OnChildDraw.java

if (dX > 0) { // Swiping to the right
    background.setBounds(itemView.getLeft(), itemView.getTop(),
            itemView.getLeft() + ((int) dX) + backgroundCornerOffset,
            itemView.getBottom());

} else if (dX < 0) { // Swiping to the left
    background.setBounds(itemView.getRight() + ((int) dX) - backgroundCornerOffset,
            itemView.getTop(), itemView.getRight(), itemView.getBottom());
} else { // view is unSwiped
    background.setBounds(0, 0, 0, 0);
}
background.draw(c);