如何实现按钮拖拽？

Question

改如何实现像在flash中button的拖拽功能？要以什么作为按钮的容器？

Answer 1

没做过，但是可以提供思路（做过关于Panel的例子）1.产生一个BUTTON2.面板注册鼠标拖拽事件3.对比现有BUTTON和鼠标位置，并进行判断。4.if(true)，则删除原来的BUTTON，把现在的BUTTON加到面板上。else则不动

Answer 2

import java.awt.FlowLayout;
import java.awt.Point;
import java.awt.event.MouseAdapter;
import java.awt.event.MouseEvent;import javax.swing.JButton;
import javax.swing.JFrame;public class DragButtonTest extends JFrame {    private JButton dragBtn;    public DragButtonTest() {
        this.initComponent();
        this.getContentPane().setLayout(new FlowLayout());
        this.getContentPane().add(this.dragBtn);
    }    private void initComponent() {
        if (this.dragBtn == null) {
            this.dragBtn = new JButton("dragBtn");
            this.dragBtn.addMouseListener(new MouseAdapter() {
                private Point oldPoint = new Point();                @Override
                public void mousePressed(MouseEvent e) {
                    this.oldPoint.x = e.getX();
                    this.oldPoint.y = e.getY();
                }                @Override
                public void mouseReleased(MouseEvent e) {
                    if (this.oldPoint.x != e.getX() || this.oldPoint.y != e.getY()) {
                        DragButtonTest.this.dragBtn.setLocation(new Point(
                            DragButtonTest.this.dragBtn.getLocation().x
                                + e.getX()
                                - this.oldPoint.y,
                            DragButtonTest.this.dragBtn.getLocation().y
                                + e.getY()
                                - this.oldPoint.y));
                        this.oldPoint.x = e.getX();
                        this.oldPoint.y = e.getY();
                        DragButtonTest.this.repaint();
                    }
                }                @Override
                public void mouseDragged(MouseEvent e) {                }
            });
        }
    }    /**
     * @param args
     */
    public static void main(String[] args) {
        DragButtonTest dbt = new DragButtonTest();
        dbt.setVisible(true);
        dbt.setSize(300, 300);
        dbt.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
    }}如果想让按钮跟着鼠标走，那么应该将逻辑放到mouseDragged中，不过这样性能会差一些

Answer 3

行，按照你的代码可以实现拖动了，可是我把mouseReleased中的内容拷到mouseDragged里面，为什么不能实现让按钮跟着鼠标走？而且好像无论把什么内容加到mouseDragged中都没有作用

Answer 4

import java.awt.FlowLayout; 
import java.awt.Point; 
import java.awt.event.MouseAdapter; 
import java.awt.event.MouseEvent; import javax.swing.JButton; 
import javax.swing.JFrame; public class DragButtonTest extends JFrame {     private JButton dragBtn;     public DragButtonTest() { 
        this.initComponent(); 
        this.getContentPane().setLayout(new FlowLayout()); 
        this.getContentPane().add(this.dragBtn); 
    }     private void initComponent() { 
        if (this.dragBtn == null) { 
            this.dragBtn = new JButton("dragBtn"); 
            
            this.dragBtn.addMouseMotionListener(new java.awt.event.MouseMotionAdapter() { 
                private Point oldPoint = new Point(); 
                
                @Override 
                public void mouseDragged(MouseEvent e) {
                 if (e.getX() - this.oldPoint.x >= 5 || e.getY() - this.oldPoint.y >= 5
                 || e.getX() - this.oldPoint.x <= -5 || e.getY() - this.oldPoint.y <= -5){ 
                 DragButtonTest.this.dragBtn.setLocation(new Point( 
                 DragButtonTest.this.dragBtn.getLocation().x 
                 + e.getX() 
                - this.oldPoint.x, 
                           DragButtonTest.this.dragBtn.getLocation().y 
                            + e.getY() 
                            - this.oldPoint.y)); 
        
                DragButtonTest.this.repaint(); 
                } 
                System.out.println("HELLO");
                } 
               }
           ); 
        } 
    }     /** 
    * @param args 
    */ 
    public static void main(String[] args) { 
        DragButtonTest dbt = new DragButtonTest(); 
        dbt.setVisible(true); 
        dbt.setSize(300, 300); 
        dbt.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE); 
    } } 
可实现连续拖拽