driver.java

来自「Java程序设计(美) David D. Riley著 机械工业出版社 书籍配套」· Java 代码 · 共 38 行

import javax.swing.JFrame;
import java.awt.*;

/** Program to print widths of parent Containers (Figure 14.12)
 *  Author: David Riley
 *  Date: January, 2005
 */
public class Driver  {

	public Driver()   {
		JFrame win = new JFrame("Ancestor Containers");
        win.setBounds(10, 10, 400, 70);
		win.setVisible(true);
        win.setLayout(null);
		Rectangle outerRect = new Rectangle( 0, 0, 350, 40 );
		outerRect.setBackground(Color.blue);
		win.add(outerRect, 0);
		Rectangle midRect = new Rectangle( 0, 0, 250, 30 );
		midRect.setBackground(Color.green);
		outerRect.add(midRect, 0);
		Rectangle innerRect = new Rectangle( 0, 0, 100, 20 );
		innerRect.setBackground(Color.red);
		midRect.add(innerRect, 0);
		win.repaint();
		displayAncestorWidths( innerRect, win.getContentPane() );
	}
	
	/**	post:	all ancestor widths are displayed 
	 *				- most distant ancestors first  
	 */
	private void displayAncestorWidths(Component c, Container pane)   {
		if (c != pane  &&  c != null)  
			displayAncestorWidths( c.getParent(), pane );
		System.out.println( "Width: " + c.getWidth() );
		
	}
}