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

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

/** PolkaDot Program  (Figure 10.14)
 *  Author: David Riley
 *  Date: January, 2005
 */
public class Driver  {
	private JFrame window;

	public Driver()   {
		int  yCount, xCount;
		Oval dot;
		Color rowColor;
		window = new JFrame("Polkadots");
		window.setBounds(10, 10, 200, 200);
		window.setVisible(true);
		window.setLayout(null);
		
		yCount = 0;
		while ( yCount != 12 )   {
			rowColor = new Color(yCount/13.0f, yCount/13.0f, yCount/13.0f);
				// rowColor is gray an intensity of yCount/13.
				//      (0.0f is black and 1.0f is white)
			xCount = 0;
			while ( xCount != 8 )   {
				dot = new Oval(xCount*25, yCount*15, 10, 10);
				dot.setBackground(rowColor);
				window.add(dot, 0);
				xCount++;
			}
			yCount++;
		}
		window.repaint();
	}
}