Merge "Predictive back: widget to all apps" into tm-qpr-dev am: e73db2a011 am: c5a715f531

Original change: https://googleplex-android-review.googlesource.com/c/platform/packages/apps/Launcher3/+/20968630

Change-Id: I06791cb598cb1be27a285ae98812650fe3ceffec
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>
diff --git a/quickstep/src/com/android/launcher3/taskbar/TaskbarDragLayer.java b/quickstep/src/com/android/launcher3/taskbar/TaskbarDragLayer.java
index d0059f7..7114849 100644
--- a/quickstep/src/com/android/launcher3/taskbar/TaskbarDragLayer.java
+++ b/quickstep/src/com/android/launcher3/taskbar/TaskbarDragLayer.java
@@ -194,7 +194,8 @@
     public boolean dispatchKeyEvent(KeyEvent event) {
         if (event.getAction() == ACTION_UP && event.getKeyCode() == KEYCODE_BACK) {
             AbstractFloatingView topView = AbstractFloatingView.getTopOpenView(mActivity);
-            if (topView != null && topView.onBackPressed()) {
+            if (topView != null && topView.canHandleBack()) {
+                topView.onBackInvoked();
                 // Handled by the floating view.
                 return true;
             }
diff --git a/quickstep/src/com/android/launcher3/taskbar/overlay/TaskbarOverlayDragLayer.java b/quickstep/src/com/android/launcher3/taskbar/overlay/TaskbarOverlayDragLayer.java
index 044afd6..d91b650 100644
--- a/quickstep/src/com/android/launcher3/taskbar/overlay/TaskbarOverlayDragLayer.java
+++ b/quickstep/src/com/android/launcher3/taskbar/overlay/TaskbarOverlayDragLayer.java
@@ -71,7 +71,8 @@
     public boolean dispatchKeyEvent(KeyEvent event) {
         if (event.getAction() == ACTION_UP && event.getKeyCode() == KEYCODE_BACK) {
             AbstractFloatingView topView = AbstractFloatingView.getTopOpenView(mActivity);
-            if (topView != null && topView.onBackPressed()) {
+            if (topView != null && topView.canHandleBack()) {
+                topView.onBackInvoked();
                 return true;
             }
         }
diff --git a/quickstep/src/com/android/launcher3/uioverrides/QuickstepLauncher.java b/quickstep/src/com/android/launcher3/uioverrides/QuickstepLauncher.java
index 0673dc6..30850b9 100644
--- a/quickstep/src/com/android/launcher3/uioverrides/QuickstepLauncher.java
+++ b/quickstep/src/com/android/launcher3/uioverrides/QuickstepLauncher.java
@@ -84,6 +84,7 @@
 import com.android.launcher3.Launcher;
 import com.android.launcher3.LauncherSettings.Favorites;
 import com.android.launcher3.LauncherState;
+import com.android.launcher3.OnBackPressedHandler;
 import com.android.launcher3.QuickstepAccessibilityDelegate;
 import com.android.launcher3.QuickstepTransitionManager;
 import com.android.launcher3.R;
@@ -638,20 +639,49 @@
         getOnBackInvokedDispatcher().registerOnBackInvokedCallback(
                 OnBackInvokedDispatcher.PRIORITY_DEFAULT,
                 new OnBackAnimationCallback() {
+
+                    @Nullable OnBackPressedHandler mActiveOnBackPressedHandler;
+
+                    @Override
+                    public void onBackStarted(@NonNull BackEvent backEvent) {
+                        if (mActiveOnBackPressedHandler != null) {
+                            mActiveOnBackPressedHandler.onBackCancelled();
+                        }
+                        mActiveOnBackPressedHandler = getOnBackPressedHandler();
+                        mActiveOnBackPressedHandler.onBackStarted();
+                    }
+
                     @Override
                     public void onBackInvoked() {
-                        onBackPressed();
+                        // Recreate mActiveOnBackPressedHandler if necessary to avoid NPE because:
+                        // 1. b/260636433: In 3-button-navigation mode, onBackStarted() is not
+                        // called on ACTION_DOWN before onBackInvoked() is called in ACTION_UP.
+                        // 2. Launcher#onBackPressed() will call onBackInvoked() without calling
+                        // onBackInvoked() beforehand.
+                        if (mActiveOnBackPressedHandler == null) {
+                            mActiveOnBackPressedHandler = getOnBackPressedHandler();
+                        }
+                        mActiveOnBackPressedHandler.onBackInvoked();
+                        mActiveOnBackPressedHandler = null;
                         TestLogging.recordEvent(TestProtocol.SEQUENCE_MAIN, "onBackInvoked");
                     }
 
                     @Override
                     public void onBackProgressed(@NonNull BackEvent backEvent) {
-                        QuickstepLauncher.this.onBackProgressed(backEvent.getProgress());
+                        if (!FeatureFlags.IS_STUDIO_BUILD && mActiveOnBackPressedHandler == null) {
+                            return;
+                        }
+                        mActiveOnBackPressedHandler
+                                .onBackProgressed(backEvent.getProgress());
                     }
 
                     @Override
                     public void onBackCancelled() {
-                        QuickstepLauncher.this.onBackCancelled();
+                        if (!FeatureFlags.IS_STUDIO_BUILD && mActiveOnBackPressedHandler == null) {
+                            return;
+                        }
+                        mActiveOnBackPressedHandler.onBackCancelled();
+                        mActiveOnBackPressedHandler = null;
                     }
                 });
     }
diff --git a/quickstep/src/com/android/quickstep/views/AllAppsEduView.java b/quickstep/src/com/android/quickstep/views/AllAppsEduView.java
index d79b318..716d389 100644
--- a/quickstep/src/com/android/quickstep/views/AllAppsEduView.java
+++ b/quickstep/src/com/android/quickstep/views/AllAppsEduView.java
@@ -112,11 +112,6 @@
     }
 
     @Override
-    public boolean onBackPressed() {
-        return true;
-    }
-
-    @Override
     public boolean canInterceptEventsInSystemGestureRegion() {
         return true;
     }
diff --git a/src/com/android/launcher3/AbstractFloatingView.java b/src/com/android/launcher3/AbstractFloatingView.java
index 49afc1f..796fa80 100644
--- a/src/com/android/launcher3/AbstractFloatingView.java
+++ b/src/com/android/launcher3/AbstractFloatingView.java
@@ -46,7 +46,8 @@
 /**
  * Base class for a View which shows a floating UI on top of the launcher UI.
  */
-public abstract class AbstractFloatingView extends LinearLayout implements TouchController {
+public abstract class AbstractFloatingView extends LinearLayout implements TouchController,
+        OnBackPressedHandler {
 
     @IntDef(flag = true, value = {
             TYPE_FOLDER,
@@ -165,13 +166,17 @@
 
     protected abstract boolean isOfType(@FloatingViewType int type);
 
-    /** @return Whether the back is consumed. If false, Launcher will handle the back as well. */
-    public boolean onBackPressed() {
-        close(true);
+    /** Return true if this view can consume back press. */
+    public boolean canHandleBack() {
         return true;
     }
 
     @Override
+    public void onBackInvoked() {
+        close(true);
+    }
+
+    @Override
     public boolean onControllerTouchEvent(MotionEvent ev) {
         return false;
     }
diff --git a/src/com/android/launcher3/BaseDraggingActivity.java b/src/com/android/launcher3/BaseDraggingActivity.java
index ca1fe40..6f3e948 100644
--- a/src/com/android/launcher3/BaseDraggingActivity.java
+++ b/src/com/android/launcher3/BaseDraggingActivity.java
@@ -125,9 +125,13 @@
         mCurrentActionMode = null;
     }
 
+    protected boolean isInAutoCancelActionMode() {
+        return mCurrentActionMode != null && AUTO_CANCEL_ACTION_MODE == mCurrentActionMode.getTag();
+    }
+
     @Override
     public boolean finishAutoCancelActionMode() {
-        if (mCurrentActionMode != null && AUTO_CANCEL_ACTION_MODE == mCurrentActionMode.getTag()) {
+        if (isInAutoCancelActionMode()) {
             mCurrentActionMode.finish();
             return true;
         }
diff --git a/src/com/android/launcher3/Launcher.java b/src/com/android/launcher3/Launcher.java
index de5419e..96dd569 100644
--- a/src/com/android/launcher3/Launcher.java
+++ b/src/com/android/launcher3/Launcher.java
@@ -560,6 +560,61 @@
         setTitle(R.string.home_screen);
     }
 
+    /**
+     * Provide {@link OnBackPressedHandler} in below order:
+     * <ol>
+     *  <li> auto cancel action mode handler
+     *  <li> drag handler
+     *  <li> view handler
+     *  <li> state handler
+     * </ol>
+     *
+     * A back gesture (a single click on back button, or a swipe back gesture that contains a series
+     * of swipe events) should be handled by the same handler from above list. For a new back
+     * gesture, a new handler should be regenerated.
+     *
+     * Note that state handler will always be handling the back press event if the previous 3 don't.
+     */
+    @NonNull
+    protected OnBackPressedHandler getOnBackPressedHandler() {
+        // #1 auto cancel action mode handler
+        if (isInAutoCancelActionMode()) {
+            return this::finishAutoCancelActionMode;
+        }
+
+        // #2 drag handler
+        if (mDragController.isDragging()) {
+            return mDragController::cancelDrag;
+        }
+
+        // #3 view handler
+        AbstractFloatingView topView =
+                AbstractFloatingView.getTopOpenView(Launcher.this);
+        if (topView != null && topView.canHandleBack()) {
+            return topView;
+        }
+
+        // #4 state handler
+        return new OnBackPressedHandler() {
+            @Override
+            public void onBackInvoked() {
+                onStateBack();
+            }
+
+            @Override
+            public void onBackProgressed(
+                    @FloatRange(from = 0.0, to = 1.0) float backProgress) {
+                mStateManager.getState().onBackProgressed(
+                        Launcher.this, backProgress);
+            }
+
+            @Override
+            public void onBackCancelled() {
+                mStateManager.getState().onBackCancelled(Launcher.this);
+            }
+        };
+    }
+
     protected LauncherOverlayManager getDefaultOverlay() {
         return new LauncherOverlayManager() { };
     }
@@ -2047,36 +2102,13 @@
 
     @Override
     public void onBackPressed() {
-        if (finishAutoCancelActionMode()) {
-            return;
-        }
-
-        if (mDragController.isDragging()) {
-            mDragController.cancelDrag();
-            return;
-        }
-
-        // Note: There should be at most one log per method call. This is enforced implicitly
-        // by using if-else statements.
-        AbstractFloatingView topView = AbstractFloatingView.getTopOpenView(this);
-        if (topView == null || !topView.onBackPressed()) {
-            // Not handled by the floating view.
-            onStateBack();
-        }
+        getOnBackPressedHandler().onBackInvoked();
     }
 
     protected void onStateBack() {
         mStateManager.getState().onBackPressed(this);
     }
 
-    protected void onBackProgressed(@FloatRange(from = 0.0, to = 1.0) float backProgress) {
-        mStateManager.getState().onBackProgressed(this, backProgress);
-    }
-
-    protected void onBackCancelled() {
-        mStateManager.getState().onBackCancelled(this);
-    }
-
     protected void onScreenOnChanged(boolean isOn) {
         // Reset AllApps to its initial state only if we are not in the middle of
         // processing a multi-step drop
diff --git a/src/com/android/launcher3/OnBackPressedHandler.java b/src/com/android/launcher3/OnBackPressedHandler.java
new file mode 100644
index 0000000..485aa0a
--- /dev/null
+++ b/src/com/android/launcher3/OnBackPressedHandler.java
@@ -0,0 +1,45 @@
+/*
+ * Copyright (C) 2023 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.android.launcher3;
+
+import androidx.annotation.FloatRange;
+
+/**
+ * Interface that mimics {@link android.window.OnBackInvokedCallback} without dependencies on U's
+ * API such as {@link android.window.BackEvent}.
+ *
+ * <p> Impl can assume below order during a back gesture:
+ * <ol>
+ *  <li> [optional] one {@link #onBackStarted()} will be called to start the gesture
+ *  <li> zero or multiple {@link #onBackProgressed(float)} will be called during swipe gesture
+ *  <li> either one of {@link #onBackInvoked()} or {@link #onBackCancelled()} will be called to end
+ *  the gesture
+ */
+public interface OnBackPressedHandler {
+
+    /** Called when back has started. */
+    default void onBackStarted() {}
+
+    /** Called when back is committed. */
+    void onBackInvoked();
+
+    /** Called with back gesture's progress. */
+    default void onBackProgressed(@FloatRange(from = 0.0, to = 1.0) float backProgress) {}
+
+    /** Called when user drops the back gesture. */
+    default void onBackCancelled() {}
+}
diff --git a/src/com/android/launcher3/allapps/DiscoveryBounce.java b/src/com/android/launcher3/allapps/DiscoveryBounce.java
index be261f7..0188a47 100644
--- a/src/com/android/launcher3/allapps/DiscoveryBounce.java
+++ b/src/com/android/launcher3/allapps/DiscoveryBounce.java
@@ -81,10 +81,10 @@
     }
 
     @Override
-    public boolean onBackPressed() {
-        super.onBackPressed();
-        // Go back to the previous state (from a user's perspective this floating view isn't
-        // something to go back from).
+    public boolean canHandleBack() {
+        // Since DiscoveryBounce doesn't handle back, onBackInvoked() won't be called and we should
+        // close it without animation.
+        close(false);
         return false;
     }
 
diff --git a/src/com/android/launcher3/folder/Folder.java b/src/com/android/launcher3/folder/Folder.java
index 94eea35..9a5d77e 100644
--- a/src/com/android/launcher3/folder/Folder.java
+++ b/src/com/android/launcher3/folder/Folder.java
@@ -1579,17 +1579,14 @@
         return getOpenView(activityContext, TYPE_FOLDER);
     }
 
-    /**
-     * Navigation bar back key or hardware input back key has been issued.
-     */
+    /** Navigation bar back key or hardware input back key has been issued. */
     @Override
-    public boolean onBackPressed() {
+    public void onBackInvoked() {
         if (isEditingName()) {
             mFolderName.dispatchBackKey();
         } else {
-            super.onBackPressed();
+            super.onBackInvoked();
         }
-        return true;
     }
 
     @Override
diff --git a/src/com/android/launcher3/secondarydisplay/SecondaryDisplayLauncher.java b/src/com/android/launcher3/secondarydisplay/SecondaryDisplayLauncher.java
index a2353d8..56dffa9 100644
--- a/src/com/android/launcher3/secondarydisplay/SecondaryDisplayLauncher.java
+++ b/src/com/android/launcher3/secondarydisplay/SecondaryDisplayLauncher.java
@@ -175,8 +175,9 @@
         // Note: There should be at most one log per method call. This is enforced implicitly
         // by using if-else statements.
         AbstractFloatingView topView = AbstractFloatingView.getTopOpenView(this);
-        if (topView != null && topView.onBackPressed()) {
+        if (topView != null && topView.canHandleBack()) {
             // Handled by the floating view.
+            topView.onBackInvoked();
         } else {
             showAppDrawer(false);
         }
diff --git a/src/com/android/launcher3/widget/picker/WidgetsFullSheet.java b/src/com/android/launcher3/widget/picker/WidgetsFullSheet.java
index 38cdb4b..c78ecf5 100644
--- a/src/com/android/launcher3/widget/picker/WidgetsFullSheet.java
+++ b/src/com/android/launcher3/widget/picker/WidgetsFullSheet.java
@@ -17,7 +17,9 @@
 
 import static android.view.View.MeasureSpec.makeMeasureSpec;
 
+import static com.android.launcher3.LauncherAnimUtils.SCALE_PROPERTY;
 import static com.android.launcher3.LauncherAnimUtils.VIEW_TRANSLATE_Y;
+import static com.android.launcher3.allapps.AllAppsTransitionController.SWIPE_ALL_APPS_TO_HOME_MIN_SCALE;
 import static com.android.launcher3.logging.StatsLogManager.LauncherEvent.LAUNCHER_WIDGETSTRAY_SEARCHED;
 import static com.android.launcher3.testing.shared.TestProtocol.NORMAL_STATE_ORDINAL;
 
@@ -45,6 +47,7 @@
 import android.widget.Button;
 import android.widget.TextView;
 
+import androidx.annotation.FloatRange;
 import androidx.annotation.Nullable;
 import androidx.annotation.VisibleForTesting;
 import androidx.recyclerview.widget.DefaultItemAnimator;
@@ -54,6 +57,7 @@
 import com.android.launcher3.LauncherAppState;
 import com.android.launcher3.R;
 import com.android.launcher3.Utilities;
+import com.android.launcher3.anim.Interpolators;
 import com.android.launcher3.anim.PendingAnimation;
 import com.android.launcher3.compat.AccessibilityManagerCompat;
 import com.android.launcher3.model.UserManagerState;
@@ -264,6 +268,15 @@
         attachScrollbarToRecyclerView(currentRecyclerView);
     }
 
+    @Override
+    public void onBackProgressed(@FloatRange(from = 0.0, to = 1.0) float progress) {
+        float deceleratedProgress =
+                Interpolators.PREDICTIVE_BACK_DECELERATED_EASE.getInterpolation(progress);
+        float scaleProgress = SWIPE_ALL_APPS_TO_HOME_MIN_SCALE
+                + (1 - SWIPE_ALL_APPS_TO_HOME_MIN_SCALE) * (1 - deceleratedProgress);
+        SCALE_PROPERTY.set(this, scaleProgress);
+    }
+
     private void attachScrollbarToRecyclerView(WidgetsRecyclerView recyclerView) {
         recyclerView.bindFastScrollbar();
         if (mCurrentWidgetsRecyclerView != recyclerView) {
@@ -736,12 +749,12 @@
     }
 
     @Override
-    public boolean onBackPressed() {
+    public void onBackInvoked() {
         if (mIsInSearchMode) {
             mSearchBar.reset();
-            return true;
+        } else {
+            super.onBackInvoked();
         }
-        return super.onBackPressed();
     }
 
     @Override