2021-09-22 GUI(键盘事件)

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

public class MouseAndKeyEvent {

    // 定义该图形中所需的组件的引用
    private Frame f;
    private Button btn;
    private TextField textField;// 文本框

    public MouseAndKeyEvent() {
        init();
    }

    private void init() {
        f = new Frame("my frame");
        f.setBounds(300, 100, 500, 400);
        f.setLayout(new FlowLayout());
        btn = new Button("my Button");
        textField = new TextField(20);
        f.add(textField);
        f.add(btn);
        myEvent();
        f.setVisible(true);
    }

    private void myEvent() {
        f.addWindowListener(new WindowAdapter() {

            @Override
            public void windowClosing(WindowEvent e) {
                System.exit(0);
            }

        });

        // 文本框监听
        textField.addKeyListener(new KeyAdapter() {

            @Override
            public void keyPressed(KeyEvent e) {
                int code = e.getKeyCode();
                if (!(code >= KeyEvent.VK_0 && code <= KeyEvent.VK_9)) {
//                  System.out.println(code + "是非法的");
                    e.consume();
                }
            }

        });
        // 给btn添加一个键盘监听
        btn.addKeyListener(new KeyAdapter() {

            @Override
            public void keyPressed(KeyEvent e) {
                // if (e.getKeyCode() == KeyEvent.VK_ENTER) {
                // System.exit(0);
                // }
                // 组合键ctrl+Enter
                if (e.isControlDown() && e.getKeyCode() == KeyEvent.VK_ENTER) {
                    // System.exit(0);
                    System.out.println("ctrl + enter is run");
                }
                // System.out.println(e.getKeyChar() + "..." + e.getKeyCode());
                // System.out.println(KeyEvent.getKeyText(e.getKeyCode()) +
                // "..." + e.getKeyCode());
            }

        });

        btn.addActionListener(e -> System.out.println("action ok"));

        btn.addMouseListener(new MouseAdapter() {

            private int count = 0;
            private int clickCount = 0;

            @Override
            public void mouseEntered(MouseEvent e) {
                System.out.println("鼠标进入到该组件：" + count++);
            }

            @Override
            public void mouseClicked(MouseEvent e) {
                if (e.getClickCount() == 2)
                    System.out.println("双击动作：" + clickCount++);
            }

        });
    }

    public static void main(String[] args) {
        new MouseAndKeyEvent();
    }

}