private void reprioritizeDownloads() {
   int lastVisibleItem = listView.getLastVisiblePosition();
   if (lastVisibleItem >= 0) {
     int firstVisibleItem = listView.getFirstVisiblePosition();
     adapter.prioritizeViewRange(
         firstVisibleItem, lastVisibleItem, PROFILE_PICTURE_PREFETCH_BUFFER);
   }
 }
  void updateAdapter(SimpleGraphObjectCursor<T> data) {
    if (adapter != null) {
      // As we fetch additional results and add them to the table, we do not
      // want the items displayed jumping around seemingly at random, frustrating the user's
      // attempts at scrolling, etc. Since results may be added anywhere in
      // the table, we choose to try to keep the first visible row in a fixed
      // position (from the user's perspective). We try to keep it positioned at
      // the same offset from the top of the screen so adding new items seems
      // smoother, as opposed to having it "snap" to a multiple of row height

      // We use the second row, to give context above and below it and avoid
      // cases where the first row is only barely visible, thus providing little context.
      // The exception is where the very first row is visible, in which case we use that.
      View view = listView.getChildAt(1);
      int anchorPosition = listView.getFirstVisiblePosition();
      if (anchorPosition > 0) {
        anchorPosition++;
      }
      GraphObjectAdapter.SectionAndItem<T> anchorItem = adapter.getSectionAndItem(anchorPosition);
      final int top =
          (view != null
                  && anchorItem.getType() != GraphObjectAdapter.SectionAndItem.Type.ACTIVITY_CIRCLE)
              ? view.getTop()
              : 0;

      // Now actually add the results.
      boolean dataChanged = adapter.changeCursor(data);

      if (view != null && anchorItem != null) {
        // Put the item back in the same spot it was.
        final int newPositionOfItem =
            adapter.getPosition(anchorItem.sectionKey, anchorItem.graphObject);
        if (newPositionOfItem != -1) {
          listView.setSelectionFromTop(newPositionOfItem, top);
        }
      }

      if (dataChanged && onDataChangedListener != null) {
        onDataChangedListener.onDataChanged(PickerFragment.this);
      }
    }
  }