Android ExpandableListView using animation

Question

I\'m using

Answer 1

@idunnololz solution works great. however i would like to add some code to collapse previously expanded group.

private int previousGroup=-1;

    listView.setOnGroupClickListener(new OnGroupClickListener() {

        @Override
        public boolean onGroupClick(ExpandableListView parent, View v, int groupPosition, long id) {
            // We call collapseGroupWithAnimation(int) and
            // expandGroupWithAnimation(int) to animate group 
            // expansion/collapse.
            if (listView.isGroupExpanded(groupPosition)) {
                listView.collapseGroupWithAnimation(groupPosition);
                previousGroup=-1;
            } else {
                listView.expandGroupWithAnimation(groupPosition);
                if(previousGroup!=-1){
                    listView.collapseGroupWithAnimation(previousGroup); 
                }
                previousGroup=groupPosition;
            }

            return true;
        }

    });