ContainerListener
接口用于接收容器事件,处理容器事件的类需要实现此接口。
接口声明
以下是java.awt.event.ContainerListener
接口的声明 -
public interface ContainerListener
extends EventListener
接口方法
编号 | 方法 | 描述说明 |
---|---|---|
1 | void componentAdded(ContainerEvent e) |
将组件添加到容器时调用。 |
2 | void componentRemoved(ContainerEvent e) |
从组件中删除组件时调用。 |
方法继承
该类从以下接口继承方法 -
java.awt.event.EventListener
ContainerListener示例
使用编辑器创建以下Java程序:ContainerListenerDemo.java
package com.yiibai.swing.listener;
import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
public class ContainerListenerDemo {
private JFrame mainFrame;
private JLabel headerLabel;
private JLabel statusLabel;
private JPanel controlPanel;
public ContainerListenerDemo() {
prepareGUI();
}
public static void main(String[] args) {
ContainerListenerDemo swingListenerDemo = new ContainerListenerDemo();
swingListenerDemo.showContainerListenerDemo();
}
private void prepareGUI() {
mainFrame = new JFrame("Java SWING ContainerListener示例(yiibai.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 showContainerListenerDemo() {
headerLabel.setText("Listener in action: ContainerListener");
JPanel panel = new JPanel();
panel.setBackground(Color.blue);
panel.addContainerListener(new CustomContainerListener());
JLabel msglabel = new JLabel("欢迎您来到易百网Swing教程.", 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. ");
}
}
}
执行上面示例代码,得到以下结果: