Flag desktop stashing behavior

Turn off desktop stashing by default. When going home from desktop, user
exits the desktop and subsequent app launches will be to fullscreen.
Keep the stashing behavior behind a flag so that it can be enabled if
desired.

Bug: 292109910
Test: atest DesktopTasksControllerTest
Change-Id: I566c33c4787542da70bcc052d3c3f2788ea90c4b

3 files changed, 34 insertions, 8 deletions

diff --git a/libs/WindowManager/Shell/src/com/android/wm/shell/desktopmode/DesktopModeStatus.java b/libs/WindowManager/Shell/src/com/android/wm/shell/desktopmode/DesktopModeStatus.java
index 76ca68bbfa75..517f9f2aba27 100644
--- a/libs/WindowManager/Shell/src/com/android/wm/shell/desktopmode/DesktopModeStatus.java
+++ b/libs/WindowManager/Shell/src/com/android/wm/shell/desktopmode/DesktopModeStatus.java
@@ -54,6 +54,15 @@ public class DesktopModeStatus {
     public static final boolean IS_DISPLAY_CHANGE_ENABLED = SystemProperties.getBoolean(
             "persist.wm.debug.desktop_change_display", false);
 
+
+    /**
+     * Flag to indicate that desktop stashing is enabled.
+     * When enabled, swiping home from desktop stashes the open apps. Next app that launches,
+     * will be added to the desktop.
+     */
+    private static final boolean IS_STASHING_ENABLED = SystemProperties.getBoolean(
+            "persist.wm.debug.desktop_stashing", false);
+
     /**
      * Return {@code true} if desktop mode support is enabled
      */
@@ -84,6 +93,13 @@ public class DesktopModeStatus {
     }
 
     /**
+     * Return {@code true} if desktop task stashing is enabled when going home.
+     * Allows users to use home screen to add tasks to desktop.
+     */
+    public static boolean isStashingEnabled() {
+        return IS_STASHING_ENABLED;
+    }
+    /**
      * Check if desktop mode is active
      *
      * @return {@code true} if active
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 f8d7b6bc3aad..07419f8365a2 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
@@ -150,20 +150,24 @@ class DesktopTasksController(
      * back to front during the launch.
      */
     fun stashDesktopApps(displayId: Int) {
-        KtProtoLog.v(WM_SHELL_DESKTOP_MODE, "DesktopTasksController: stashDesktopApps")
-        desktopModeTaskRepository.setStashed(displayId, true)
+        if (DesktopModeStatus.isStashingEnabled()) {
+            KtProtoLog.v(WM_SHELL_DESKTOP_MODE, "DesktopTasksController: stashDesktopApps")
+            desktopModeTaskRepository.setStashed(displayId, true)
+        }
     }
 
     /**
      * Clear the stashed state for the given display
      */
     fun hideStashedDesktopApps(displayId: Int) {
-        KtProtoLog.v(
-                WM_SHELL_DESKTOP_MODE,
-                "DesktopTasksController: hideStashedApps displayId=%d",
-                displayId
-        )
-        desktopModeTaskRepository.setStashed(displayId, false)
+        if (DesktopModeStatus.isStashingEnabled()) {
+            KtProtoLog.v(
+                    WM_SHELL_DESKTOP_MODE,
+                    "DesktopTasksController: hideStashedApps displayId=%d",
+                    displayId
+            )
+            desktopModeTaskRepository.setStashed(displayId, false)
+        }
     }
 
     /** Get number of tasks that are marked as visible */
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 1477cf7415cf..11d7f15b34ca 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
@@ -498,6 +498,7 @@ class DesktopTasksControllerTest : ShellTestCase() {
     @Test
     fun handleRequest_fullscreenTask_desktopStashed_returnWCTWithAllAppsBroughtToFront() {
         assumeTrue(ENABLE_SHELL_TRANSITIONS)
+        whenever(DesktopModeStatus.isStashingEnabled()).thenReturn(true)
 
         val stashedFreeformTask = setUpFreeformTask(DEFAULT_DISPLAY)
         markTaskHidden(stashedFreeformTask)
@@ -569,6 +570,7 @@ class DesktopTasksControllerTest : ShellTestCase() {
     @Test
     fun handleRequest_freeformTask_desktopStashed_returnWCTWithAllAppsBroughtToFront() {
         assumeTrue(ENABLE_SHELL_TRANSITIONS)
+        whenever(DesktopModeStatus.isStashingEnabled()).thenReturn(true)
 
         val stashedFreeformTask = setUpFreeformTask(DEFAULT_DISPLAY)
         markTaskHidden(stashedFreeformTask)
@@ -626,6 +628,8 @@ class DesktopTasksControllerTest : ShellTestCase() {
 
     @Test
     fun stashDesktopApps_stateUpdates() {
+        whenever(DesktopModeStatus.isStashingEnabled()).thenReturn(true)
+
         controller.stashDesktopApps(DEFAULT_DISPLAY)
 
         assertThat(desktopModeTaskRepository.isStashed(DEFAULT_DISPLAY)).isTrue()
@@ -634,6 +638,8 @@ class DesktopTasksControllerTest : ShellTestCase() {
 
     @Test
     fun hideStashedDesktopApps_stateUpdates() {
+        whenever(DesktopModeStatus.isStashingEnabled()).thenReturn(true)
+
         desktopModeTaskRepository.setStashed(DEFAULT_DISPLAY, true)
         desktopModeTaskRepository.setStashed(SECOND_DISPLAY, true)
         controller.hideStashedDesktopApps(DEFAULT_DISPLAY)