Swing ComponentListener介面

處理ComponentEvent的類應該實現此介面。該類的對象必須使用組件註冊。可以使用addComponentListener()方法註冊該對象。引發組件事件僅供參考。

介面聲明

以下是java.awt.event.ComponentListener介面的聲明 -

public interface ComponentListener
   extends EventListener

介面方法

方法繼承

此介面從以下介面繼承方法 -

• java.awt.EventListener

ComponentListener示例

使用編輯器創建以下Java程式：ComponentListenerDemo.java

package com.zaixian.swing.listener;

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

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

   public ComponentListenerDemo(){
      prepareGUI();
   }
   public static void main(String[] args){
       ComponentListenerDemo  swingListenerDemo = new ComponentListenerDemo();
      swingListenerDemo.showComponentListenerDemo();
   }
   private void prepareGUI(){
      mainFrame = new JFrame("Java SWING ComponentListener示例(xuhuhu.com)");
      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 showComponentListenerDemo(){
      headerLabel.setText("Listener in action: ComponentListener");

      JPanel panel = new JPanel();
      panel.setBackground(Color.BLUE);

      JLabel msglabel =
      new JLabel("歡迎您來到許虎虎SWING教學~",JLabel.CENTER);
      panel.add(msglabel);

      msglabel.addComponentListener(new CustomComponentListener());
      controlPanel.add(panel);
      mainFrame.setVisible(true);
   }
   class CustomComponentListener implements ComponentListener {
      public void componentResized(ComponentEvent e) {
         statusLabel.setText(statusLabel.getText()
            + e.getComponent().getClass().getSimpleName() + " resized. ");
      }
      public void componentMoved(ComponentEvent e) {
         statusLabel.setText(statusLabel.getText()
            + e.getComponent().getClass().getSimpleName() + " moved. ");
      }
      public void componentShown(ComponentEvent e) {
         statusLabel.setText(statusLabel.getText()
            + e.getComponent().getClass().getSimpleName() + " shown. ");
      }
      public void componentHidden(ComponentEvent e) {
         statusLabel.setText(statusLabel.getText()
            + e.getComponent().getClass().getSimpleName() + " hidden. ");
      }
   }
}

當執行上面示例代碼時，得到以下結果：