AWT » WindowListener 介面

WindowListener 介面

WindowEvent類的物件應該實現這個介面。類處理一個元件必須註冊。使用addWindowListener（）方法，該物件可以被註冊。

介面宣告

以下是宣告的java.awt.event.WindowListener介面：

public interface WindowListener
   extends EventListener

介面中的方法

S.N. 方法＆說明
1 void windowActivated(WindowEvent e) 
Invoked when the Window is set to be the active Window.
2 void windowClosed(WindowEvent e) 
Invoked when a window has been closed as the result of calling dispose on the window.
3 void windowClosing(WindowEvent e) 
Invoked when the user attempts to close the window from the window's system menu.
4 void windowDeactivated(WindowEvent e) 
Invoked when a Window is no longer the active Window.
5 void windowDeiconified(WindowEvent e) 
Invoked when a window is changed from a minimized to a normal state.
6 void windowIconified(WindowEvent e) 
Invoked when a window is changed from a normal to a minimized state.
7 void windowOpened(WindowEvent e) 
Invoked the first time a window is made visible.

繼承的方法

這個介面繼承的方法從下面的介面：

  • java.awt.EventListener

WindowListener範例

選擇使用任何編輯器建立以下java程式 D:/ > AWT > com > yiibai > gui >

AwtListenerDemo 
package com.yiibai.gui;

import java.awt.*;
import java.awt.event.*;

public class AwtListenerDemo {
   private Frame mainFrame;
   private Label headerLabel;
   private Label statusLabel;
   private Panel controlPanel;

   public AwtListenerDemo(){
      prepareGUI();
   }

   public static void main(String[] args){
      AwtListenerDemo  awtListenerDemo = new AwtListenerDemo();  
      awtListenerDemo.showWindowListenerDemo();
   }

   private void prepareGUI(){
      mainFrame = new Frame("Java AWT Examples");
      mainFrame.setSize(400,400);
      mainFrame.setLayout(new GridLayout(3, 1));
      mainFrame.addWindowListener(new WindowAdapter() {
         public void windowClosing(WindowEvent windowEvent){
            System.exit(0);
         }        
      });    
   
      headerLabel = new Label();
      headerLabel.setAlignment(Label.CENTER);
      statusLabel = new Label();        
      statusLabel.setAlignment(Label.CENTER);
      statusLabel.setSize(350,100);

      controlPanel = new Panel();
      controlPanel.setLayout(new FlowLayout());

      mainFrame.add(headerLabel);
      mainFrame.add(controlPanel);
      mainFrame.add(statusLabel);
      mainFrame.setVisible(true);  
   }

   private void showWindowListenerDemo(){
      headerLabel.setText("Listener in action: WindowListener");      

      Button okButton = new Button("OK");

      aboutFrame = new Frame();
      aboutFrame.setSize(300,200);;
      aboutFrame.setTitle("WindowListener Demo");
      aboutFrame.addWindowListener(new CustomWindowListener());

      Label msgLabel = new Label("Welcome to yiibai.");
      msgLabel.setAlignment(Label.CENTER);
      msgLabel.setSize(100,100);
      aboutFrame.add(msgLabel);
      aboutFrame.setVisible(true);
   }

   class CustomWindowListener implements WindowListener {
      public void windowOpened(WindowEvent e) {
      }

      public void windowClosing(WindowEvent e) {
         aboutFrame.dispose();      
      }
      
      public void windowClosed(WindowEvent e) {
      }

      public void windowIconified(WindowEvent e) {
      }

      public void windowDeiconified(WindowEvent e) {
      }

      public void windowActivated(WindowEvent e) {
      }

      public void windowDeactivated(WindowEvent e) {
      }
   }   
}

編譯程式，使用命令提示字元。到 D:/ > AWT 然後鍵入以下命令。

D:AWT>javac comyiibaiguiAwtListenerDemo.java

如果沒有錯誤出現，這意味著編譯成功。使用下面的命令來執行程式。

D:AWT>java com.yiibai.gui.AwtListenerDemo

驗證下面的輸出

AWT WindowListener