driver.java

Java程序设计(美) David D. Riley著 机械工业出版社 书籍配套 代码

/**	Author: David D. Riley
 *		Date: Jan, 2005
 *   Nested Circles Driver (Figure 6.18)
 */

public class Driver extends ThreeButtons {
	private ThreeButtonFrame  window;
	private ShadowedRedDot redDot;

	/**	post:	A window is displayed 
	 *			and a shadowed red dot is centered in the window
	 *			and the shadowed dot has a diameter of 200 pixels. 
	 */
	public Driver()   {
		window = new ThreeButtonFrame("Shadowed Red Dot");
		window.setLayout(null);
		redDot = new ShadowedRedDot( window );
		window.repaint();
	}
	
    /**	post:	the shadowed dot誷 diameter is enlarged by 20% */
	public void leftAction()   {
		redDot.zoom( 20.0 );
	}
	
	/**	post:	the shadowed dot誷 diameter is reset to 200 pixels */
	public void midAction()   {
		redDot.reset();
	}
	
				/**	post:	the shadowed dot誷 diameter is reduced by 30% */
	public void rightAction()   {
		redDot.zoom( -30.0 );
	}
}