Merge "Adding callback support for Entering/Exiting DesktopMode" into main

4 files changed, 108 insertions, 28 deletions

diff --git a/libs/WindowManager/Shell/src/com/android/wm/shell/desktopmode/DesktopTasksController.kt b/libs/WindowManager/Shell/src/com/android/wm/shell/desktopmode/DesktopTasksController.kt
index 8bad87480985..0a39076a8768 100644
--- a/libs/WindowManager/Shell/src/com/android/wm/shell/desktopmode/DesktopTasksController.kt
+++ b/libs/WindowManager/Shell/src/com/android/wm/shell/desktopmode/DesktopTasksController.kt
@@ -127,6 +127,10 @@ import java.util.Optional
 import java.util.concurrent.Executor
 import java.util.function.Consumer
 import com.android.wm.shell.desktopmode.DesktopModeEventLogger.Companion.ResizeTrigger
+import com.android.wm.shell.desktopmode.DragToDesktopTransitionHandler.Companion.DRAG_TO_DESKTOP_FINISH_ANIM_DURATION_MS
+import com.android.wm.shell.desktopmode.EnterDesktopTaskTransitionHandler.FREEFORM_ANIMATION_DURATION
+import com.android.wm.shell.desktopmode.ExitDesktopTaskTransitionHandler.FULLSCREEN_ANIMATION_DURATION
+
 /** Handles moving tasks in and out of desktop */
 class DesktopTasksController(
     private val context: Context,
@@ -195,6 +199,9 @@ class DesktopTasksController(
     @VisibleForTesting
     var taskbarDesktopTaskListener: TaskbarDesktopTaskListener? = null
 
+    @VisibleForTesting
+    var desktopModeEnterExitTransitionListener: DesktopModeEntryExitTransitionListener? = null
+
     /** Task id of the task currently being dragged from fullscreen/split. */
     val draggingTaskId
         get() = dragToDesktopTransitionHandler.draggingTaskId
@@ -380,6 +387,7 @@ class DesktopTasksController(
         )
         // TODO(343149901): Add DPI changes for task launch
         val transition = enterDesktopTaskTransitionHandler.moveToDesktop(wct, transitionSource)
+        desktopModeEnterExitTransitionListener?.onEnterDesktopModeTransitionStarted(FREEFORM_ANIMATION_DURATION)
         taskIdToMinimize?.let { addPendingMinimizeTransition(transition, it) }
         exitResult.asExit()?.runOnTransitionStart?.invoke(transition)
         return true
@@ -409,6 +417,7 @@ class DesktopTasksController(
         addMoveToDesktopChanges(wct, task)
 
         val transition = enterDesktopTaskTransitionHandler.moveToDesktop(wct, transitionSource)
+        desktopModeEnterExitTransitionListener?.onEnterDesktopModeTransitionStarted(FREEFORM_ANIMATION_DURATION)
         taskIdToMinimize?.let { addPendingMinimizeTransition(transition, it) }
         exitResult.asExit()?.runOnTransitionStart?.invoke(transition)
     }
@@ -450,6 +459,9 @@ class DesktopTasksController(
         val exitResult = desktopImmersiveController.exitImmersiveIfApplicable(
             wct, taskInfo.displayId)
         val transition = dragToDesktopTransitionHandler.finishDragToDesktopTransition(wct)
+        desktopModeEnterExitTransitionListener?.onEnterDesktopModeTransitionStarted(
+            DRAG_TO_DESKTOP_FINISH_ANIM_DURATION_MS.toInt()
+        )
         transition?.let {
             taskIdToMinimize?.let { taskId -> addPendingMinimizeTransition(it, taskId) }
             exitResult.asExit()?.runOnTransitionStart?.invoke(transition)
@@ -485,9 +497,7 @@ class DesktopTasksController(
     ): ((IBinder) -> Unit)? {
         val taskId = taskInfo.taskId
         desktopTilingDecorViewModel.removeTaskIfTiled(displayId, taskId)
-        if (taskRepository.isOnlyVisibleNonClosingTask(taskId)) {
-            removeWallpaperActivity(wct)
-        }
+        performDesktopExitCleanupIfNeeded(taskId, wct)
         taskRepository.addClosingTask(displayId, taskId)
         taskbarDesktopTaskListener?.onTaskbarCornerRoundingUpdate(
             doesAnyTaskRequireTaskbarRounding(
@@ -503,11 +513,7 @@ class DesktopTasksController(
         val taskId = taskInfo.taskId
         val displayId = taskInfo.displayId
         val wct = WindowContainerTransaction()
-        if (taskRepository.isOnlyVisibleNonClosingTask(taskId)) {
-            // Perform clean up of the desktop wallpaper activity if the minimized window task is
-            // the last active task.
-            removeWallpaperActivity(wct)
-        }
+        performDesktopExitCleanupIfNeeded(taskId, wct)
         // Notify immersive handler as it might need to exit immersive state.
         val exitResult = desktopImmersiveController.exitImmersiveIfApplicable(wct, taskInfo)
 
@@ -576,6 +582,11 @@ class DesktopTasksController(
                 position,
                 mOnAnimationFinishedCallback
             )
+
+        // handles case where we are moving to full screen without closing all DW tasks.
+        if (!taskRepository.isOnlyVisibleNonClosingTask(task.taskId)) {
+            desktopModeEnterExitTransitionListener?.onExitDesktopModeTransitionStarted(FULLSCREEN_ANIMATION_DURATION)
+        }
     }
 
     /**
@@ -1226,6 +1237,21 @@ class DesktopTasksController(
         }
     }
 
+    /**
+     * Remove wallpaper activity if task provided is last task and wallpaper activity token is not
+     * null
+     */
+    private fun performDesktopExitCleanupIfNeeded(taskId: Int, wct: WindowContainerTransaction) {
+        if (!taskRepository.isOnlyVisibleNonClosingTask(taskId)) {
+            return
+        }
+        desktopModeEnterExitTransitionListener?.onExitDesktopModeTransitionStarted(FULLSCREEN_ANIMATION_DURATION)
+        if (taskRepository.wallpaperActivityToken != null) {
+            removeWallpaperActivity(wct)
+        }
+    }
+
+
     fun releaseVisualIndicator() {
         val t = SurfaceControl.Transaction()
         visualIndicator?.releaseVisualIndicator(t)
@@ -1662,12 +1688,7 @@ class DesktopTasksController(
             return null
 
         val wct = WindowContainerTransaction()
-        if (taskRepository.isOnlyVisibleNonClosingTask(task.taskId)
-            && taskRepository.wallpaperActivityToken != null
-        ) {
-            // Remove wallpaper activity when the last active task is removed
-            removeWallpaperActivity(wct)
-        }
+        performDesktopExitCleanupIfNeeded(task.taskId, wct)
 
         if (!DesktopModeFlags.ENABLE_DESKTOP_WINDOWING_BACK_NAVIGATION.isTrue()) {
             taskRepository.addClosingTask(task.displayId, task.taskId)
@@ -1758,10 +1779,8 @@ class DesktopTasksController(
         if (useDesktopOverrideDensity()) {
             wct.setDensityDpi(taskInfo.token, getDefaultDensityDpi())
         }
-        if (taskRepository.isOnlyVisibleNonClosingTask(taskInfo.taskId)) {
-            // Remove wallpaper activity when leaving desktop mode
-            removeWallpaperActivity(wct)
-        }
+
+        performDesktopExitCleanupIfNeeded(taskInfo.taskId, wct)
     }
 
     private fun cascadeWindow(bounds: Rect, displayLayout: DisplayLayout, displayId: Int) {
@@ -1790,10 +1809,8 @@ class DesktopTasksController(
         // The task's density may have been overridden in freeform; revert it here as we don't
         // want it overridden in multi-window.
         wct.setDensityDpi(taskInfo.token, getDefaultDensityDpi())
-        if (taskRepository.isOnlyVisibleNonClosingTask(taskInfo.taskId)) {
-            // Remove wallpaper activity when leaving desktop mode
-            removeWallpaperActivity(wct)
-        }
+
+        performDesktopExitCleanupIfNeeded(taskInfo.taskId, wct)
     }
 
     /** Returns the ID of the Task that will be minimized, or null if no task will be minimized. */
@@ -2331,7 +2348,7 @@ class DesktopTasksController(
                 }
             }
 
-        private val mTaskbarDesktopTaskListener: TaskbarDesktopTaskListener =
+        private val taskbarDesktopTaskListener: TaskbarDesktopTaskListener =
                 object : TaskbarDesktopTaskListener {
                     override fun onTaskbarCornerRoundingUpdate(
                         hasTasksRequiringTaskbarRounding: Boolean) {
@@ -2348,6 +2365,27 @@ class DesktopTasksController(
                     }
                 }
 
+        private val desktopModeEntryExitTransitionListener: DesktopModeEntryExitTransitionListener =
+            object : DesktopModeEntryExitTransitionListener {
+                override fun onEnterDesktopModeTransitionStarted(transitionDuration: Int) {
+                    ProtoLog.v(
+                        WM_SHELL_DESKTOP_MODE,
+                        "IDesktopModeImpl: onEnterDesktopModeTransitionStarted transitionTime=%s",
+                        transitionDuration
+                    )
+                    remoteListener.call { l -> l.onEnterDesktopModeTransitionStarted(transitionDuration) }
+                }
+
+                override fun onExitDesktopModeTransitionStarted(transitionDuration: Int) {
+                    ProtoLog.v(
+                        WM_SHELL_DESKTOP_MODE,
+                        "IDesktopModeImpl: onExitDesktopModeTransitionStarted transitionTime=%s",
+                        transitionDuration
+                    )
+                    remoteListener.call { l -> l.onExitDesktopModeTransitionStarted(transitionDuration) }
+                }
+            }
+
         init {
             remoteListener =
                 SingleInstanceRemoteListener<DesktopTasksController, IDesktopTaskListener>(
@@ -2355,13 +2393,16 @@ class DesktopTasksController(
                     { c ->
                         run {
                             c.taskRepository.addVisibleTasksListener(listener, c.mainExecutor)
-                            c.taskbarDesktopTaskListener = mTaskbarDesktopTaskListener
+                            c.taskbarDesktopTaskListener = taskbarDesktopTaskListener
+                            c.desktopModeEnterExitTransitionListener =
+                                desktopModeEntryExitTransitionListener
                         }
                     },
                     { c ->
                         run {
                             c.taskRepository.removeVisibleTasksListener(listener)
                             c.taskbarDesktopTaskListener = null
+                            c.desktopModeEnterExitTransitionListener = null
                         }
                     }
                 )
@@ -2468,6 +2509,15 @@ class DesktopTasksController(
         fun onTaskbarCornerRoundingUpdate(hasTasksRequiringTaskbarRounding: Boolean)
     }
 
+    /** Defines interface for entering and exiting desktop windowing mode. */
+    interface DesktopModeEntryExitTransitionListener {
+        /** [transitionDuration] time it takes to run enter desktop mode transition */
+        fun onEnterDesktopModeTransitionStarted(transitionDuration: Int)
+
+        /** [transitionDuration] time it takes to run exit desktop mode transition */
+        fun onExitDesktopModeTransitionStarted(transitionDuration: Int)
+    }
+
     /** The positions on a screen that a task can snap to. */
     enum class SnapPosition {
         RIGHT,
diff --git a/libs/WindowManager/Shell/src/com/android/wm/shell/desktopmode/ExitDesktopTaskTransitionHandler.java b/libs/WindowManager/Shell/src/com/android/wm/shell/desktopmode/ExitDesktopTaskTransitionHandler.java
index d537da802efd..b902bb4394b5 100644
--- a/libs/WindowManager/Shell/src/com/android/wm/shell/desktopmode/ExitDesktopTaskTransitionHandler.java
+++ b/libs/WindowManager/Shell/src/com/android/wm/shell/desktopmode/ExitDesktopTaskTransitionHandler.java
@@ -60,8 +60,7 @@ import java.util.function.Supplier;
  * entering and exiting freeform.
  */
 public class ExitDesktopTaskTransitionHandler implements Transitions.TransitionHandler {
-    @VisibleForTesting
-    static final int FULLSCREEN_ANIMATION_DURATION = 336;
+    public static final int FULLSCREEN_ANIMATION_DURATION = 336;
 
     private final Context mContext;
     private final Transitions mTransitions;
diff --git a/libs/WindowManager/Shell/src/com/android/wm/shell/desktopmode/IDesktopTaskListener.aidl b/libs/WindowManager/Shell/src/com/android/wm/shell/desktopmode/IDesktopTaskListener.aidl
index c2acb87222d1..6002a4dfe0d9 100644
--- a/libs/WindowManager/Shell/src/com/android/wm/shell/desktopmode/IDesktopTaskListener.aidl
+++ b/libs/WindowManager/Shell/src/com/android/wm/shell/desktopmode/IDesktopTaskListener.aidl
@@ -33,4 +33,10 @@ interface IDesktopTaskListener {
      * [hasTasksRequiringTaskbarRounding] is true.
      */
     oneway void onTaskbarCornerRoundingUpdate(boolean hasTasksRequiringTaskbarRounding);
+
+    /** Entering desktop mode transition is started, send the signal with transition duration. */
+    oneway void onEnterDesktopModeTransitionStarted(int transitionDuration);
+
+    /** Exiting desktop mode transition is started, send the signal with transition duration. */
+    oneway void onExitDesktopModeTransitionStarted(int transitionDuration);
 }
\ No newline at end of file
diff --git a/libs/WindowManager/Shell/tests/unittest/src/com/android/wm/shell/desktopmode/DesktopTasksControllerTest.kt b/libs/WindowManager/Shell/tests/unittest/src/com/android/wm/shell/desktopmode/DesktopTasksControllerTest.kt
index 93999476316a..936835c34c04 100644
--- a/libs/WindowManager/Shell/tests/unittest/src/com/android/wm/shell/desktopmode/DesktopTasksControllerTest.kt
+++ b/libs/WindowManager/Shell/tests/unittest/src/com/android/wm/shell/desktopmode/DesktopTasksControllerTest.kt
@@ -95,12 +95,15 @@ import com.android.wm.shell.common.ShellExecutor
 import com.android.wm.shell.common.SyncTransactionQueue
 import com.android.wm.shell.desktopmode.DesktopImmersiveController.ExitResult
 import com.android.wm.shell.desktopmode.DesktopModeEventLogger.Companion.ResizeTrigger
+import com.android.wm.shell.desktopmode.DesktopTasksController.DesktopModeEntryExitTransitionListener
 import com.android.wm.shell.desktopmode.DesktopTasksController.SnapPosition
 import com.android.wm.shell.desktopmode.DesktopTasksController.TaskbarDesktopTaskListener
 import com.android.wm.shell.desktopmode.DesktopTestHelpers.Companion.createFreeformTask
 import com.android.wm.shell.desktopmode.DesktopTestHelpers.Companion.createFullscreenTask
 import com.android.wm.shell.desktopmode.DesktopTestHelpers.Companion.createHomeTask
 import com.android.wm.shell.desktopmode.DesktopTestHelpers.Companion.createSplitScreenTask
+import com.android.wm.shell.desktopmode.EnterDesktopTaskTransitionHandler.FREEFORM_ANIMATION_DURATION
+import com.android.wm.shell.desktopmode.ExitDesktopTaskTransitionHandler.FULLSCREEN_ANIMATION_DURATION
 import com.android.wm.shell.desktopmode.minimize.DesktopWindowLimitRemoteHandler
 import com.android.wm.shell.desktopmode.persistence.Desktop
 import com.android.wm.shell.desktopmode.persistence.DesktopPersistentRepository
@@ -223,6 +226,8 @@ class DesktopTasksControllerTest : ShellTestCase() {
   @Mock
   private lateinit var desktopWindowDecoration: DesktopModeWindowDecoration
   @Mock private lateinit var resources: Resources
+  @Mock
+  lateinit var desktopModeEnterExitTransitionListener: DesktopModeEntryExitTransitionListener
   private lateinit var controller: DesktopTasksController
   private lateinit var shellInit: ShellInit
   private lateinit var taskRepository: DesktopRepository
@@ -294,6 +299,7 @@ class DesktopTasksControllerTest : ShellTestCase() {
     controller = createController()
     controller.setSplitScreenController(splitScreenController)
     controller.freeformTaskTransitionStarter = freeformTaskTransitionStarter
+    controller.desktopModeEnterExitTransitionListener = desktopModeEnterExitTransitionListener
 
     shellInit.init()
 
@@ -1054,6 +1060,7 @@ class DesktopTasksControllerTest : ShellTestCase() {
     controller.moveRunningTaskToDesktop(task, transitionSource = UNKNOWN)
     val wct = getLatestEnterDesktopWct()
     assertThat(wct.changes[task.token.asBinder()]?.windowingMode).isEqualTo(WINDOWING_MODE_FREEFORM)
+    verify(desktopModeEnterExitTransitionListener).onEnterDesktopModeTransitionStarted(FREEFORM_ANIMATION_DURATION)
   }
 
   @Test
@@ -1065,12 +1072,14 @@ class DesktopTasksControllerTest : ShellTestCase() {
     val wct = getLatestEnterDesktopWct()
     assertThat(wct.changes[task.token.asBinder()]?.windowingMode)
         .isEqualTo(WINDOWING_MODE_UNDEFINED)
+    verify(desktopModeEnterExitTransitionListener).onEnterDesktopModeTransitionStarted(FREEFORM_ANIMATION_DURATION)
   }
 
   @Test
   fun moveTaskToDesktop_nonExistentTask_doesNothing() {
     controller.moveTaskToDesktop(999, transitionSource = UNKNOWN)
     verifyEnterDesktopWCTNotExecuted()
+    verify(desktopModeEnterExitTransitionListener, times(0)).onEnterDesktopModeTransitionStarted(anyInt())
   }
 
   @Test
@@ -1115,9 +1124,9 @@ class DesktopTasksControllerTest : ShellTestCase() {
       }
 
     controller.moveRunningTaskToDesktop(task, transitionSource = UNKNOWN)
-
     val wct = getLatestEnterDesktopWct()
     assertThat(wct.changes[task.token.asBinder()]?.windowingMode).isEqualTo(WINDOWING_MODE_FREEFORM)
+    verify(desktopModeEnterExitTransitionListener).onEnterDesktopModeTransitionStarted(FREEFORM_ANIMATION_DURATION)
   }
 
   @Test
@@ -1132,6 +1141,9 @@ class DesktopTasksControllerTest : ShellTestCase() {
 
     controller.moveRunningTaskToDesktop(task, transitionSource = UNKNOWN)
     verifyEnterDesktopWCTNotExecuted()
+    verify(desktopModeEnterExitTransitionListener, times(0)).onEnterDesktopModeTransitionStarted(
+      FREEFORM_ANIMATION_DURATION
+    )
   }
 
   @Test
@@ -1178,6 +1190,7 @@ class DesktopTasksControllerTest : ShellTestCase() {
 
     val wct = getLatestEnterDesktopWct()
     assertThat(wct.changes[task.token.asBinder()]?.windowingMode).isEqualTo(WINDOWING_MODE_FREEFORM)
+    verify(desktopModeEnterExitTransitionListener).onEnterDesktopModeTransitionStarted(FREEFORM_ANIMATION_DURATION)
   }
 
   @Test
@@ -1197,6 +1210,7 @@ class DesktopTasksControllerTest : ShellTestCase() {
       assertThat(changes[fullscreenTask.token.asBinder()]?.windowingMode)
           .isEqualTo(WINDOWING_MODE_FREEFORM)
     }
+    verify(desktopModeEnterExitTransitionListener).onEnterDesktopModeTransitionStarted(FREEFORM_ANIMATION_DURATION)
   }
 
   @Test
@@ -1217,6 +1231,7 @@ class DesktopTasksControllerTest : ShellTestCase() {
       assertThat(changes[fullscreenTask.token.asBinder()]?.windowingMode)
           .isEqualTo(WINDOWING_MODE_FREEFORM)
     }
+    verify(desktopModeEnterExitTransitionListener).onEnterDesktopModeTransitionStarted(FREEFORM_ANIMATION_DURATION)
   }
 
   @Test
@@ -1238,6 +1253,7 @@ class DesktopTasksControllerTest : ShellTestCase() {
       assertThat(hierarchyOps.map { it.container })
           .doesNotContain(freeformTaskSecond.token.asBinder())
     }
+    verify(desktopModeEnterExitTransitionListener).onEnterDesktopModeTransitionStarted(FREEFORM_ANIMATION_DURATION)
   }
 
   @Test
@@ -1246,6 +1262,7 @@ class DesktopTasksControllerTest : ShellTestCase() {
     controller.moveRunningTaskToDesktop(task, transitionSource = UNKNOWN)
     val wct = getLatestEnterDesktopWct()
     assertThat(wct.changes[task.token.asBinder()]?.windowingMode).isEqualTo(WINDOWING_MODE_FREEFORM)
+    verify(desktopModeEnterExitTransitionListener).onEnterDesktopModeTransitionStarted(FREEFORM_ANIMATION_DURATION)
     verify(splitScreenController)
         .prepareExitSplitScreen(any(), anyInt(), eq(SplitScreenController.EXIT_REASON_DESKTOP_MODE))
   }
@@ -1256,6 +1273,7 @@ class DesktopTasksControllerTest : ShellTestCase() {
     controller.moveRunningTaskToDesktop(task, transitionSource = UNKNOWN)
     val wct = getLatestEnterDesktopWct()
     assertThat(wct.changes[task.token.asBinder()]?.windowingMode).isEqualTo(WINDOWING_MODE_FREEFORM)
+    verify(desktopModeEnterExitTransitionListener).onEnterDesktopModeTransitionStarted(FREEFORM_ANIMATION_DURATION)
     verify(splitScreenController, never())
         .prepareExitSplitScreen(any(), anyInt(), eq(SplitScreenController.EXIT_REASON_DESKTOP_MODE))
   }
@@ -1270,6 +1288,7 @@ class DesktopTasksControllerTest : ShellTestCase() {
     controller.moveRunningTaskToDesktop(newTask, transitionSource = UNKNOWN)
 
     val wct = getLatestEnterDesktopWct()
+    verify(desktopModeEnterExitTransitionListener).onEnterDesktopModeTransitionStarted(FREEFORM_ANIMATION_DURATION)
     assertThat(wct.hierarchyOps.size).isEqualTo(MAX_TASK_LIMIT + 1) // visible tasks + home
     wct.assertReorderAt(0, homeTask)
     wct.assertReorderSequenceInRange(
@@ -1288,6 +1307,7 @@ class DesktopTasksControllerTest : ShellTestCase() {
     controller.moveRunningTaskToDesktop(newTask, transitionSource = UNKNOWN)
 
     val wct = getLatestEnterDesktopWct()
+    verify(desktopModeEnterExitTransitionListener).onEnterDesktopModeTransitionStarted(FREEFORM_ANIMATION_DURATION)
     assertThat(wct.hierarchyOps.size).isEqualTo(MAX_TASK_LIMIT + 2) // tasks + home + wallpaper
     // Move home to front
     wct.assertReorderAt(0, homeTask)
@@ -1307,6 +1327,7 @@ class DesktopTasksControllerTest : ShellTestCase() {
     tda.configuration.windowConfiguration.windowingMode = WINDOWING_MODE_FULLSCREEN
     controller.moveToFullscreen(task.taskId, transitionSource = UNKNOWN)
     val wct = getLatestExitDesktopWct()
+    verify(desktopModeEnterExitTransitionListener, times(1)).onExitDesktopModeTransitionStarted(FULLSCREEN_ANIMATION_DURATION)
     assertThat(wct.changes[task.token.asBinder()]?.windowingMode)
         .isEqualTo(WINDOWING_MODE_UNDEFINED)
   }
@@ -1324,6 +1345,7 @@ class DesktopTasksControllerTest : ShellTestCase() {
 
     val wct = getLatestExitDesktopWct()
     val taskChange = assertNotNull(wct.changes[task.token.asBinder()])
+    verify(desktopModeEnterExitTransitionListener).onExitDesktopModeTransitionStarted(FULLSCREEN_ANIMATION_DURATION)
     assertThat(taskChange.windowingMode).isEqualTo(WINDOWING_MODE_UNDEFINED)
     // Removes wallpaper activity when leaving desktop
     wct.assertRemoveAt(index = 0, wallpaperToken)
@@ -1338,6 +1360,7 @@ class DesktopTasksControllerTest : ShellTestCase() {
     val wct = getLatestExitDesktopWct()
     assertThat(wct.changes[task.token.asBinder()]?.windowingMode)
         .isEqualTo(WINDOWING_MODE_FULLSCREEN)
+    verify(desktopModeEnterExitTransitionListener).onExitDesktopModeTransitionStarted(FULLSCREEN_ANIMATION_DURATION)
   }
 
   @Test
@@ -1354,6 +1377,7 @@ class DesktopTasksControllerTest : ShellTestCase() {
     val wct = getLatestExitDesktopWct()
     val taskChange = assertNotNull(wct.changes[task.token.asBinder()])
     assertThat(taskChange.windowingMode).isEqualTo(WINDOWING_MODE_FULLSCREEN)
+    verify(desktopModeEnterExitTransitionListener).onExitDesktopModeTransitionStarted(FULLSCREEN_ANIMATION_DURATION)
     // Removes wallpaper activity when leaving desktop
     wct.assertRemoveAt(index = 0, wallpaperToken)
   }
@@ -1374,6 +1398,7 @@ class DesktopTasksControllerTest : ShellTestCase() {
     val wct = getLatestExitDesktopWct()
     val task1Change = assertNotNull(wct.changes[task1.token.asBinder()])
     assertThat(task1Change.windowingMode).isEqualTo(WINDOWING_MODE_UNDEFINED)
+    verify(desktopModeEnterExitTransitionListener).onExitDesktopModeTransitionStarted(FULLSCREEN_ANIMATION_DURATION)
     // Does not remove wallpaper activity, as desktop still has a visible desktop task
     assertThat(wct.hierarchyOps).isEmpty()
   }
@@ -1388,13 +1413,13 @@ class DesktopTasksControllerTest : ShellTestCase() {
   fun moveToFullscreen_secondDisplayTaskHasFreeform_secondDisplayNotAffected() {
     val taskDefaultDisplay = setUpFreeformTask(displayId = DEFAULT_DISPLAY)
     val taskSecondDisplay = setUpFreeformTask(displayId = SECOND_DISPLAY)
-
     controller.moveToFullscreen(taskDefaultDisplay.taskId, transitionSource = UNKNOWN)
 
     with(getLatestExitDesktopWct()) {
       assertThat(changes.keys).contains(taskDefaultDisplay.token.asBinder())
       assertThat(changes.keys).doesNotContain(taskSecondDisplay.token.asBinder())
     }
+    verify(desktopModeEnterExitTransitionListener).onExitDesktopModeTransitionStarted(FULLSCREEN_ANIMATION_DURATION)
   }
 
   @Test