mousetracker.java

来自「java 课件与资料 java 课件与资料 java 课件与资料 java 课件」· Java 代码 · 共 86 行

// Fig. 13.17: MouseTracker.java
// Demonstrating mouse events.
import java.awt.*;
import java.awt.event.*;
import javax.swing.*;

public class MouseTracker extends JFrame
   implements MouseListener, MouseMotionListener {

   private JLabel statusBar;

   // set up GUI and register mouse event handlers
   public MouseTracker()
   {
      super( "Demonstrating Mouse Events" );

      statusBar = new JLabel();
      getContentPane().add( statusBar, BorderLayout.SOUTH );
    
      addMouseListener( this );        // listens for own mouse and
      addMouseMotionListener( this );  // mouse-motion events

      setSize( 275, 100 );
      setVisible( true );
   }

   // MouseListener event handlers
   // handle event when mouse released immediately after press
   public void mouseClicked( MouseEvent event )
   {
      statusBar.setText( "Clicked at [" + event.getX() +
         ", " + event.getY() + "]" );
   }

   // handle event when mouse pressed
   public void mousePressed( MouseEvent event )
   {
      statusBar.setText( "Pressed at [" + event.getX() +
         ", " + event.getY() + "]" );
   }

   // handle event when mouse released after dragging
   public void mouseReleased( MouseEvent event )
   {
      statusBar.setText( "Released at [" + event.getX() +
         ", " + event.getY() + "]" );
   }

   // handle event when mouse enters area
   public void mouseEntered( MouseEvent event )
   {
      statusBar.setText( "Mouse entered at [" + event.getX() +
         ", " + event.getY() + "]" );
      getContentPane().setBackground( Color.GREEN );
   }

   // handle event when mouse exits area
   public void mouseExited( MouseEvent event )
   {
      statusBar.setText( "Mouse outside window" );
      getContentPane().setBackground( Color.WHITE );
   }

   // MouseMotionListener event handlers
   // handle event when user drags mouse with button pressed
   public void mouseDragged( MouseEvent event )
   {
      statusBar.setText( "Dragged at [" + event.getX() + 
         ", " + event.getY() + "]" );
   }

   // handle event when user moves mouse
   public void mouseMoved( MouseEvent event )
   {
      statusBar.setText( "Moved at [" + event.getX() +
         ", " + event.getY() + "]" );
   }

   public static void main( String args[] )
   { 
      MouseTracker application = new MouseTracker();
      application.setDefaultCloseOperation( JFrame.EXIT_ON_CLOSE );
   }

} // end class MouseTracker