java:图形化界面awt基本实例

<pre name="code" class="java">/**创建一个图形化界面在TextField中输入目录，就会再TextField中显示该目录下的文件*/import java.io.*;import java.awt.*;import java.awt.event.*;class TestFileFrame{public static void main(String[] args) throws Exception{//创建窗体Frame f = new Frame("打开文件");f.setSize(400, 500);   //设置大小f.setLocation(300,250);  //设置位置f.setLayout(new FlowLayout());  //设置布局方式//创建部件TextField tf = new TextField();  //单行文本TextArea ta = new TextArea();   //多行文本Button but = new Button("打开");  //按钮tf.setColumns(40);ta.setColumns(45);ta.setRows(25);f.add(tf);f.add(but);f.add(ta);f.setVisible(true);//在按钮上添加活动监听//单击按钮，在TextArea中显示TextField目录下的文件but.addActionListener(new ActionListener(){public void actionPerformed(ActionEvent e){String text = tf.getText();File file = new File(text);if(file.isDirectory()){ta.setText("");String[] str = file.list();for(String s: str){ta.append(s +"\r\n");}}}});//在文本框中添加键盘监听//按下回车键，在TextArea中显示TextField目录下的文件tf.addKeyListener(new KeyAdapter(){public void keyPressed(KeyEvent e){if(e.getKeyCode() == e.VK_ENTER){String text = tf.getText();File file = new File(text);if(file.isDirectory()){ta.setText("");String[] str = file.list();//只显示.java文件for(String s: str){if(s.endsWith(".java"))ta.append(s +"\r\n");}}}}});//添加窗口监听f.addWindowListener(new WindowAdapter(){public void windowClosing(WindowEvent e){f.setVisible(false);System.exit(0);}});}}