View findOpenDrawer() {
        final int childCount = getChildCount();
        for (int i = 0; i < childCount; i++) {
            final View child = getChildAt(i);
            final LayoutParams childLp = (LayoutParams) child.getLayoutParams();
            if ((childLp.openState & LayoutParams.FLAG_IS_OPENED) == 1) {
                return child;
            }
        }
        return null;
    }
@return the absolute gravity of the child drawerView, resolved according
to the current layout direction
app/src/main/java/com/sunnyweather/android/ui/customerUIs/HomeDrawerLayout.java