example5_1.java

书中的例题

/* JFrame类的简单示例*/
import javax.swing.*;
import java.awt.*;
import java.awt.event.*;
public class Example5_1 implements ActionListener
{
   public Example5_1()
   {
	  JFrame f = new JFrame("JFrame窗体示例");//JFrame对象实例化
	  Container contentPane = f.getContentPane();
	  JButton jbtn = new JButton("打开新窗体");
      contentPane.setLayout(new FlowLayout());
	  contentPane.add(jbtn);
	  jbtn.addActionListener(this);
	  f.setSize(200,200);
	  f.validate();
	  f.show();
	  f.addWindowListener(new WindowAdapter() {
         public void windowClosing(WindowEvent we)
	       {System.exit(0);}	    
       } );   
   }   
  public void actionPerformed(ActionEvent e)
	{ JFrame newf=new JFrame();
      newf.setSize(150,150);
	  newf.show();
   }
  public static void main(String[] args) 
	{  new Example5_1();	}
}