expandGroup can now animate

 Add a boolean to have expandGroup animate the same as
 performItemClick does

Change-Id: I652c6fa8f9a7b527572337b11900d653b5285352

2 files changed, 26 insertions, 2 deletions

diff --git a/api/current.txt b/api/current.txt
index b88ef3a4626f..212e012be540 100644
--- a/api/current.txt
+++ b/api/current.txt
@@ -24010,6 +24010,7 @@ package android.widget {
     ctor public ExpandableListView(android.content.Context, android.util.AttributeSet, int);
     method public boolean collapseGroup(int);
     method public boolean expandGroup(int);
+    method public boolean expandGroup(int, boolean);
     method public android.widget.ExpandableListAdapter getExpandableListAdapter();
     method public long getExpandableListPosition(int);
     method public int getFlatListPosition(long);
diff --git a/core/java/android/widget/ExpandableListView.java b/core/java/android/widget/ExpandableListView.java
index f8623686d277..ead9b4f977a9 100644
--- a/core/java/android/widget/ExpandableListView.java
+++ b/core/java/android/widget/ExpandableListView.java
@@ -599,12 +599,35 @@ public class ExpandableListView extends ListView {
      *         was already expanded, this will return false)
      */
     public boolean expandGroup(int groupPos) {
-        boolean retValue = mConnector.expandGroup(groupPos);
+       return expandGroup(groupPos, false);
+    }
+
+    /**
+     * Expand a group in the grouped list view
+     *
+     * @param groupPos the group to be expanded
+     * @param animate true if the expanding group should be animated in
+     * @return True if the group was expanded, false otherwise (if the group
+     *         was already expanded, this will return false)
+     */
+    public boolean expandGroup(int groupPos, boolean animate) {
+        PositionMetadata pm = mConnector.getFlattenedPos(ExpandableListPosition.obtain(
+                ExpandableListPosition.GROUP, groupPos, -1, -1));
+        boolean retValue = mConnector.expandGroup(pm);
 
         if (mOnGroupExpandListener != null) {
             mOnGroupExpandListener.onGroupExpand(groupPos);
         }
-        
+
+        if (animate) {
+            final int groupFlatPos = pm.position.flatListPos;
+
+            final int shiftedGroupPosition = groupFlatPos + getHeaderViewsCount();
+            smoothScrollToPosition(shiftedGroupPosition + mAdapter.getChildrenCount(groupPos),
+                    shiftedGroupPosition);
+        }
+        pm.recycle();
+
         return retValue;
     }