private void startDrag() {
Container parent = getParent();
if (paintBackgroundUnderDragRect) { // 2007/02/27
if (desktopImage == null || (desktopImage.getWidth() != parent.getWidth()) || (desktopImage.getHeight() != parent.getHeight())) {
desktopImage = (BufferedImage) parent.createImage(parent.getWidth(),
parent.getHeight());
subImage = null;
}
Graphics g = desktopImage.getGraphics();
parent.paint(g);