上机题目（初级）- 鼠标控制小球（Java）

本节实现小球跟随鼠标移动的功能，这里要实现鼠标移动监听，代码如下：

import java.awt.Color;
import java.awt.Frame;
import java.awt.Graphics;
import java.awt.Panel;
import java.awt.event.MouseEvent;
import java.awt.event.MouseMotionListener;

public class KeyListenerDemo {

	public static void main(String[] args) {
		Frame frame = new Frame();
		frame.setSize(800, 800);
		frame.setBackground(Color.BLACK);
		MyPanel myPanel = new MyPanel();
		frame.add(myPanel);
		frame.addMouseMotionListener(myPanel);
		myPanel.addMouseMotionListener(myPanel);

		frame.show();

	}
}

class MyPanel extends Panel implements MouseMotionListener {
	int x = 150;
	int y = 150;

	@Override
	public void paint(Graphics g) {
		g.setColor(Color.WHITE);
		g.fillOval(x, y, 20, 20);
	}

	@Override
	public void mouseDragged(MouseEvent e) {

	}

	@Override
	public void mouseMoved(MouseEvent e) {
		x=e.getX();
		y=e.getY();
		repaint();

	}

}

代码运行实例如下：