问答题

本题的功能是跟踪鼠标在窗口的操作,以及在窗口的坐标,包括移进、移出、移动、单击、释放和拖曳,并将这些信息显示在窗口的文字标签上。
import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
public class java3 extends JFrame implements MouseL-
istener MouseMotionListener
{
private JLabel statusBar;
public java3()
{
super("java3");
statllsBar=new TLabel();
getContentPane.add(statusBar,BorderLayout.
SOUTH);
addMouseListener(this);
addMouseMotionListener(this);
setSize(275,100);
show();
}
public void mouseClicked(MouseEvent e)
{
statusBar.setText("Clicked at["+e.getX()+
","+e.getY()+"]");
}
public void mousePressed(MouseEvent e)

statusBar.setText("Pressed at["+e.getX()+
","+e.getY()+"]");
}
public void mouseReleased(MouseEvent e)
{ statusBar.setText("Released at["+e.getX()
+","+e.getY()+"]");
}
public void mouseln(MouseEvent e)
{
statusBar.setText("Mouse in window");
public void mouseExited(MouseEvent e)
{
statusBar.setText("Mouse outside window");
}
public void mouseDragged(MouseEvent e)
{
statusBar.setText("Dragged at["+e.getX()
+","+e.getY()+"]");
}
public void mouseMoved(MouseEvent e)
{
statusBar.setText("Moved at["+e.getX()+
","+e.getY()+"]");
}
public static void main(String args[])
{
java3 app=new java3();
app.addWindowListener(new WindowAdapter()
{
public void windowClosing(WindowEvent e)
{
System.exit(0);
}
};

【参考答案】

第1处:extends JFrame implements MouseListener,MouseMotionListe......

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