JFrame拖动&&去边框

setUndecorated(true);   JFrame   È¥±ß¿ò


A   sample:   
    
  import   java.awt.*;   
  import   javax.swing.*;   
  import   java.awt.event.*;   
    
  public   class   DragFrame   extends   JFrame{   
  private   boolean   startDrag   =   false;   
  private   Point   p   =   null;   
  public   static   void   main(String[]   args){   
  DragFrame   df   =   new   DragFrame();   
  df.setSize(400,   400);   
  df.setVisible(true);   
  }   
  public   DragFrame(){   
  addMouseListener(new   MouseAdapter(){   
  public   void   mousePressed(MouseEvent   e){   
  startDrag   =   true;   
  p   =   e.getPoint();   
  }   
  public   void   mouseReleased(MouseEvent   e){   
  startDrag   =   false;   
  }   
  });   
  addMouseMotionListener(new   MouseMotionAdapter(){   
  public   void   mouseDragged(MouseEvent   e){   
  Point   p1   =   e.getPoint();