Adding animation when destroying folder due to single item remaining

Change-Id: I079af9a50d7d6f63092b725ecd941ab1e298032d
diff --git a/src/com/android/launcher2/FolderIcon.java b/src/com/android/launcher2/FolderIcon.java
index 4919b57..76f3114 100644
--- a/src/com/android/launcher2/FolderIcon.java
+++ b/src/com/android/launcher2/FolderIcon.java
@@ -50,8 +50,8 @@
  */
 public class FolderIcon extends LinearLayout implements FolderListener {
     private Launcher mLauncher;
-    Folder mFolder;
-    FolderInfo mInfo;
+    private Folder mFolder;
+    private FolderInfo mInfo;
     private static boolean sStaticValuesDirty = true;
 
     private CheckLongPressHelper mLongPressHelper;
@@ -61,6 +61,7 @@
     private static final int CONSUMPTION_ANIMATION_DURATION = 100;
     private static final int DROP_IN_ANIMATION_DURATION = 400;
     private static final int INITIAL_ITEM_ANIMATION_DURATION = 350;
+    private static final int FINAL_ITEM_ANIMATION_DURATION = 200;
 
     // The degree to which the inner ring grows when accepting drop
     private static final float INNER_RING_GROWTH_FACTOR = 0.15f;
@@ -93,8 +94,10 @@
     private int mPreviewOffsetY;
     private float mMaxPerspectiveShift;
     boolean mAnimating = false;
+
     private PreviewItemDrawingParams mParams = new PreviewItemDrawingParams(0, 0, 0, 0);
     private PreviewItemDrawingParams mAnimParams = new PreviewItemDrawingParams(0, 0, 0, 0);
+    private ArrayList<ShortcutInfo> mHiddenItems = new ArrayList<ShortcutInfo>();
 
     public FolderIcon(Context context, AttributeSet attrs) {
         super(context, attrs);
@@ -278,6 +281,14 @@
         }
     }
 
+    Folder getFolder() {
+        return mFolder;
+    }
+
+    FolderInfo getFolderInfo() {
+        return mInfo;
+    }
+
     private boolean willAcceptItem(ItemInfo item) {
         final int itemType = item.itemType;
         return ((itemType == LauncherSettings.Favorites.ITEM_TYPE_APPLICATION ||
@@ -287,7 +298,7 @@
 
     public boolean acceptDrop(Object dragInfo) {
         final ItemInfo item = (ItemInfo) dragInfo;
-        return willAcceptItem(item);
+        return !mFolder.isDestroyed() && willAcceptItem(item);
     }
 
     public void addItem(ShortcutInfo item) {
@@ -296,7 +307,7 @@
     }
 
     public void onDragEnter(Object dragInfo) {
-        if (!willAcceptItem((ItemInfo) dragInfo)) return;
+        if (mFolder.isDestroyed() || !willAcceptItem((ItemInfo) dragInfo)) return;
         CellLayout.LayoutParams lp = (CellLayout.LayoutParams) getLayoutParams();
         CellLayout layout = (CellLayout) getParent().getParent();
         mFolderRingAnimator.setCell(lp.cellX, lp.cellY);
@@ -312,16 +323,29 @@
             final ShortcutInfo srcInfo, final DragView srcView, Rect dstRect,
             float scaleRelativeToDragLayer, Runnable postAnimationRunnable) {
 
+        // These correspond two the drawable and view that the icon was dropped _onto_
         Drawable animateDrawable = ((TextView) destView).getCompoundDrawables()[1];
-        computePreviewDrawingParams(animateDrawable.getIntrinsicWidth(), destView.getMeasuredWidth());
-
-        // This will animate the dragView (srcView) into the new folder
-        onDrop(srcInfo, srcView, dstRect, scaleRelativeToDragLayer, 1, postAnimationRunnable, null);
+        computePreviewDrawingParams(animateDrawable.getIntrinsicWidth(),
+                destView.getMeasuredWidth());
 
         // This will animate the first item from it's position as an icon into its
         // position as the first item in the preview
-        animateFirstItem(animateDrawable, INITIAL_ITEM_ANIMATION_DURATION);
+        animateFirstItem(animateDrawable, INITIAL_ITEM_ANIMATION_DURATION, false, null);
         addItem(destInfo);
+
+        // This will animate the dragView (srcView) into the new folder
+        onDrop(srcInfo, srcView, dstRect, scaleRelativeToDragLayer, 1, postAnimationRunnable, null);
+    }
+
+    public void performDestroyAnimation(final View finalView, Runnable onCompleteRunnable) {
+        Drawable animateDrawable = ((TextView) finalView).getCompoundDrawables()[1];
+        computePreviewDrawingParams(animateDrawable.getIntrinsicWidth(), 
+                finalView.getMeasuredWidth());
+
+        // This will animate the first item from it's position as an icon into its
+        // position as the first item in the preview
+        animateFirstItem(animateDrawable, FINAL_ITEM_ANIMATION_DURATION, true,
+                onCompleteRunnable);
     }
 
     public void onDragExit(Object dragInfo) {
@@ -377,9 +401,12 @@
                     1, 1, finalScale, finalScale, DROP_IN_ANIMATION_DURATION,
                     new DecelerateInterpolator(2), new AccelerateInterpolator(2),
                     postAnimationRunnable, DragLayer.ANIMATION_END_DISAPPEAR, null);
+            addItem(item);
+            mHiddenItems.add(item);
             postDelayed(new Runnable() {
                 public void run() {
-                    addItem(item);
+                    mHiddenItems.remove(item);
+                    invalidate();
                 }
             }, DROP_IN_ANIMATION_DURATION);
         } else {
@@ -526,19 +553,20 @@
         if (!mAnimating) {
             for (int i = nItemsInPreview - 1; i >= 0; i--) {
                 v = (TextView) items.get(i);
-                d = v.getCompoundDrawables()[1];
-
-                mParams = computePreviewItemDrawingParams(i, mParams);
-                mParams.drawable = d;
-                drawPreviewItem(canvas, mParams);
+                if (!mHiddenItems.contains(v.getTag())) {
+                    d = v.getCompoundDrawables()[1];
+                    mParams = computePreviewItemDrawingParams(i, mParams);
+                    mParams.drawable = d;
+                    drawPreviewItem(canvas, mParams);
+                }
             }
         } else {
             drawPreviewItem(canvas, mAnimParams);
         }
     }
 
-    private void animateFirstItem(final Drawable d, int duration) {
-        computePreviewDrawingParams(d);
+    private void animateFirstItem(final Drawable d, int duration, final boolean reverse,
+            final Runnable onCompleteRunnable) {
         final PreviewItemDrawingParams finalParams = computePreviewItemDrawingParams(0, null);
 
         final float scale0 = 1.0f;
@@ -550,6 +578,10 @@
         va.addUpdateListener(new AnimatorUpdateListener(){
             public void onAnimationUpdate(ValueAnimator animation) {
                 float progress = (Float) animation.getAnimatedValue();
+                if (reverse) {
+                    progress = 1 - progress;
+                    mPreviewBackground.setAlpha(progress);
+                }
 
                 mAnimParams.transX = transX0 + progress * (finalParams.transX - transX0);
                 mAnimParams.transY = transY0 + progress * (finalParams.transY - transY0);
@@ -565,6 +597,9 @@
             @Override
             public void onAnimationEnd(Animator animation) {
                 mAnimating = false;
+                if (onCompleteRunnable != null) {
+                    onCompleteRunnable.run();
+                }
             }
         });
         va.setDuration(duration);