beautifulgrid.java

时间函数控制的 模拟屏保

/**程序线程通过使用Timer类控制动画
 *Timer类是通过固定频率调用actionPerformed方法
 *注意：如果你的编译器是j2sdk1.5.0版本，没有这样的效果
 *只能使用j2sdk1.4.x版本。
 */
import java.awt.Graphics;
import java.awt.Color;
import javax.swing.JPanel;
import javax.swing.JFrame;
import javax.swing.Timer;
import java.awt.Dimension;
import java.awt.event.*;

public class BeautifulGrid extends JFrame  implements ActionListener
{  
  protected static Point[] point = new Point[2];
  protected static Point[] span = new Point[2];
  
  protected static Color color = null;
  protected static int red = 0;
  protected static int green = 0;
  protected static int blue = 0;
   
  protected Timer timer = null;
  
  // 构造方法
  public BeautifulGrid()
  {  	
  	point[0] = new Point(50,50);
  	point[1] = new Point(550,400);
  	
  	span[0] = new Point(3,5);
  	span[1] = new Point(-5,-3);
  	
    getContentPane().add(new RectPanel());
    
    // 创建一个Timer对象，该对象以50毫秒的频率调用actionPerformed方法
    timer = new Timer(50,this);
  	timer.start();
  }

  public void actionPerformed(ActionEvent e)
  {
  	repaint();
  }
  
  //面板类
  class RectPanel extends JPanel    
  {			
   	public void paintComponent(Graphics g)
   	{ 		  			
		green = point[1].x%255; 
     	blue = point[1].y%255;
     	g.setColor(new Color(255, green, blue));
     			
     	g.drawLine(point[0].x,point[0].y,point[1].x,point[1].y);
   		
     	for(int i=0; i<2; i++)
     	{
     		point[i].x += span[i].x;
     		point[i].y += span[i].y;
     			
     		if(point[i].x <= 5 || point[i].x >= 630) span[i].x = -span[i].x;
     		if(point[i].y <= 5 || point[i].y >= 490) span[i].y = -span[i].y; 
     	}
   	}
 }
	
 //坐标点类
 class Point 
 {
	protected int x =0;
	protected int y =0;
		
	public Point(int x, int y)
	{
		this.x = x;
		this.y = y;
	} 
  }
	
  // Main 方法
  public static void main(String[] args)
  {
    JFrame.setDefaultLookAndFeelDecorated(true);
    BeautifulGrid frame = new BeautifulGrid();
    frame.setTitle("顶尖设计师杰作－－多彩的网格世界");
    frame.setResizable(false);
    frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
    frame.setSize(640,500);
    frame.setVisible(true);
  }
}