Add per-item animations to the menu

chrome/android/java/src/org/chromium/chrome/browser/appmenu/AppMenu.java

 // Copyright 2011 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 package org.chromium.chrome.browser.appmenu;
 
+import android.animation.Animator;
+import android.animation.AnimatorSet;
 import android.content.Context;
 import android.content.res.Resources;
 import android.graphics.Rect;
 import android.view.KeyEvent;
 import android.view.LayoutInflater;
 import android.view.Menu;
 import android.view.MenuItem;
 import android.view.Surface;
 import android.view.View;
 import android.view.View.OnKeyListener;
@@ skipping 123 matching lines @@
         mPopup.show();
         mPopup.getListView().setItemsCanFocus(true);
         mPopup.getListView().setOnKeyListener(this);
 
         mHandler.onMenuVisibilityChanged(true);
 
         if (mVerticalFadeDistance > 0) {
             mPopup.getListView().setVerticalFadingEdgeEnabled(true);
             mPopup.getListView().setFadingEdgeLength(mVerticalFadeDistance);
         }
+
+        mPopup.getListView().addOnLayoutChangeListener(new View.OnLayoutChangeListener() {
+            @Override
+            public void onLayoutChange(View v, int left, int top, int right, int bottom,
+                    int oldLeft, int oldTop, int oldRight, int oldBottom) {
+                mPopup.getListView().removeOnLayoutChangeListener(this);
+                runMenuItemEnterAnimations();
+            }
+        });
     }
 
     private void setPopupOffset(ListPopupWindow popup, int screenRotation, Rect appRect) {
         Rect paddingRect = new Rect();
         popup.getBackground().getPadding(paddingRect);
         int[] anchorLocation = new int[2];
         popup.getAnchorView().getLocationInWindow(anchorLocation);
 
         // If we have a hardware menu button, locate the app menu closer to the estimated
         // hardware menu button location.
@@ skipping 58 matching lines @@
             }
         }
         return false;
     }
 
     /**
      * Dismisses the app menu and cancels the drag-to-scroll if it is taking place.
      */
     void dismiss() {
         mHandler.appMenuDismissed();
-        if (isShowing()) mPopup.dismiss();
+        if (isShowing()) {
+            mPopup.dismiss();
+        }
     }
 
     /**
      * @return Whether the app menu is currently showing.
      */
     boolean isShowing() {
         if (mPopup == null) {
             return false;
         }
         return mPopup.isShowing();
@@ skipping 31 matching lines @@
                 mPopup.setHeight(spaceForFullItems + spaceForPartialItem +
                         padding.top + padding.bottom);
             } else {
                 mPopup.setHeight(spaceForFullItems - mItemRowHeight + spaceForPartialItem +
                         padding.top + padding.bottom);
             }
         } else {
             mPopup.setHeight(ViewGroup.LayoutParams.WRAP_CONTENT);
         }
     }
+
+    private void runMenuItemEnterAnimations() {
+        AnimatorSet animation = new AnimatorSet();
+        AnimatorSet.Builder builder = null;
+
+        ViewGroup list = mPopup.getListView();
+        for (int i = 0; i < list.getChildCount(); i++) {
+            View view = list.getChildAt(i);
+            Object animatorObject = view.getTag(R.id.menu_item_enter_anim_id);
+            if (animatorObject != null) {
+                if (builder == null) {
+                    builder = animation.play((Animator) animatorObject);
+                } else {
+                    builder.with((Animator) animatorObject);
+                }
+            }
+        }
+
+        animation.start();
+    }
 }