private void adjustAllItems() {
        final int first = getFirstVisiblePosition();
        final int last = getLastVisiblePosition();

        int begin = Math.max(0, getHeaderViewsCount() - first);
        int end = Math.min(last - first, getCount() - 1 - getFooterViewsCount() - first);

        for (int i = begin; i <= end; ++i) {
            View v = getChildAt(i);
            if (v != null) {
                adjustItem(first + i, v, false);
            }
        }
    }
Set the width of each drag scroll region by specifying
a fraction of the ListView height.

@param upperFrac Fraction of ListView height for up-scroll bound.
Capped at 0.5f.
@param lowerFrac Fraction of ListView height for down-scroll bound.
Capped at 0.5f.
third_party/DragSortListView/src/com/mobeta/android/dslv/DragSortListView.java