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Swing ContainerListener接口

用於接收容器事件的接口ContainerListener。容器事件類需要實現這個接口。

類聲明

以下是聲明 java.awt.event.ContainerListener接口:

public interface ContainerListener
extends EventListener

接口方法

S.N. 方法 & 描述
1 void componentAdded(ContainerEvent e) 
Invoked when a component has been added to the container.
2 void componentRemoved(ContainerEvent e) 
Invoked when a component has been removed from the container.

方法繼承

This class inherits methods from the following interfaces:

  • java.awt.event.EventListener

ContainerListener 例子

選擇使用任何編輯器創建以下java程序在 D:/ > SWING > com > yiibai > gui >

SwingListenerDemo.java
package com.yiibai.gui;

import java.awt.*;
import java.awt.event.*;
import javax.swing.*;

public class SwingListenerDemo {
   private JFrame mainFrame;
   private JLabel headerLabel;
   private JLabel statusLabel;
   private JPanel controlPanel;

   public SwingListenerDemo(){
      prepareGUI();
   }

   public static void main(String[] args){
      SwingListenerDemo  swingListenerDemo = new SwingListenerDemo();  
      swingListenerDemo.showContainerListenerDemo();
   }

   private void prepareGUI(){
      mainFrame = new JFrame("Java SWING Examples");
      mainFrame.setSize(400,400);
      mainFrame.setLayout(new GridLayout(3, 1));

      headerLabel = new JLabel("",JLabel.CENTER );
      statusLabel = new JLabel("",JLabel.CENTER);        

      statusLabel.setSize(350,100);
      mainFrame.addWindowListener(new WindowAdapter() {
         public void windowClosing(WindowEvent windowEvent){
	        System.exit(0);
         }        
      });    
      controlPanel = new JPanel();
      controlPanel.setLayout(new FlowLayout());

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

   private void showContainerListenerDemo(){
      headerLabel.setText("Listener in action: ContainerListener");      

      JPanel panel = new JPanel();      
      panel.setBackground(Color.magenta);            
      panel.addContainerListener(new CustomContainerListener());  

      JLabel msglabel 
      = new JLabel("Welcome to TutorialsPoint SWING Tutorial."
      ,JLabel.CENTER);        
      panel.add(msglabel);

      controlPanel.add(panel);
      mainFrame.setVisible(true);  
   }

   class CustomContainerListener implements ContainerListener {
      public void componentAdded(ContainerEvent e) {
         statusLabel.setText(statusLabel.getText() 
         + e.getComponent().getClass().getSimpleName() + " added. ");
      }

      public void componentRemoved(ContainerEvent e) {
         statusLabel.setText(statusLabel.getText() 
         + e.getComponent().getClass().getSimpleName() + " removed. ");
      }
   }

}

編譯程序,使用命令提示符。到 D:/ > SWING 然後輸出以下命令。

D:SWING>javac comyiibaiguiSwingListenerDemo.java

如果冇有錯誤出現,這意味著編譯成功。使用下麵的命令來運行程序。

D:SWING>java com.yiibai.gui.SwingListenerDemo

驗證下麵的輸出

SWING ContainerListener