question: public void collapseAllParents ( ) { if ( mDataList != null && ! mDataList . isEmpty ( ) ) { ArrayList < Object > expandableListItems = getParents ( true ) ; if ( expandableListItems != null && ! expandableListItems . isEmpty ( ) ) { final int expandedItemSize = expandableListItems . size ( ) ; if ( expandedItemSize > 0 ) { for ( int i = 0 ; i < expandedItemSize ; i ++ ) { Object o = expandableListItems . get ( i ) ; int indexOf = mDataList . indexOf ( o ) ; if ( indexOf >= 0 ) collapseParentListItem ( ( ExpandableListItem ) o , indexOf , false ) ; } } } } }
target:  Collapses all parents in the list.