import java.awt.event.*; 
import javax.swing.*; 
import java.awt.*; 
public class ComponentEvents implements ActionListener { 

    JFrame jf = new JFrame();
    JButton b1=new JButton("改变框架的主题."); 
    JButton b2=new JButton("还原框架的主题"); 
    JButton btnColor=new JButton("改变按钮的颜色"); 
    JButton btnRestore=new JButton("还原按钮颜色"); 
    //Graphics gra=new Graphics(); 
    Color color=btnColor.getBackground(); 
    public ComponentEvents () { 
        jf.setTitle("ComponentEvents");
        jf.setSize(600,300); 
        jf.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE); 
        b1.addActionListener(this); 
        b2.addActionListener(this); 
        btnColor.addActionListener(this); 
        btnRestore.addActionListener(this); 
        b1.setBounds(10,20,150,20); 
        b2.setBounds(160,20,150,20); 
        btnColor.setBounds(10,60,150,20); 
        btnRestore.setBounds(160,60,150,20); 
        JPanel pane=new JPanel(); 
        pane.setLayout(null); 
        pane.add(b1); 
        pane.add(b2); 
        pane.add(btnColor); 
        pane.add(btnRestore); 
        jf.add(pane); 
        jf.setVisible(true); 
    } 
    public void actionPerformed(ActionEvent evt) { 
        Object source=evt.getSource(); 
        if(source==b1) 
            jf.setTitle("dkf"); 
        else if(source==b2) 
            jf.setTitle("ComponentEvents"); 
        else if (source==btnColor) 
        { 
            btnColor.setBackground(Color.orange); 
        } 
        else if (source==btnRestore) 
        { 
            btnColor.setBackground(color); 
        } 
    } 
//    public void paint(Graphics g) 
//    { 
//        b1.setBounds(10,20,150,20); 
//        b2.setBounds(160,20,150,20); 
//        btnColor.setBounds(10,60,150,20); 
//        btnRestore.setBounds(160,60,150,20); 
//        g.drawLine(10,170,500,170); 
//        //repaint(); 
//    } 
    public static void main(String[] args) 
    { 
        ComponentEvents comevt= new ComponentEvents(); 
    } 
}