movecubebutton.java

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

// Figure 8.30

import java.awt.event.ActionEvent;  
public class MoveCubeButton extends EventButton  {
	private Cube theCube;

	/**	pre:	d != null  <br>
	 *	post:	theCube == d
	 *			and  getX() == x  and  getY() == y  
	 *			and  getWidth() == 100  and  getHeight() == 30  
	 */
   public MoveCubeButton( int x, int y, Cube d )  {
		super( "MOVE" );
		setBounds(x, y, 100, 30);
		theCube = d;
   }

	/**	pre:	theCube != null  <br>
	 *	post:	theCube.getX() == theCube.getX()@pre + 5  
	 *			and theCube.getY() = theCube.getY()@pre + 5   
	 */
	public void actionPerformed( ActionEvent e )   {
		theCube.setLocation( theCube.getX()+5, theCube.getY()+5 );
	}
}