学习笔记二十六：事件处理（二）

在这个并非尽善尽美的世界上，勤奋会得到报偿，而游手好闲则要受到惩罚。——毛姆

本讲内容：MouseEvent 、MouseMotionListener

一、MouseEvent   让鼠标能知道鼠标按下的消息、知道点击的位置等五个方法。

MouseMotionListener鼠标拖动坐标、鼠标移动坐标二个方法。

public class Text extends JFrame {
	MyPanel mb=null;

	public static void main(String[] args) {
		Text t=new Text();//每定义一个 t 都会产生一个对应的this
	}

	public Text() {
		mb=new MyPanel();
		this.addMouseListener(mb);//添加监听
		this.addMouseMotionListener(mb);
		this.add(mb);

		//设置窗体属性
		this.setTitle("技术大牛—小劲");
		this.setLocation(300, 300);
		this.setSize(400,400);
		this.setVisible(true);
		this.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
	}
}

class MyPanel extends JPanel implements MouseListener,MouseMotionListener{
	public void paint(Graphics g) {
		super.paint(g);
	}

	//MouseListener  接口方法
	//鼠标被点击(鼠标按下然后松开后执行)
	public void mouseClicked(MouseEvent e) {
		System.out.println("鼠标点击了 x="+e.getX()+"y="+e.getY());
	}

	//鼠标移动到MyPanel
	public void mouseEntered(MouseEvent e) {
		System.out.println("鼠标移动到MyPanel");
	}

	//鼠标离开MyPanel
	public void mouseExited(MouseEvent e) {
		System.out.println("鼠标离开MyPanel");
	}

	//鼠标按下
	public void mousePressed(MouseEvent e) {
		System.out.println("鼠标按下");
	}

	//鼠标松开
	public void mouseReleased(MouseEvent e) {
		System.out.println("鼠标松开");
	}

	//MouseMotionListener  接口方法
	//鼠标拖动
	public void mouseDragged(MouseEvent e) {
		System.out.println("鼠标拖拽的当前坐标  x="+e.getX()+"y="+e.getY());
	}

	//鼠标移动
	public void mouseMoved(MouseEvent e) {
		System.out.println("鼠标当前坐标  x="+e.getX()+"y="+e.getY());
	}
}

二、KeyListener 键盘事件有三个方法。WindowListener 窗口事件有七个方法。

public class Text extends JFrame {
	MyPanel mb=null;

	public static void main(String[] args) {
		Text t=new Text();
	}

	public Text() {
		mb=new MyPanel();
		this.addKeyListener(mb);
		this.addWindowListener(mb);
		this.add(mb);

		//设置窗体属性
		this.setTitle("技术大牛—小劲");
		this.setLocation(300, 300);
		this.setSize(400,400);
		this.setVisible(true);
		this.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
	}
}

class MyPanel extends JPanel implements KeyListener,WindowListener{
	public void paint(Graphics g) {
		super.paint(g);
	}

	//键被按下
	public void keyPressed(KeyEvent e) {
		System.out.println(e.getKeyChar()+"键被按下了");//e.getKeyCode()是ASCII码
	}

	//键被释放
	public void keyReleased(KeyEvent e) {

	}

	//键的一个值被打印输出（上下左右键等不会执行，因为没打印出）
	public void keyTyped(KeyEvent e) {

	}

	//窗口激活了(窗口还原后即激活)
	public void windowActivated(WindowEvent e) {
		System.out.println("窗口激活了");
	}

	//窗口关闭
	public void windowClosed(WindowEvent e) {//很少用到
		System.out.println("窗口关闭");
	}

	//窗口正在关闭
	public void windowClosing(WindowEvent e) {
		System.out.println("窗口正在关闭");
	}

	//窗口失去激活（窗口最小化）
	public void windowDeactivated(WindowEvent e) {
		System.out.println("窗口失去激活");
	}

	//窗口还原
	public void windowDeiconified(WindowEvent e) {
		System.out.println("窗口还原");
	}

	//窗口最小化
	public void windowIconified(WindowEvent e) {
		System.out.println("窗口最小化");
	}

	 //窗口打开
	public void windowOpened(WindowEvent e) {
		System.out.println("窗口打开");
	}
}

本讲就到这里，Take your time and enjoy it