code: private void recoverDraggablePanelState(Bundle savedInstanceState) {
      final DraggableState draggableState =
          (DraggableState) savedInstanceState.getSerializable(DRAGGABLE_PANEL_STATE);
      if (draggableState == null) {
        draggablePanel.setVisibility(View.GONE);
        return;
      }
      updateDraggablePanelStateDelayed(draggableState);
    }
docs: Get the DraggablePanelState from the saved bundle, modify the DraggablePanel visibility to
  GONE
  and apply the
  DraggablePanelState to recover the last graphic state.