@Override
    public void toggle() {
        View child = getChildAt(0);
        if (child instanceof Checkable)
            ((Checkable) child).toggle();
    }
Lightweight ViewGroup that wraps list items obtained from user's
ListAdapter. ItemView expects a single child that has a definite
height (i.e. the child's layout height is not MATCH_PARENT).
The width of
ItemView will always match the width of its child (that is,
the width MeasureSpec given to ItemView is passed directly
to the child, and the ItemView measured width is set to the
child's measured width). The height of ItemView can be anything;
the 


The purpose of this class is to optimize slide
shuffle animations.
third_party/DragSortListView/src/com/mobeta/android/dslv/DragSortItemViewCheckable.java