2D Recents: fix toggling behavior

am: a96a617a4e

Change-Id: I8978e8ae81e3566e83ca3d7819b95d54c5861b67

packages/SystemUI/src/com/android/systemui/recents/RecentsImpl.java

@@ -50,6 +50,7 @@ import com.android.systemui.recents.events.activity.DockedTopTaskEvent;
 import com.android.systemui.recents.events.activity.EnterRecentsWindowLastAnimationFrameEvent;
 import com.android.systemui.recents.events.activity.HideRecentsEvent;
 import com.android.systemui.recents.events.activity.IterateRecentsEvent;
+import com.android.systemui.recents.events.activity.LaunchMostRecentTaskRequestEvent;
 import com.android.systemui.recents.events.activity.LaunchNextTaskRequestEvent;
 import com.android.systemui.recents.events.activity.RecentsActivityStartingEvent;
 import com.android.systemui.recents.events.activity.ToggleRecentsEvent;
@@ -303,16 +304,24 @@ public class RecentsImpl implements ActivityOptions.OnAnimationFinishedListener
                 RecentsConfiguration config = Recents.getConfiguration();
                 RecentsActivityLaunchState launchState = config.getLaunchState();
                 if (!launchState.launchedWithAltTab) {
-                    // If the user taps quickly
+                    // Has the user tapped quickly?
-                    if (!debugFlags.isPagingEnabled() ||
+                    boolean isQuickTap = ViewConfiguration.getDoubleTapMinTime() < elapsedTime &&
-                            (ViewConfiguration.getDoubleTapMinTime() < elapsedTime &&
+                            elapsedTime < ViewConfiguration.getDoubleTapTimeout();
-                                    elapsedTime < ViewConfiguration.getDoubleTapTimeout())) {
+                    if (Recents.getConfiguration().isGridEnabled) {
+                        if (isQuickTap) {
+                            EventBus.getDefault().post(new LaunchNextTaskRequestEvent());
+                        } else {
+                            EventBus.getDefault().post(new LaunchMostRecentTaskRequestEvent());
+                        }
+                    } else {
+                        if (!debugFlags.isPagingEnabled() || isQuickTap) {
                             // Launch the next focused task
                             EventBus.getDefault().post(new LaunchNextTaskRequestEvent());
                         } else {
                             // Notify recents to move onto the next task
                             EventBus.getDefault().post(new IterateRecentsEvent());
                         }
+                    }
                 } else {
                     // If the user has toggled it too quickly, then just eat up the event here (it's
                     // better than showing a janky screenshot).

packages/SystemUI/src/com/android/systemui/recents/events/activity/LaunchMostRecentTaskRequestEvent.java

@@ -0,0 +1,26 @@
+/*
+ * Copyright (C) 2017 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.systemui.recents.events.activity;
+
+import com.android.systemui.recents.events.EventBus;
+
+/**
+ * This event is sent to request that the most recent task is launched.
+ */
+public class LaunchMostRecentTaskRequestEvent extends EventBus.Event {
+    // Simple event
+}

packages/SystemUI/src/com/android/systemui/recents/views/TaskStackView.java

@@ -64,6 +64,7 @@ import com.android.systemui.recents.events.activity.EnterRecentsWindowAnimationC
 import com.android.systemui.recents.events.activity.HideRecentsEvent;
 import com.android.systemui.recents.events.activity.HideStackActionButtonEvent;
 import com.android.systemui.recents.events.activity.IterateRecentsEvent;
+import com.android.systemui.recents.events.activity.LaunchMostRecentTaskRequestEvent;
 import com.android.systemui.recents.events.activity.LaunchNextTaskRequestEvent;
 import com.android.systemui.recents.events.activity.LaunchTaskEvent;
 import com.android.systemui.recents.events.activity.LaunchTaskStartedEvent;
@@ -1733,6 +1734,13 @@ public class TaskStackView extends FrameLayout implements TaskStack.TaskStackCal
         mUIDozeTrigger.stopDozing();
     }
 
+    public final void onBusEvent(LaunchMostRecentTaskRequestEvent event) {
+        if (mStack.getTaskCount() > 0) {
+            Task mostRecentTask = mStack.getStackFrontMostTask(true /* includeFreefromTasks */);
+            launchTask(mostRecentTask);
+        }
+    }
+
     public final void onBusEvent(LaunchNextTaskRequestEvent event) {
         if (mAwaitingFirstLayout) {
             mLaunchNextAfterFirstMeasure = true;
@@ -1741,29 +1749,7 @@ public class TaskStackView extends FrameLayout implements TaskStack.TaskStackCal
 
         final Task launchTask = mStack.getNextLaunchTarget();
         if (launchTask != null) {
-            // Stop all animations
+            launchTask(launchTask);
-            cancelAllTaskViewAnimations();
-
-            float curScroll = mStackScroller.getStackScroll();
-            float targetScroll = mLayoutAlgorithm.getStackScrollForTaskAtInitialOffset(launchTask);
-            float absScrollDiff = Math.abs(targetScroll - curScroll);
-            if (getChildViewForTask(launchTask) == null || absScrollDiff > 0.35f) {
-                int duration = (int) (LAUNCH_NEXT_SCROLL_BASE_DURATION +
-                        absScrollDiff * LAUNCH_NEXT_SCROLL_INCR_DURATION);
-                mStackScroller.animateScroll(targetScroll,
-                        duration, new Runnable() {
-                            @Override
-                            public void run() {
-                                EventBus.getDefault().send(new LaunchTaskEvent(
-                                        getChildViewForTask(launchTask), launchTask, null,
-                                        INVALID_STACK_ID, false /* screenPinningRequested */));
-                            }
-                        });
-            } else {
-                EventBus.getDefault().send(new LaunchTaskEvent(getChildViewForTask(launchTask),
-                        launchTask, null, INVALID_STACK_ID, false /* screenPinningRequested */));
-            }
-
             MetricsLogger.action(getContext(), MetricsEvent.OVERVIEW_LAUNCH_PREVIOUS_TASK,
                     launchTask.key.getComponent().toString());
         } else if (mStack.getTaskCount() == 0) {
@@ -2215,6 +2201,31 @@ public class TaskStackView extends FrameLayout implements TaskStack.TaskStackCal
         return -1;
     }
 
+    private void launchTask(Task task) {
+        // Stop all animations
+        cancelAllTaskViewAnimations();
+
+        float curScroll = mStackScroller.getStackScroll();
+        float targetScroll = mLayoutAlgorithm.getStackScrollForTaskAtInitialOffset(task);
+        float absScrollDiff = Math.abs(targetScroll - curScroll);
+        if (getChildViewForTask(task) == null || absScrollDiff > 0.35f) {
+            int duration = (int) (LAUNCH_NEXT_SCROLL_BASE_DURATION +
+                    absScrollDiff * LAUNCH_NEXT_SCROLL_INCR_DURATION);
+            mStackScroller.animateScroll(targetScroll,
+                    duration, new Runnable() {
+                        @Override
+                        public void run() {
+                            EventBus.getDefault().send(new LaunchTaskEvent(
+                                    getChildViewForTask(task), task, null,
+                                    INVALID_STACK_ID, false /* screenPinningRequested */));
+                        }
+                    });
+        } else {
+            EventBus.getDefault().send(new LaunchTaskEvent(getChildViewForTask(task),
+                    task, null, INVALID_STACK_ID, false /* screenPinningRequested */));
+        }
+    }
+
     /**
      * Check whether we should use the grid layout.
      */