MyWindowDemo

import java.awt.;
import java.awt.event.;
import java.io.*;
class MyWindowDemo
{
private Frame f;
private TextField tf;
private Button but;
private TextArea ta;

private Dialog d;
private Label lab;
private Button okBut;


MyWindowDemo()
{
	init();
}
public void init()
{
	f = new Frame("my window");
	f.setBounds(300,100,600,500);
	f.setLayout(new FlowLayout());

	tf = new TextField(60);

	but = new Button("转到");

	ta = new TextArea(25,70);


	d = new Dialog(f,"提示信息-self",true);
	d.setBounds(400,200,240,150);
	d.setLayout(new FlowLayout());
	lab = new Label();
	okBut = new Button("确定");

	d.add(lab);
	d.add(okBut);



	f.add(tf);
	f.add(but);
	f.add(ta);


	myEvent();
	f.setVisible(true);
}
private void  myEvent()
{

	okBut.addActionListener(new ActionListener()
	{
		public void actionPerformed(ActionEvent e)
		{
			d.setVisible(false);
		}
	});
	d.addWindowListener(new WindowAdapter()
	{
		public void windowClosing(WindowEvent e)
		{
			d.setVisible(false);
		}
	});

	tf.addKeyListener(new KeyAdapter()
	{
		public void keyPressed(KeyEvent e)
		{
			if(e.getKeyCode()==KeyEvent.VK_ENTER)
				showDir();
		}
	});


	but.addActionListener(new ActionListener()
	{
		public void actionPerformed(ActionEvent e)
		{
			showDir();
			
		}
	});

	f.addWindowListener(new WindowAdapter()
	{
		public void windowClosing(WindowEvent e)
		{
			System.exit(0);	
		}
	});
}

private void showDir()
{
	String dirPath = tf.getText();
			
	File dir = new File(dirPath);

	if(dir.exists() && dir.isDirectory())
	{
		ta.setText("");
		String[] names = dir.list();
		for(String name : names)
		{
			ta.append(name+"\r\n");
		}
	}
	else
	{
		String info = "您输入的信息："+dirPath+"是错误的。请重输";
		lab.setText(info);
		d.setVisible(true);
	}
}

public static void main(String[] args) 
{
	new MyWindowDemo();
}

}