question: private void notifyItemExpandedOrCollapsed ( int parentIndex , boolean isExpand ) { if ( mRecyclerViewList != null && ! mRecyclerViewList . isEmpty ( ) ) { RecyclerView recyclerView = mRecyclerViewList . get ( 0 ) ; BaseAdapterItem viewHolderForAdapterPosition = ( BaseAdapterItem ) recyclerView . findViewHolderForAdapterPosition ( parentIndex ) ; try { AbstractAdapterItem < Object > item = viewHolderForAdapterPosition . getItem ( ) ; if ( item != null && item instanceof AbstractExpandableAdapterItem ) { AbstractExpandableAdapterItem abstractExpandableAdapterItem = ( AbstractExpandableAdapterItem ) item ; abstractExpandableAdapterItem . onExpansionToggled ( isExpand ) ; } } catch ( Exception e ) { } } }
target:  notify item state changed