Removing extraneous calls.

- Removing calls to ensureCapacity, which was causing reallocations when
  using a temporary set with multiple uses.
- Fixing issue with update callback not being called when immediately 
  updating a TaskView’s transform
- Adding utility methods in preparation for refactoring code


Change-Id: If62c3751ed6af15092a34435df08bb4d627536ea
diff --git a/packages/SystemUI/src/com/android/systemui/SwipeHelper.java b/packages/SystemUI/src/com/android/systemui/SwipeHelper.java
index fabc7b7..d28da41 100644
--- a/packages/SystemUI/src/com/android/systemui/SwipeHelper.java
+++ b/packages/SystemUI/src/com/android/systemui/SwipeHelper.java
@@ -135,7 +135,7 @@
 
     private ObjectAnimator createTranslationAnimation(View v, float newPos) {
         ObjectAnimator anim = ObjectAnimator.ofFloat(v,
-                mSwipeDirection == X ? "translationX" : "translationY", newPos);
+                mSwipeDirection == X ? View.TRANSLATION_X : View.TRANSLATION_Y, newPos);
         return anim;
     }
 
@@ -401,9 +401,17 @@
                 mCallback.onChildSnappedBack(animView);
             }
         });
+        updateSnapBackAnimation(anim);
         anim.start();
     }
 
+    /**
+     * Called to update the snap back animation.
+     */
+    protected void updateSnapBackAnimation(Animator anim) {
+        // Do nothing
+    }
+
     public boolean onTouchEvent(MotionEvent ev) {
         if (mLongPressSent) {
             return true;
diff --git a/packages/SystemUI/src/com/android/systemui/recents/misc/Utilities.java b/packages/SystemUI/src/com/android/systemui/recents/misc/Utilities.java
index 33f116b..f3c4cc3 100644
--- a/packages/SystemUI/src/com/android/systemui/recents/misc/Utilities.java
+++ b/packages/SystemUI/src/com/android/systemui/recents/misc/Utilities.java
@@ -21,10 +21,16 @@
 import android.graphics.Rect;
 import android.graphics.RectF;
 import android.graphics.drawable.Drawable;
+import android.util.ArraySet;
 import android.util.IntProperty;
 import android.util.Property;
 import android.view.View;
 import android.view.ViewParent;
+import com.android.systemui.recents.model.Task;
+import com.android.systemui.recents.views.TaskViewTransform;
+
+import java.util.Collections;
+import java.util.List;
 
 /* Common code */
 public class Utilities {
@@ -71,6 +77,28 @@
         return null;
     }
 
+    /**
+     * Initializes the {@param setOut} with the given object.
+     */
+    public static <T> ArraySet<T> objectToSet(T obj, ArraySet<T> setOut) {
+        setOut.clear();
+        if (obj != null) {
+            setOut.add(obj);
+        }
+        return setOut;
+    }
+
+    /**
+     * Replaces the contents of {@param setOut} with the contents of the {@param array}.
+     */
+    public static <T> ArraySet<T> arrayToSet(T[] array, ArraySet<T> setOut) {
+        setOut.clear();
+        if (array != null) {
+            Collections.addAll(setOut, array);
+        }
+        return setOut;
+    }
+
     /** Scales a rect about its centroid */
     public static void scaleRectAboutCenter(RectF r, float scale) {
         if (scale != 1.0f) {
@@ -127,4 +155,22 @@
             animator.cancel();
         }
     }
+
+    /**
+     * Updates {@param transforms} to be the same size as {@param tasks}.
+     */
+    public static void matchTaskListSize(List<Task> tasks, List<TaskViewTransform> transforms) {
+        // We can reuse the task transforms where possible to reduce object allocation
+        int taskTransformCount = transforms.size();
+        int taskCount = tasks.size();
+        if (taskTransformCount < taskCount) {
+            // If there are less transforms than tasks, then add as many transforms as necessary
+            for (int i = taskTransformCount; i < taskCount; i++) {
+                transforms.add(new TaskViewTransform());
+            }
+        } else if (taskTransformCount > taskCount) {
+            // If there are more transforms than tasks, then just subset the transform list
+            transforms.subList(taskCount, taskTransformCount).clear();
+        }
+    }
 }
diff --git a/packages/SystemUI/src/com/android/systemui/recents/model/TaskGrouping.java b/packages/SystemUI/src/com/android/systemui/recents/model/TaskGrouping.java
index 15f6b0a..2109376 100644
--- a/packages/SystemUI/src/com/android/systemui/recents/model/TaskGrouping.java
+++ b/packages/SystemUI/src/com/android/systemui/recents/model/TaskGrouping.java
@@ -98,7 +98,6 @@
         int taskCount = mTaskKeys.size();
         mFrontMostTaskKey = mTaskKeys.get(mTaskKeys.size() - 1);
         mTaskKeyIndices.clear();
-        mTaskKeyIndices.ensureCapacity(taskCount);
         for (int i = 0; i < taskCount; i++) {
             Task.TaskKey k = mTaskKeys.get(i);
             mTaskKeyIndices.put(k, i);
diff --git a/packages/SystemUI/src/com/android/systemui/recents/model/TaskStack.java b/packages/SystemUI/src/com/android/systemui/recents/model/TaskStack.java
index 21d0bb6..327cdf8 100644
--- a/packages/SystemUI/src/com/android/systemui/recents/model/TaskStack.java
+++ b/packages/SystemUI/src/com/android/systemui/recents/model/TaskStack.java
@@ -193,7 +193,6 @@
     private void updateFilteredTaskIndices() {
         int taskCount = mFilteredTasks.size();
         mTaskIndices.clear();
-        mTaskIndices.ensureCapacity(taskCount);
         for (int i = 0; i < taskCount; i++) {
             Task t = mFilteredTasks.get(i);
             mTaskIndices.put(t.key, i);
@@ -841,7 +840,6 @@
             ArrayMap<Task.TaskKey, Task> tasksMap = new ArrayMap<>();
             ArrayList<Task> tasks = mStackTaskList.getTasks();
             int taskCount = tasks.size();
-            tasksMap.ensureCapacity(taskCount);
             for (int i = 0; i < taskCount; i++) {
                 Task t = tasks.get(i);
                 TaskGrouping group;
diff --git a/packages/SystemUI/src/com/android/systemui/recents/views/AnimateableViewBounds.java b/packages/SystemUI/src/com/android/systemui/recents/views/AnimateableViewBounds.java
index b8bbf51..5a72897 100644
--- a/packages/SystemUI/src/com/android/systemui/recents/views/AnimateableViewBounds.java
+++ b/packages/SystemUI/src/com/android/systemui/recents/views/AnimateableViewBounds.java
@@ -58,6 +58,7 @@
     void setAlpha(float alpha) {
         if (Float.compare(alpha, mAlpha) != 0) {
             mAlpha = alpha;
+            // TODO, If both clip and alpha change in the same frame, only invalidate once
             mSourceView.invalidateOutline();
         }
     }
@@ -79,6 +80,7 @@
                 mSourceView.getHeight() - Math.max(0, mClipRect.bottom));
         if (!mLastClipBounds.equals(mClipBounds)) {
             mSourceView.setClipBounds(mClipBounds);
+            // TODO, If both clip and alpha change in the same frame, only invalidate once
             mSourceView.invalidateOutline();
             mLastClipBounds.set(mClipBounds);
         }
diff --git a/packages/SystemUI/src/com/android/systemui/recents/views/FreeformWorkspaceLayoutAlgorithm.java b/packages/SystemUI/src/com/android/systemui/recents/views/FreeformWorkspaceLayoutAlgorithm.java
index d3a1e91..491c4c2 100644
--- a/packages/SystemUI/src/com/android/systemui/recents/views/FreeformWorkspaceLayoutAlgorithm.java
+++ b/packages/SystemUI/src/com/android/systemui/recents/views/FreeformWorkspaceLayoutAlgorithm.java
@@ -48,7 +48,6 @@
     public void update(List<Task> freeformTasks, TaskStackLayoutAlgorithm stackLayout) {
         Collections.reverse(freeformTasks);
         mTaskRectMap.clear();
-        mTaskRectMap.ensureCapacity(freeformTasks.size());
 
         int numFreeformTasks = stackLayout.mNumFreeformTasks;
         if (!freeformTasks.isEmpty()) {
diff --git a/packages/SystemUI/src/com/android/systemui/recents/views/RecentsView.java b/packages/SystemUI/src/com/android/systemui/recents/views/RecentsView.java
index 1a2f64e..e727652 100644
--- a/packages/SystemUI/src/com/android/systemui/recents/views/RecentsView.java
+++ b/packages/SystemUI/src/com/android/systemui/recents/views/RecentsView.java
@@ -59,6 +59,7 @@
 import com.android.systemui.recents.events.ui.dragndrop.DragStartEvent;
 import com.android.systemui.recents.misc.ReferenceCountedTrigger;
 import com.android.systemui.recents.misc.SystemServicesProxy;
+import com.android.systemui.recents.misc.Utilities;
 import com.android.systemui.recents.model.Task;
 import com.android.systemui.recents.model.TaskStack;
 import com.android.systemui.stackdivider.WindowManagerProxy;
@@ -66,7 +67,6 @@
 import com.android.systemui.statusbar.phone.PhoneStatusBar;
 
 import java.util.ArrayList;
-import java.util.Collections;
 import java.util.List;
 
 import static android.app.ActivityManager.StackId.INVALID_STACK_ID;
@@ -665,10 +665,8 @@
     private void updateVisibleDockRegions(TaskStack.DockState[] newDockStates,
             boolean isDefaultDockState, int overrideAlpha, boolean animateAlpha,
             boolean animateBounds) {
-        ArraySet<TaskStack.DockState> newDockStatesSet = new ArraySet<>();
-        if (newDockStates != null) {
-            Collections.addAll(newDockStatesSet, newDockStates);
-        }
+        ArraySet<TaskStack.DockState> newDockStatesSet = Utilities.arrayToSet(newDockStates,
+                new ArraySet<TaskStack.DockState>());
         ArrayList<TaskStack.DockState> visDockStates = mTouchHandler.getVisibleDockStates();
         for (int i = visDockStates.size() - 1; i >= 0; i--) {
             TaskStack.DockState dockState = visDockStates.get(i);
diff --git a/packages/SystemUI/src/com/android/systemui/recents/views/TaskStackLayoutAlgorithm.java b/packages/SystemUI/src/com/android/systemui/recents/views/TaskStackLayoutAlgorithm.java
index 2fa99ce..68ff63c 100644
--- a/packages/SystemUI/src/com/android/systemui/recents/views/TaskStackLayoutAlgorithm.java
+++ b/packages/SystemUI/src/com/android/systemui/recents/views/TaskStackLayoutAlgorithm.java
@@ -408,7 +408,6 @@
         // Put each of the tasks in the progress map at a fixed index (does not need to actually
         // map to a scroll position, just by index)
         int taskCount = stackTasks.size();
-        mTaskIndexMap.ensureCapacity(taskCount);
         for (int i = 0; i < taskCount; i++) {
             Task task = stackTasks.get(i);
             mTaskIndexMap.put(task.key, i);
diff --git a/packages/SystemUI/src/com/android/systemui/recents/views/TaskStackView.java b/packages/SystemUI/src/com/android/systemui/recents/views/TaskStackView.java
index 713cfc3..7583a19 100644
--- a/packages/SystemUI/src/com/android/systemui/recents/views/TaskStackView.java
+++ b/packages/SystemUI/src/com/android/systemui/recents/views/TaskStackView.java
@@ -357,15 +357,7 @@
         int backMostVisibleIndex = -1;
 
         // We can reuse the task transforms where possible to reduce object allocation
-        if (taskTransformCount < taskCount) {
-            // If there are less transforms than tasks, then add as many transforms as necessary
-            for (int i = taskTransformCount; i < taskCount; i++) {
-                taskTransforms.add(new TaskViewTransform());
-            }
-        } else if (taskTransformCount > taskCount) {
-            // If there are more transforms than tasks, then just subset the transform list
-            taskTransforms.subList(0, taskCount);
-        }
+        Utilities.matchTaskListSize(tasks, taskTransforms);
 
         // Update the stack transforms
         TaskViewTransform frontTransform = null;
diff --git a/packages/SystemUI/src/com/android/systemui/recents/views/TaskStackViewTouchHandler.java b/packages/SystemUI/src/com/android/systemui/recents/views/TaskStackViewTouchHandler.java
index a0bb0ef..4813c19 100644
--- a/packages/SystemUI/src/com/android/systemui/recents/views/TaskStackViewTouchHandler.java
+++ b/packages/SystemUI/src/com/android/systemui/recents/views/TaskStackViewTouchHandler.java
@@ -16,11 +16,11 @@
 
 package com.android.systemui.recents.views;
 
+import android.animation.Animator;
 import android.animation.ValueAnimator;
 import android.content.Context;
 import android.content.res.Resources;
 import android.graphics.Rect;
-import android.util.DisplayMetrics;
 import android.util.Log;
 import android.view.InputDevice;
 import android.view.MotionEvent;
@@ -95,6 +95,11 @@
             protected float getSize(View v) {
                 return mSv.getWidth();
             }
+
+            @Override
+            protected void updateSnapBackAnimation(Animator anim) {
+                anim.setInterpolator(mSv.mFastOutSlowInInterpolator);
+            }
         };
         mSwipeHelper.setDisableHardwareLayers(true);
     }
diff --git a/packages/SystemUI/src/com/android/systemui/recents/views/TaskView.java b/packages/SystemUI/src/com/android/systemui/recents/views/TaskView.java
index db4db63..9b72702 100644
--- a/packages/SystemUI/src/com/android/systemui/recents/views/TaskView.java
+++ b/packages/SystemUI/src/com/android/systemui/recents/views/TaskView.java
@@ -260,17 +260,23 @@
             if (Float.compare(getTaskProgress(), toTransform.p) != 0) {
                 setTaskProgress(toTransform.p);
             }
+            // Manually call back to the animator listener and update callback
             if (toAnimation.listener != null) {
                 toAnimation.listener.onAnimationEnd(null);
             }
+            if (updateCallback != null) {
+                updateCallback.onAnimationUpdate(null);
+            }
         } else {
             if (Float.compare(getTaskProgress(), toTransform.p) != 0) {
                 mTmpAnimators.add(ObjectAnimator.ofFloat(this, TASK_PROGRESS, getTaskProgress(),
                         toTransform.p));
             }
-            ValueAnimator updateCallbackAnim = ValueAnimator.ofInt(0, 1);
-            updateCallbackAnim.addUpdateListener(updateCallback);
-            mTmpAnimators.add(updateCallbackAnim);
+            if (updateCallback != null) {
+                ValueAnimator updateCallbackAnim = ValueAnimator.ofInt(0, 1);
+                updateCallbackAnim.addUpdateListener(updateCallback);
+                mTmpAnimators.add(updateCallbackAnim);
+            }
 
             // Create the animator
             mTransformAnimation = toAnimation.createAnimator(mTmpAnimators);