移动组件练习

import java.awt.*;
import java.awt.event.*;
import javax.swing.*; 
import javax.swing.event.*;
public class moveText{
    Label myText;
    Frame mT;
    Point point = new Point(0, 0);
    public moveText(){
        myText=new Label("move me please!");
        mT = new Frame("moveTEXT");
        myText.setBackground(Color.yellow);
 
        mT.addWindowListener(new myWindowListener());
        mT.setLayout(new FlowLayout(FlowLayout.CENTER, 10, 10));
        mT.setSize(600, 600);
        mT.setLocation(100, 100);
        myText.addMouseMotionListener(new myMouseListener1());
        myText.addMouseListener(new myMouseListener2());
        myText.setSize(20, 5);
        mT.add(myText);
        
        mT.setVisible(true);
    }
    class myMouseListener1 extends MouseMotionAdapter {
          
         /* 
          当鼠标拖动时触发该事件。 记录下鼠标按下(开始拖动)的位置。 
         */  
        public void mouseDragged(MouseEvent e) {  
            // 转换坐标系统，将新的坐标（鼠标相对于组件的坐标）转换成该相对与其组件的父亲组件的坐标
            Point newPoint = SwingUtilities.convertPoint(myText, e  
                    .getPoint(), myText.getParent());  
            // 设置标签的新位置  
            
            myText.setLocation(myText.getX()  
                    + (newPoint.x - point.x), myText.getY()  
                    + (newPoint.y - point.y));
            
            //这时开始写的方法，明显和上面的方法差别很大
            //myText.setLocation(newPoint);
            
            // 更改坐标源点  
            point = newPoint;  
        }  
    }
    class myMouseListener2 extends MouseAdapter{
        /*
           当鼠标按下时触发该事件。 记录下鼠标按下(开始拖动)的位置。 
         */  
        public void mousePressed(MouseEvent e) {  
            // 得到当前坐标点  
            point = SwingUtilities.convertPoint(myText, e.getPoint(),  
                    myText.getParent());  
       }
    }
    public static void main(String args[]){
        moveText mT=new moveText();
        
    }
}

class myWindowListener extends WindowAdapter{
    public void windowClosing(WindowEvent e){//Frame的关闭方法
       System.exit(0);
    }
}