trafficlightpanel.java

一个模拟交通灯的JAVA源代码

//******************************************************************************
//  trafficlight.java                     Author:lsh
//
// 画出交通灯并用按钮改变灯的颜色
//******************************************************************************
import javax.swing.*;
import java.awt.*;
import java.awt.event.*;

class trafficlightPanel extends JPanel
{
    final int BASEX=200;
	final int BASEY=50;
	private JButton change;
	private JPanel buttonPanel;
	private JLabel label;
	private int count=3;
	//---------------------------------------------------------------
	//GUI编程
	//---------------------------------------------------------------
	public trafficlightPanel()
	{
	
		setBackground(Color.cyan);
		setPreferredSize(new Dimension(900,600));
		
		change=new JButton("change");
		ButtonListener listener=new ButtonListener();
		change.addActionListener(listener);
		
		buttonPanel=new JPanel();
		buttonPanel.setPreferredSize(new Dimension(100,50));
		buttonPanel.setBackground(Color.blue);
		buttonPanel.add(change);
		
	    add(buttonPanel);
    }	
	//----------------------------------------------------------------
	//画图并加颜色
	//----------------------------------------------------------------
	public void paintComponent(Graphics page)	
	{
		super.paintComponent(page);
		
		if(count%3==0)
        {
        	page.setColor(Color.lightGray);
	        page.fillOval(BASEX-98,BASEY+35,250,80);
	        page.fillRect(BASEX+15,BASEY+110,30,350);
	        page.fillRect(BASEX-160,BASEY+450,400,10);
	        
        	page.setColor(Color.red);
	        page.fillOval(BASEX-60,BASEY+50,50,50);
        	page.setColor(Color.gray);
	        page.fillOval(BASEX,BASEY+50,50,50);
	        page.fillOval(BASEX+60,BASEY+50,50,50);
	    }
	    
	    if(count%3==1)
	    {
	        page.setColor(Color.lightGray);
	        page.fillOval(BASEX-98,BASEY+35,250,80);
	        page.fillRect(BASEX+15,BASEY+110,30,350);
	        page.fillRect(BASEX-160,BASEY+450,400,10);
	        
	        page.setColor(Color.green);
	        page.fillOval(BASEX,BASEY+50,50,50);
	        page.setColor(Color.gray);
	        page.fillOval(BASEX-60,BASEY+50,50,50);
	        page.fillOval(BASEX+60,BASEY+50,50,50);
	    }
	    
	    if(count%3==2)
	    {
	        page.setColor(Color.lightGray);
	        page.fillOval(BASEX-98,BASEY+35,250,80);
	        page.fillRect(BASEX+15,BASEY+110,30,350);
	        page.fillRect(BASEX-160,BASEY+450,400,10);
	        
	        page.setColor(Color.yellow);
	        page.fillOval(BASEX+60,BASEY+50,50,50);
	        page.setColor(Color.gray);
	        page.fillOval(BASEX,BASEY+50,50,50);
	        page.fillOval(BASEX-60,BASEY+50,50,50);
        }
	}
	//--------------------------------------------------------------
	//监听
	//--------------------------------------------------------------
    private class ButtonListener implements ActionListener
	{
		public void actionPerformed(ActionEvent event)
		{
			count++;
			repaint();
			
		}
	}
}