From 55e648f6820eb616ddf449baa88ac087270d40d0 Mon Sep 17 00:00:00 2001
From: Fengjiang Li <fengjial@google.com>
Date: Tue, 18 Apr 2023 11:16:16 -0700
Subject: [PATCH] Fix NPE of predictive back in TaskbarAllAppsSlideInView

Fix: 278597104
Test: tested predictive back in taskbar all apps view
Change-Id: I32e3cba5d26b3d05e9b7af584598bf04e512a684
---
 .../allapps/TaskbarAllAppsSlideInView.java    | 27 ++++++++++++-------
 .../launcher3/config/FeatureFlags.java        |  2 +-
 2 files changed, 18 insertions(+), 11 deletions(-)

diff --git a/quickstep/src/com/android/launcher3/taskbar/allapps/TaskbarAllAppsSlideInView.java b/quickstep/src/com/android/launcher3/taskbar/allapps/TaskbarAllAppsSlideInView.java
index d69769a8a4..f0d28dfd05 100644
--- a/quickstep/src/com/android/launcher3/taskbar/allapps/TaskbarAllAppsSlideInView.java
+++ b/quickstep/src/com/android/launcher3/taskbar/allapps/TaskbarAllAppsSlideInView.java
@@ -71,13 +71,6 @@ public class TaskbarAllAppsSlideInView extends AbstractSlideInView<TaskbarOverla
         } else {
             mTranslationShift = TRANSLATION_SHIFT_OPENED;
         }
-
-        if (FeatureFlags.ENABLE_BACK_SWIPE_LAUNCHER_ANIMATION.get()) {
-            mAppsView.getAppsRecyclerViewContainer().setOutlineProvider(mViewOutlineProvider);
-            mAppsView.getAppsRecyclerViewContainer().setClipToOutline(true);
-            findOnBackInvokedDispatcher().registerOnBackInvokedCallback(
-                    OnBackInvokedDispatcher.PRIORITY_DEFAULT, this);
-        }
     }
 
     /** The apps container inside this view. */
@@ -88,9 +81,6 @@ public class TaskbarAllAppsSlideInView extends AbstractSlideInView<TaskbarOverla
     @Override
     protected void handleClose(boolean animate) {
         handleClose(animate, mAllAppsCallbacks.getCloseDuration());
-        if (FeatureFlags.ENABLE_BACK_SWIPE_LAUNCHER_ANIMATION.get()) {
-            findOnBackInvokedDispatcher().unregisterOnBackInvokedCallback(this);
-        }
     }
 
     @Override
@@ -121,12 +111,29 @@ public class TaskbarAllAppsSlideInView extends AbstractSlideInView<TaskbarOverla
     protected void onAttachedToWindow() {
         super.onAttachedToWindow();
         mActivityContext.addOnDeviceProfileChangeListener(this);
+        if (FeatureFlags.ENABLE_BACK_SWIPE_LAUNCHER_ANIMATION.get()) {
+            mAppsView.getAppsRecyclerViewContainer().setOutlineProvider(mViewOutlineProvider);
+            mAppsView.getAppsRecyclerViewContainer().setClipToOutline(true);
+            OnBackInvokedDispatcher dispatcher = findOnBackInvokedDispatcher();
+            if (dispatcher != null) {
+                dispatcher.registerOnBackInvokedCallback(
+                        OnBackInvokedDispatcher.PRIORITY_DEFAULT, this);
+            }
+        }
     }
 
     @Override
     protected void onDetachedFromWindow() {
         super.onDetachedFromWindow();
         mActivityContext.removeOnDeviceProfileChangeListener(this);
+        if (FeatureFlags.ENABLE_BACK_SWIPE_LAUNCHER_ANIMATION.get()) {
+            mAppsView.getAppsRecyclerViewContainer().setOutlineProvider(null);
+            mAppsView.getAppsRecyclerViewContainer().setClipToOutline(false);
+            OnBackInvokedDispatcher dispatcher = findOnBackInvokedDispatcher();
+            if (dispatcher != null) {
+                dispatcher.unregisterOnBackInvokedCallback(this);
+            }
+        }
     }
 
     @Override
diff --git a/src/com/android/launcher3/config/FeatureFlags.java b/src/com/android/launcher3/config/FeatureFlags.java
index cdebe440a1..18f45ebb15 100644
--- a/src/com/android/launcher3/config/FeatureFlags.java
+++ b/src/com/android/launcher3/config/FeatureFlags.java
@@ -179,7 +179,7 @@ public final class FeatureFlags {
     // TODO(Block 10): Clean up flags
     public static final BooleanFlag ENABLE_BACK_SWIPE_LAUNCHER_ANIMATION = getDebugFlag(270614790,
             "ENABLE_BACK_SWIPE_LAUNCHER_ANIMATION", DISABLED,
-            "Enables predictive back aniamtion from all apps and widgets to home");
+            "Enables predictive back animation from all apps and widgets to home");
 
     // TODO(Block 11): Clean up flags
     public static final BooleanFlag ENABLE_TWO_PANEL_HOME = getDebugFlag(270392643,