Java新增事件監聽的四種方法程式碼例項
阿新 • • 發佈:2019-01-06
1.Java事件監聽處理——自身類實現ActionListener介面,作為事件監聽器
class EventListener1 extends JFrame implements ActionListener { private JButton btBlue, btDialog; public EventListener1() { setTitle("Java GUI 事件監聽處理"); setBounds(100, 100, 500, 350); setLayout(new FlowLayout()); btBlue = new JButton("藍色"); btDialog = new JButton("彈窗"); // 將按鈕新增事件監聽器 btBlue.addActionListener(this); btDialog.addActionListener(this); add(btBlue); add(btDialog); setVisible(true); setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE); } // ***************************事件處理*************************** @Override public void actionPerformed(ActionEvent e) { if (e.getSource() == btBlue) { Container c = getContentPane(); c.setBackground(Color.BLUE); } else if (e.getSource() == btDialog) { JDialog dialog = new JDialog(); dialog.setBounds(300, 200, 400, 300); dialog.setVisible(true); } } }
2.內部類
class EventListener3 extends JFrame { private JButton btBlue, btDialog; // 構造方法 public EventListener3() { setTitle("Java GUI 事件監聽處理"); setBounds(100, 100, 500, 350); setLayout(new FlowLayout()); btBlue = new JButton("藍色"); btDialog = new JButton("彈窗"); // 新增事件監聽器物件(面向物件思想) btBlue.addActionListener(new ColorEventListener()); btDialog.addActionListener(new DialogEventListener()); add(btBlue); add(btDialog); setVisible(true); setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE); } // 內部類ColorEventListener,實現ActionListener介面 class ColorEventListener implements ActionListener { @Override public void actionPerformed(ActionEvent e) { Container c = getContentPane(); c.setBackground(Color.BLUE); } } // 內部類DialogEventListener,實現ActionListener介面 class DialogEventListener implements ActionListener { @Override public void actionPerformed(ActionEvent e) { JDialog dialog = new JDialog(); dialog.setBounds(300, 200, 400, 300); dialog.setVisible(true); } } }
3.匿名內部類
class EventListener2 extends JFrame { private JButton btBlue, btDialog; public EventListener2() { setTitle("Java GUI 事件監聽處理"); setBounds(100, 100, 500, 350); setLayout(new FlowLayout()); btBlue = new JButton("藍色"); btDialog = new JButton("彈窗"); // 新增事件監聽器(此處即為匿名類) btBlue.addActionListener(new ActionListener() { // 事件處理 @Override public void actionPerformed(ActionEvent e) { Container c = getContentPane(); c.setBackground(Color.BLUE); } }); // 並新增事件監聽器 btDialog.addActionListener(new ActionListener() { @Override public void actionPerformed(ActionEvent e) { JDialog dialog = new JDialog(); dialog.setBounds(300, 200, 400, 300); dialog.setVisible(true); } }); add(btBlue); add(btDialog); setVisible(true); setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE); } }
4.外部類
class EventListener4 extends JFrame { private JButton btBlue, btDialog; public EventListener4() { setTitle("Java GUI 事件監聽處理"); setBounds(100, 100, 500, 350); setLayout(new FlowLayout()); btBlue = new JButton("藍色"); btDialog = new JButton("彈窗"); // 將按鈕新增事件監聽器 btBlue.addActionListener(new ColorEventListener(this)); btDialog.addActionListener(new DialogEventListener()); add(btBlue); add(btDialog); setVisible(true); setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE); } } // 外部類ColorEventListener,實現ActionListener介面 class ColorEventListener implements ActionListener { private EventListener4 el; ColorEventListener(EventListener4 el) { this.el = el; } @Override public void actionPerformed(ActionEvent e) { Container c = el.getContentPane(); c.setBackground(Color.BLUE); } } // 外部類DialogEventListener,實現ActionListener介面 class DialogEventListener implements ActionListener { @Override public void actionPerformed(ActionEvent e) { JDialog dialog = new JDialog(); dialog.setBounds(300, 200, 400, 300); dialog.setVisible(true); } } public class ActionListenerTest { public static void main(String args[]) { new EventListener4(); } }