@Override
 public void onInvalidated() {
   super.onInvalidated();
   mDataValid = false;
   notifyDataSetChanged();
   // There is no notifyDataSetInvalidated() method in RecyclerView.Adapter
 }
 /** Notifies observers about invalidating data */
 protected void notifyDataInvalidatedEvent() {
   if (datasetObservers != null) {
     for (DataSetObserver observer : datasetObservers) {
       observer.onInvalidated();
     }
   }
 }
    @Override
    public void onInvalidated() {
      Log.i(LOG_TAG, "onInvalidated");
      super.onInvalidated();

      resetList();
      reloadAdapter();
    }
 @Override
 public void onInvalidated() {
   super.onInvalidated();
   valid = false;
   notifyDataSetChanged();
 }
 @Override
 public void onInvalidated() {
   Log.i(TAG, "WorkspaceDataSetObserver::onInvalidated");
   super.onInvalidated();
 }
 @Override
 public void onInvalidated() {
   super.onInvalidated();
   mHasInvalidated = true;
 }