初学java之事件响应（结合接口来设置在同一个界面上！）

 1 package wahaha;

 2 

 3 public class test_1 {

 4     public static void main( String args[] )

 5     {

 6         WindowActionEvent win = new WindowActionEvent();

 7         PoliceListen police = new PoliceListen(); //创建监视器

 8         win.setMyCommandListener(police);

 9         win.setBounds(100, 100, 460, 360);

10         win.setTitle("处理ACtionEvent事件");

11     }

12 }

main_class

 1 package wahaha;

 2 

 3 import javax.swing.*;

 4 import java.awt.*;

 5 

 6 public class WindowActionEvent extends JFrame

 7 {

 8     

 9     JTextField inputText ;

10     JTextArea testshow ;

11     JButton button ;

12     MyCommandListener listenner ;

13     

14     public WindowActionEvent()

15     {

16         init();

17         setVisible(true);

18         setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);

19     }

20    

21     void init()

22     {

23       setLayout(new FlowLayout());

24       inputText =new JTextField(10);

25       button =new JButton("确定");

26       testshow = new JTextArea(9,30); 

27       add(inputText);

28       add(button); 

29       add(new JScrollPane(testshow));

30     }

31     

32     void setMyCommandListener(MyCommandListener listener)

33     {

34         this.listenner = listener ;

35         listener.setJTextArea(testshow);

36         listener.setJTextField(inputText);

37                                     //inputText是事件源，listener是监视器      

38         button.addActionListener(listener) ;

39                                     //button是事件源 ，listener是监视器

40     }

41 }

demo

 1  package wahaha;

 2 

 3 //设置一个接口 implements/interface/extends

 4  

 5 import javax.swing.* ;

 6 import java.awt.event.* ;

 7 

 8 public interface MyCommandListener extends ActionListener    //子接口多给出了2个方法

 9 {

10    public void setJTextField(JTextField text);

11    public void setJTextArea(JTextArea area);

12 }

View Code

 1   

 2   package wahaha;

 3 

 4   import javax.swing.*;

 5   import java.awt.event.*;

 6 

 7   public class PoliceListen implements MyCommandListener

 8   {

 9     JTextField textInput ;

10     JTextArea textshow ;

11    

12    public void setJTextField( JTextField text )

13    {

14      textInput = text ;

15    }

16   

17    public void setJTextArea(JTextArea area)

18    {

19        textshow = area;         

20    }

21    

22    public void actionPerformed( ActionEvent e)

23    {    

24        String str=textInput.getText();

25        textshow.append(str+"的长度："+str.length()+"\n");

26    }

27   }

View Code