Java如何使用鼠标拖动来调整无边框窗口的大小？

Question

我有一个没有装饰的jFrame，只有gui是由图形GD绘制的。我希望用户调整这个窗口的大小，但不可能无界限地这样做。所以我让一个鼠标监听器在从特殊位置拖动时调整大小。它工作一点点，但不会延伸很远，直到它停止。有没有更简单的方法？还有其他的选择吗？有没有人用纯GD做过这个？

this.addMouseListener(new MouseAdapter() 
{ 
public void mousePressed(MouseEvent e) 
{ 
    posX=e.getX(); 
    posY=e.getY(); 

}  

}}); 

this.addMouseMotionListener(new MouseAdapter() 
{ 
public void mouseDragged(MouseEvent evt) 
{ 
if (posX >= getWidth()-25 && posY >=getHeight()-45){ 
int nlx= evt.getXOnScreen()-(location().x-12); 
int nly= evt.getYOnScreen()-(location().y-32); 

     setSize(nlx,nly); 
setBackground(new Color(0, 0, 0, 0)); 
invalidate(); 
    }else{ 
    setLocation (evt.getXOnScreen()-posX,evt.getYOnScreen()-posY); 

    } 

} 
}); 
} 

Answer 1

我做了类似的事情有一个JFrame，我周围有加在我的JFrame的外4个很薄按钮，以及所使用的的mousePressed和的mouseDragged监听器的按钮来控制的JFrame调整大小，它的工作非常顺利。

的的mousePressed听众让我们得到了首发的位置，这样我可以计算出距离该帧拖动/调整

如果你想节省资源，你应该调整所有子组件上松开鼠标而不是当时它被拖到

编辑：调整在X轴框架的实施例。

public class NewJFrame extends javax.swing.JFrame 
{ 
    //demo locations 
    int X1 = 0; 
    int X2 = 0; 

    public NewJFrame() 
    { 
    initComponents(); 
    } 

    @SuppressWarnings("unchecked") 
    private void initComponents() { 

     ResizeEast = new javax.swing.JButton(); 
     jButton1 = new javax.swing.JButton(); 

     setDefaultCloseOperation(javax.swing.WindowConstants.EXIT_ON_CLOSE); 
     setUndecorated(true); 

     ResizeEast.addMouseListener(new java.awt.event.MouseAdapter() { 
      public void mousePressed(java.awt.event.MouseEvent evt) { 
       ResizeEastMousePressed(evt); 
      } 
      public void mouseReleased(java.awt.event.MouseEvent evt) { 
       ResizeEastMouseReleased(evt); 
      } 
     }); 
     ResizeEast.addMouseMotionListener(new java.awt.event.MouseMotionAdapter() { 
      public void mouseDragged(java.awt.event.MouseEvent evt) { 
       ResizeEastMouseDragged(evt); 
      } 
     }); 

     jButton1.setText("Close"); 
     jButton1.addActionListener(new java.awt.event.ActionListener() { 
      public void actionPerformed(java.awt.event.ActionEvent evt) { 
       jButton1ActionPerformed(evt); 
      } 
     }); 

     javax.swing.GroupLayout layout = new javax.swing.GroupLayout(getContentPane()); 
     getContentPane().setLayout(layout); 
     layout.setHorizontalGroup(
      layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING) 
      .addGroup(layout.createSequentialGroup() 
       .addContainerGap() 
       .addComponent(jButton1) 
       .addPreferredGap(javax.swing.LayoutStyle.ComponentPlacement.RELATED, 320, Short.MAX_VALUE) 
       .addComponent(ResizeEast, javax.swing.GroupLayout.PREFERRED_SIZE, 11, javax.swing.GroupLayout.PREFERRED_SIZE)) 
     ); 
     layout.setVerticalGroup(
      layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING) 
      .addGroup(layout.createSequentialGroup() 
       .addContainerGap() 
       .addComponent(jButton1) 
       .addContainerGap(266, Short.MAX_VALUE)) 
      .addComponent(ResizeEast, javax.swing.GroupLayout.DEFAULT_SIZE, 300, Short.MAX_VALUE) 
     ); 

     pack(); 
    } 

    private void ResizeEastMousePressed(java.awt.event.MouseEvent evt) 
    { 
    //set mosuepressed location to X1 and Y1 
    X1 = evt.getX(); 
    } 

    private void ResizeEastMouseReleased(java.awt.event.MouseEvent evt) 
    { 
    //update the location and size of all child components 
    } 

    private void ResizeEastMouseDragged(java.awt.event.MouseEvent evt) 
    { 
    //resize jframe on the fly 
    X2 = evt.getX(); 
    //set minimum size to 100 wide 
    if ((getWidth() - (X1 - X2)) < 100) 
    { 
     X2 = X1; 
    } 

    //resize east side only 
    this.setSize(getWidth() - (X1 - X2), getHeight()); 
    } 

    private void jButton1ActionPerformed(java.awt.event.ActionEvent evt) 
    { 
    System.exit(0); 
    } 

    public static void main(String args[]) 
    { 
    java.awt.EventQueue.invokeLater(new Runnable() 
    { 
     public void run() 
     { 
     new NewJFrame().setVisible(true); 
     } 
    }); 
    } 
    // Variables 
    private javax.swing.JButton ResizeEast; 
    private javax.swing.JButton jButton1; 
} 

对于从边角调整大小创建调整X和Y，像这样的小角落里的按钮：YourFrame.setSize(getWidth() - (X1 - X2), getHeight() - (Y1 - Y2));

Answer 2

这是一个完整的鼠标适配器我现在使用很长一段时间：

import javax.swing.*; 
import java.awt.*; 
import java.awt.event.MouseAdapter; 
import java.awt.event.MouseEvent; 

/** 
* @see http://stackoverflow.com/a/12456113/909085 
*/ 

public class WindowResizeAdapter extends MouseAdapter implements SwingConstants 
{ 
    private boolean resizing = false; 
    private int prevX = -1; 
    private int prevY = -1; 

    private int resizeSide = 0; 

    public static void install (Component component, int resizeSide) 
    { 
     WindowResizeAdapter wra = new WindowResizeAdapter (resizeSide); 
     component.addMouseListener (wra); 
     component.addMouseMotionListener (wra); 
    } 

    public WindowResizeAdapter (int resizeSide) 
    { 
     super(); 
     this.resizeSide = resizeSide; 
    } 

    public void mousePressed (MouseEvent e) 
    { 
     if (SwingUtilities.isLeftMouseButton (e)) 
     { 
      resizing = true; 
     } 
     prevX = e.getXOnScreen(); 
     prevY = e.getYOnScreen(); 
    } 

    public void mouseDragged (MouseEvent e) 
    { 
     if (prevX != -1 && prevY != -1 && resizing) 
     { 
      Window w = SwingUtilities.getWindowAncestor (e.getComponent()); 
      Rectangle rect = w.getBounds(); 

      Dimension dim; 
      boolean undecorated; 
      if (w instanceof JDialog) 
      { 
       dim = ((JDialog) w).getContentPane().getPreferredSize(); 
       undecorated = ((JDialog) w).isUndecorated(); 
      } 
      else if (w instanceof JFrame) 
      { 
       dim = ((JFrame) w).getContentPane().getPreferredSize(); 
       undecorated = ((JFrame) w).isUndecorated(); 
      } 
      else 
      { 
       dim = w.getPreferredSize(); 
       undecorated = true; 
      } 

      // Checking for minimal width and height 
      int xInc = e.getXOnScreen() - prevX; 
      int yInc = e.getYOnScreen() - prevY; 
      if (undecorated) 
      { 
       if (resizeSide == SwingConstants.NORTH_WEST || resizeSide == SwingConstants.WEST || 
         resizeSide == SwingConstants.SOUTH_WEST) 
       { 
        if (rect.width - xInc < dim.width) 
        { 
         xInc = 0; 
        } 
       } 
       else if (resizeSide == SwingConstants.NORTH_EAST || 
         resizeSide == SwingConstants.EAST || 
         resizeSide == SwingConstants.SOUTH_EAST) 
       { 
        if (rect.width + xInc < dim.width) 
        { 
         xInc = 0; 
        } 
       } 
       if (resizeSide == SwingConstants.NORTH_WEST || 
         resizeSide == SwingConstants.NORTH || 
         resizeSide == SwingConstants.NORTH_EAST) 
       { 
        if (rect.height - yInc < dim.height) 
        { 
         yInc = 0; 
        } 
       } 
       else if (resizeSide == SwingConstants.SOUTH_WEST || 
         resizeSide == SwingConstants.SOUTH || 
         resizeSide == SwingConstants.SOUTH_EAST) 
       { 
        if (rect.height + yInc < dim.height) 
        { 
         yInc = 0; 
        } 
       } 
      } 

      // Resizing window if any changes are done 
      if (xInc != 0 || yInc != 0) 
      { 
       if (resizeSide == SwingConstants.NORTH_WEST) 
       { 
        w.setBounds (rect.x + xInc, rect.y + yInc, rect.width - xInc, 
          rect.height - yInc); 
       } 
       else if (resizeSide == SwingConstants.NORTH) 
       { 
        w.setBounds (rect.x, rect.y + yInc, rect.width, rect.height - yInc); 
       } 
       else if (resizeSide == SwingConstants.NORTH_EAST) 
       { 
        w.setBounds (rect.x, rect.y + yInc, rect.width + xInc, rect.height - yInc); 
       } 
       else if (resizeSide == SwingConstants.WEST) 
       { 
        w.setBounds (rect.x + xInc, rect.y, rect.width - xInc, rect.height); 
       } 
       else if (resizeSide == SwingConstants.EAST) 
       { 
        w.setBounds (rect.x, rect.y, rect.width + xInc, rect.height); 
       } 
       else if (resizeSide == SwingConstants.SOUTH_WEST) 
       { 
        w.setBounds (rect.x + xInc, rect.y, rect.width - xInc, rect.height + yInc); 
       } 
       else if (resizeSide == SwingConstants.SOUTH) 
       { 
        w.setBounds (rect.x, rect.y, rect.width, rect.height + yInc); 
       } 
       else if (resizeSide == SwingConstants.SOUTH_EAST) 
       { 
        w.setBounds (rect.x, rect.y, rect.width + xInc, rect.height + yInc); 
       } 
       prevX = e.getXOnScreen(); 
       prevY = e.getYOnScreen(); 
      } 
     } 
    } 

    public void mouseReleased (MouseEvent e) 
    { 
     resizing = false; 
    } 
} 

只需使用其“安装”方法将窗口调整大小行为添加到任何组件。 resizeSide变量用于定义窗口的哪一侧应调整大小（例如，SwingConstants.SOUTH_EAST将强制组件调整窗口的右下角）。

编辑：您可能还想修改特定情况下的代码，以便仅从组件上的某个特定区域开始拖动（调整大小）。只需修改mousePressed方法即可。也