mybutton2.java

来自「这个是JAVA程序基础书上第六章处理异常源代码」· Java 代码 · 共 63 行

import java.awt.*;
import java.awt.event.*;
public class MyButton2{
	Frame f;
    Button b1;
    Button b2;
	TextArea ta;

	public MyButton2(){
		Frame f = new Frame();
	    b1 = new Button("Button 1");
	    b2 = new Button("Button 2");
	    ta = new TextArea(null, 6, 40);
	    
	    MyActionImpl ma = new MyActionImpl();
	    MyFocusImpl mf = new MyFocusImpl();		
	    
	    f.addWindowListener(new MyWindowAdapter());
	    b1.addActionListener(ma);
	    b2.addActionListener(ma);
	    b1.addFocusListener(mf);
	    b2.addFocusListener(mf);
	    
	    f.setLayout(new FlowLayout());
	    f.setSize(300, 200);
	    f.add(b1);
	    f.add(b2);
	    f.add(ta);
	    f.setVisible(true);
	}
	public static void main(String[] args){
		MyButton2 mb = new MyButton2();
    }
	class MyFocusImpl implements FocusListener{
		public void focusGained(FocusEvent e){
			if (e.getSource()==b1)
				ta.append("\nButton1 Got Focus !");
			else
				ta.append("\nButton2 Got Focus !");
		}
		public void focusLost(FocusEvent e){
			if (e.getSource()==b1)
				ta.append("\nButton1 Lost Focus !");
			else
				ta.append("\nButton2 Lost Focus !");
		}
	}
    class MyActionImpl implements ActionListener{
	  public void actionPerformed(ActionEvent e){
	 	if (e.getSource()==b1) 
			ta.append("\nButton1 Was Clicked !");
		else
			ta.append("\nButton2 Was Clicked !");
	  }
    }
	//注意这里对窗口关闭的处理与前面一个例子的不同
	class MyWindowAdapter extends WindowAdapter{
		public void windowClosing(WindowEvent e){
			System.exit(0);
		}
	}	
}