请教师兄
请各位帮忙解释一下下面这段程序:
import java.awt.*;
import java.awt.event.*;
class MyButtonFrame extends Frame
{
public MyButtonFrame()
{
setTitle("测试");
setSize(300,200);
MyButtonPanel panel=new MyButtonPanel();
add(panel);
}
}
class MyButtonPanel extends Panel
{
public MyButtonPanel()
{
Button bButton=new Button("蓝色");
Button gButton=new Button("绿色");
Button eButton=new Button("退出");
add(bButton);
add(gButton);
add(eButton);
MyListenerAction bAction=new MyListenerAction(Color.blue);
MyListenerAction gAction=new MyListenerAction(Color.green);
MyListenerAction eAction=new MyListenerAction(Color.red);
bButton.addActionListener(bAction);
gButton.addActionListener(gAction);
eButton.addActionListener(eAction);
}
private class MyListenerAction implements ActionListener
{
private Color bgColor;
public MyListenerAction(Color c)
{
bgColor=c;
}
public void actionPerformed(ActionEvent event)
{
setBackground(bgColor);
repaint();
if(event.getActionCommand()=="退出")
System.exit(0);
}
}
}
public class myButton
{
public static void main(String args[])
{
MyButtonFrame frm=new MyButtonFrame();
frm.show();
}
}