2011-09-07 87 views
6

我有一个类whitch扩展JPanel:确定MouseListener中单击的JPanel组件。事件处理

public class ButtonPanel extends JPanel { 

    private label; 

    public ButtonPanel() { 
     label=new JLabel("waiting for click"); 
     add(label); 
    } 

    public void setButtonText() { 
     label.setText("just clicked"); 
    } 

} 

我有被添加到JFrame的那类的几个实例。我想创建一个MouseAdapter类的实例,然后将它们作为鼠标监听器添加到我的JFrame上的所有ButtonPanel组件。我想:

ButtonPanel butt1 = new ButtonPanel(); 
ButtonPanel butt2 = new ButtonPanel(); 
ButtonPanel butt3 = new ButtonPanel(); 
//... here goes code which add ButtonPanels to JFrame 

MouseAdapterMod mam = new MouseAdapterMod(); 
butt1.addMouseListener(mam); 
butt2.addMouseListener(mam); 
butt3.addMouseListener(mam); 

MouseAdapterMod类我想与另一个分开,并找到它自己的包中。它应该是这样的:

public class MouseAdapterMod extends MouseAdapter { 

    public void mouseClicked(MouseEvent e) { 
     //here goes the code of calling setButtonText method of ButtonPanel component on which the event had occurred 
    } 
} 

所以问题是,我不知道如何实现的mouseClicked方法,使其确定ButtonPanel生成事件,并调用相应于该部件setButtonText()方法。有谁知道该怎么做?

我知道我可以通过在ButtonPanel类中包含事件处理功能来实现此目的,但这对我来说不是合适的方式,因为我想保留上面描述的类结构,并且只有一个MouseAdapterMod类的实例处理所有的ButtonPanel。

+0

荣誉为您的最后一段。 –

回答

14

MouseEvent#getSource方法将返回对象已被点击其中:

public class MouseAdapterMod extends MouseAdapter { 

    // usually better off with mousePressed rather than clicked 
    public void mousePressed(MouseEvent e) { 
     ButtonPanel btnPanel = (ButtonPanel)e.getSource(); 
     btnPanel.setButtonText(); 
    } 
} 

正如注释笔记,你通常能够更好地倾听或的mousePressed的mouseReleased,而不是因为的mouseClicked为的mouseClicked工作,新闻发布必须来自同一点,如果鼠标移动的数量很少,则点击将不会注册。

我的测试程序:

import java.awt.Color; 
import java.awt.GridLayout; 
import java.awt.event.*; 

import javax.swing.*; 

public class MainForButtonPanel extends JPanel { 
    public MainForButtonPanel() { 
     setLayout(new GridLayout(4, 4)); 

     MouseAdapter myMA = new MouseAdapterMod(); 

     for (int i = 0; i < 4; i++) { 
     for (int j = 0; j < 4; j++) { 
      ButtonPanel btnPanel = new ButtonPanel(); 
      btnPanel.addMouseListener(myMA); 
      add(btnPanel); 
     } 
     } 

    } 

    private static void createAndShowUI() { 
     JFrame frame = new JFrame("MainForButtonPanel"); 
     frame.getContentPane().add(new MainForButtonPanel()); 
     frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE); 
     frame.pack(); 
     frame.setLocationRelativeTo(null); 
     frame.setVisible(true); 
    } 

    public static void main(String[] args) { 
     java.awt.EventQueue.invokeLater(new Runnable() { 
     public void run() { 
      createAndShowUI(); 
     } 
     }); 
    } 
} 

class ButtonPanel extends JPanel { 

    private static final int TIMER_DELAY = 2000; 
    private static final String JUST_CLICKED = "just clicked"; 
    private static final String WAITING_FOR_CLICK = "waiting for click"; 
    private static final Color CLICKED_COLOR = Color.pink; 
    private JLabel label; 

    public ButtonPanel() { 
     label = new JLabel(WAITING_FOR_CLICK); 
     add(label); 
    } 

    public void setButtonText() { 
     label.setText(JUST_CLICKED); 
     setBackground(CLICKED_COLOR); 

     new Timer(TIMER_DELAY, new ActionListener() { 
     public void actionPerformed(ActionEvent ae) { 
      label.setText(WAITING_FOR_CLICK); 
      setBackground(null); 
      ((Timer)ae.getSource()).stop(); 
     } 
     }).start(); 
    } 

} 

class MouseAdapterMod extends MouseAdapter { 

    // usually better off with mousePressed rather than clicked 
    public void mousePressed(MouseEvent e) { 
     ButtonPanel btnPanel = (ButtonPanel)e.getSource(); 
     btnPanel.setButtonText(); 
    } 
} 
+1

+1,'getSource()'在编写共享侦听器时再次拯救。 – camickr

+0

+1个不错的例子:-) – kleopatra

+0

优秀的例子。我比我问的还要多。但不知道'setButtonText()'方法中'Timer'实例是什么意思。对不起,在java新手;)..但无论如何,非常感谢你! – Gubert