @return the window decoration if it can be adopted, or {@code null} otherwise.
-     */
-    @Nullable T adoptWindowDecoration(@Nullable AutoCloseable windowDecor);
-
     /**
      * Notifies a task info update on the given task, with the window decoration created previously
      * for this task by {@link #createWindowDecoration}.
      *
      * @param taskInfo the new task info of the task
-     * @param windowDecoration the window decoration created for the task
      */
-    void onTaskInfoChanged(ActivityManager.RunningTaskInfo taskInfo, T windowDecoration);
+    void onTaskInfoChanged(ActivityManager.RunningTaskInfo taskInfo);
 
     /**
      * Notifies a transition is about to start about the given task to give the window decoration a
@@ -80,11 +66,16 @@ public interface WindowDecorViewModel<T extends AutoCloseable> {
      *
      * @param startT the start transaction to be applied before the transition
      * @param finishT the finish transaction to restore states after the transition
-     * @param windowDecoration the window decoration created for the task
      */
     void setupWindowDecorationForTransition(
             ActivityManager.RunningTaskInfo taskInfo,
             SurfaceControl.Transaction startT,
-            SurfaceControl.Transaction finishT,
+            SurfaceControl.Transaction finishT);
-            T windowDecoration);
+
+    /**
+     * Destroys the window decoration of the give task.
+     *
+     * @param taskInfo the info of the task
+     */
+    void destroyWindowDecoration(ActivityManager.RunningTaskInfo taskInfo);
 }

libs/WindowManager/Shell/tests/unittest/src/com/android/wm/shell/freeform/FreeformTaskTransitionObserverTest.java

@@ -17,17 +17,10 @@
 package com.android.wm.shell.freeform;
 
 import static android.app.WindowConfiguration.WINDOWING_MODE_FREEFORM;
-import static android.app.WindowConfiguration.WINDOWING_MODE_FULLSCREEN;
-import static android.view.WindowManager.TRANSIT_CHANGE;
 import static android.view.WindowManager.TRANSIT_CLOSE;
 import static android.view.WindowManager.TRANSIT_OPEN;
 
-import static com.android.wm.shell.transition.Transitions.TRANSIT_MAXIMIZE;
-import static com.android.wm.shell.transition.Transitions.TRANSIT_RESTORE_FROM_MAXIMIZE;
-
-import static org.mockito.Mockito.any;
 import static org.mockito.Mockito.doReturn;
-import static org.mockito.Mockito.eq;
 import static org.mockito.Mockito.mock;
 import static org.mockito.Mockito.never;
 import static org.mockito.Mockito.same;
@@ -44,9 +37,9 @@ import android.window.WindowContainerToken;
 
 import androidx.test.filters.SmallTest;
 
-import com.android.wm.shell.fullscreen.FullscreenTaskListener;
 import com.android.wm.shell.sysui.ShellInit;
 import com.android.wm.shell.transition.Transitions;
+import com.android.wm.shell.windowdecor.WindowDecorViewModel;
 
 import org.junit.Before;
 import org.junit.Test;
@@ -65,9 +58,7 @@ public class FreeformTaskTransitionObserverTest {
     @Mock
     private Transitions mTransitions;
     @Mock
-    private FullscreenTaskListener<?> mFullscreenTaskListener;
+    private WindowDecorViewModel mWindowDecorViewModel;
-    @Mock
-    private FreeformTaskListener<?> mFreeformTaskListener;
 
     private FreeformTaskTransitionObserver mTransitionObserver;
 
@@ -82,7 +73,7 @@ public class FreeformTaskTransitionObserverTest {
         doReturn(pm).when(context).getPackageManager();
 
         mTransitionObserver = new FreeformTaskTransitionObserver(
-                context, mShellInit, mTransitions, mFullscreenTaskListener, mFreeformTaskListener);
+                context, mShellInit, mTransitions, mWindowDecorViewModel);
         if (Transitions.ENABLE_SHELL_TRANSITIONS) {
             final ArgumentCaptor<Runnable> initRunnableCaptor = ArgumentCaptor.forClass(
                     Runnable.class);
@@ -112,11 +103,12 @@ public class FreeformTaskTransitionObserverTest {
         mTransitionObserver.onTransitionReady(transition, info, startT, finishT);
         mTransitionObserver.onTransitionStarting(transition);
 
-        verify(mFreeformTaskListener).createWindowDecoration(change, startT, finishT);
+        verify(mWindowDecorViewModel).createWindowDecoration(
+                change.getTaskInfo(), change.getLeash(), startT, finishT);
     }
 
     @Test
-    public void testObtainsWindowDecorOnCloseTransition_freeform() {
+    public void testPreparesWindowDecorOnCloseTransition_freeform() {
         final TransitionInfo.Change change =
                 createChange(TRANSIT_CLOSE, 1, WINDOWING_MODE_FREEFORM);
         final TransitionInfo info = new TransitionInfo(TRANSIT_CLOSE, 0);
@@ -128,7 +120,8 @@ public class FreeformTaskTransitionObserverTest {
         mTransitionObserver.onTransitionReady(transition, info, startT, finishT);
         mTransitionObserver.onTransitionStarting(transition);
 
-        verify(mFreeformTaskListener).giveWindowDecoration(change.getTaskInfo(), startT, finishT);
+        verify(mWindowDecorViewModel).setupWindowDecorationForTransition(
+                change.getTaskInfo(), startT, finishT);
     }
 
     @Test
@@ -138,17 +131,13 @@ public class FreeformTaskTransitionObserverTest {
         final TransitionInfo info = new TransitionInfo(TRANSIT_CLOSE, 0);
         info.addChange(change);
 
-        final AutoCloseable windowDecor = mock(AutoCloseable.class);
-        doReturn(windowDecor).when(mFreeformTaskListener).giveWindowDecoration(
-                eq(change.getTaskInfo()), any(), any());
-
         final IBinder transition = mock(IBinder.class);
         final SurfaceControl.Transaction startT = mock(SurfaceControl.Transaction.class);
         final SurfaceControl.Transaction finishT = mock(SurfaceControl.Transaction.class);
         mTransitionObserver.onTransitionReady(transition, info, startT, finishT);
         mTransitionObserver.onTransitionStarting(transition);
 
-        verify(windowDecor, never()).close();
+        verify(mWindowDecorViewModel, never()).destroyWindowDecoration(change.getTaskInfo());
     }
 
     @Test
@@ -159,8 +148,6 @@ public class FreeformTaskTransitionObserverTest {
         info.addChange(change);
 
         final AutoCloseable windowDecor = mock(AutoCloseable.class);
-        doReturn(windowDecor).when(mFreeformTaskListener).giveWindowDecoration(
-                eq(change.getTaskInfo()), any(), any());
 
         final IBinder transition = mock(IBinder.class);
         final SurfaceControl.Transaction startT = mock(SurfaceControl.Transaction.class);
@@ -169,7 +156,7 @@ public class FreeformTaskTransitionObserverTest {
         mTransitionObserver.onTransitionStarting(transition);
         mTransitionObserver.onTransitionFinished(transition, false);
 
-        verify(windowDecor).close();
+        verify(mWindowDecorViewModel).destroyWindowDecoration(change.getTaskInfo());
     }
 
     @Test
@@ -192,10 +179,6 @@ public class FreeformTaskTransitionObserverTest {
         final TransitionInfo info2 = new TransitionInfo(TRANSIT_CLOSE, 0);
         info2.addChange(change2);
 
-        final AutoCloseable windowDecor2 = mock(AutoCloseable.class);
-        doReturn(windowDecor2).when(mFreeformTaskListener).giveWindowDecoration(
-                eq(change2.getTaskInfo()), any(), any());
-
         final IBinder transition2 = mock(IBinder.class);
         final SurfaceControl.Transaction startT2 = mock(SurfaceControl.Transaction.class);
         final SurfaceControl.Transaction finishT2 = mock(SurfaceControl.Transaction.class);
@@ -204,7 +187,7 @@ public class FreeformTaskTransitionObserverTest {
 
         mTransitionObserver.onTransitionFinished(transition1, false);
 
-        verify(windowDecor2).close();
+        verify(mWindowDecorViewModel).destroyWindowDecoration(change2.getTaskInfo());
     }
 
     @Test
@@ -215,10 +198,6 @@ public class FreeformTaskTransitionObserverTest {
         final TransitionInfo info1 = new TransitionInfo(TRANSIT_CLOSE, 0);
         info1.addChange(change1);
 
-        final AutoCloseable windowDecor1 = mock(AutoCloseable.class);
-        doReturn(windowDecor1).when(mFreeformTaskListener).giveWindowDecoration(
-                eq(change1.getTaskInfo()), any(), any());
-
         final IBinder transition1 = mock(IBinder.class);
         final SurfaceControl.Transaction startT1 = mock(SurfaceControl.Transaction.class);
         final SurfaceControl.Transaction finishT1 = mock(SurfaceControl.Transaction.class);
@@ -231,10 +210,6 @@ public class FreeformTaskTransitionObserverTest {
         final TransitionInfo info2 = new TransitionInfo(TRANSIT_CLOSE, 0);
         info2.addChange(change2);
 
-        final AutoCloseable windowDecor2 = mock(AutoCloseable.class);
-        doReturn(windowDecor2).when(mFreeformTaskListener).giveWindowDecoration(
-                eq(change2.getTaskInfo()), any(), any());
-
         final IBinder transition2 = mock(IBinder.class);
         final SurfaceControl.Transaction startT2 = mock(SurfaceControl.Transaction.class);
         final SurfaceControl.Transaction finishT2 = mock(SurfaceControl.Transaction.class);
@@ -243,48 +218,8 @@ public class FreeformTaskTransitionObserverTest {
 
         mTransitionObserver.onTransitionFinished(transition1, false);
 
-        verify(windowDecor1).close();
+        verify(mWindowDecorViewModel).destroyWindowDecoration(change1.getTaskInfo());
-        verify(windowDecor2).close();
+        verify(mWindowDecorViewModel).destroyWindowDecoration(change2.getTaskInfo());
-    }
-
-    @Test
-    public void testTransfersWindowDecorOnMaximize() {
-        final TransitionInfo.Change change =
-                createChange(TRANSIT_CHANGE, 1, WINDOWING_MODE_FULLSCREEN);
-        final TransitionInfo info = new TransitionInfo(TRANSIT_MAXIMIZE, 0);
-        info.addChange(change);
-
-        final AutoCloseable windowDecor = mock(AutoCloseable.class);
-        doReturn(windowDecor).when(mFreeformTaskListener).giveWindowDecoration(
-                eq(change.getTaskInfo()), any(), any());
-
-        final IBinder transition = mock(IBinder.class);
-        final SurfaceControl.Transaction startT = mock(SurfaceControl.Transaction.class);
-        final SurfaceControl.Transaction finishT = mock(SurfaceControl.Transaction.class);
-        mTransitionObserver.onTransitionReady(transition, info, startT, finishT);
-        mTransitionObserver.onTransitionStarting(transition);
-
-        verify(mFreeformTaskListener).giveWindowDecoration(change.getTaskInfo(), startT, finishT);
-        verify(mFullscreenTaskListener).adoptWindowDecoration(
-                eq(change), same(startT), same(finishT), any());
-    }
-
-    @Test
-    public void testTransfersWindowDecorOnRestoreFromMaximize() {
-        final TransitionInfo.Change change =
-                createChange(TRANSIT_CHANGE, 1, WINDOWING_MODE_FREEFORM);
-        final TransitionInfo info = new TransitionInfo(TRANSIT_RESTORE_FROM_MAXIMIZE, 0);
-        info.addChange(change);
-
-        final IBinder transition = mock(IBinder.class);
-        final SurfaceControl.Transaction startT = mock(SurfaceControl.Transaction.class);
-        final SurfaceControl.Transaction finishT = mock(SurfaceControl.Transaction.class);
-        mTransitionObserver.onTransitionReady(transition, info, startT, finishT);
-        mTransitionObserver.onTransitionStarting(transition);
-
-        verify(mFullscreenTaskListener).giveWindowDecoration(change.getTaskInfo(), startT, finishT);
-        verify(mFreeformTaskListener).adoptWindowDecoration(
-                eq(change), same(startT), same(finishT), any());
     }
 
     private static TransitionInfo.Change createChange(int mode, int taskId, int windowingMode) {