使JList的行爲點擊與按Ctrl +單擊相同的方式？

Question

我正在尋找一種方法來使JList始終切換所選項目的選擇而不取消其他人的選擇，如同ctrl點擊的作品。

ListSelectionModel似乎是正確的路要走，但我不明白什麼必須在那裏配置。

如何使一個JList上點擊以同樣的方式表現爲對CTRL點擊？

Answer 1

你必須讓自己的ListSelectionModel。嘗試一下。

list.setSelectionModel(new DefaultListSelectionModel() 
{ 
    @Override 
    public void setSelectionInterval(int index0, int index1) 
    { 
     if(list.isSelectedIndex(index0)) 
     { 
      list.removeSelectionInterval(index0, index1); 
     } 
     else 
     { 
      list.addSelectionInterval(index0, index1); 
     } 
    } 
}); 

Answer 2

也許這個代碼可以做到這一點正確

import java.awt.Component; 
import java.awt.event.InputEvent; 
import java.awt.event.MouseEvent; 
import javax.swing.*; 

public class Ctrl_Down_JList { 

    private static void createAndShowUI() { 
     String[] items = {"Sun", "Mon", "Tues", "Wed", "Thurs", "Fri", "Sat"}; 
     JList myJList = new JList(items) { 

      private static final long serialVersionUID = 1L; 

      @Override 
      protected void processMouseEvent(MouseEvent e) { 
       int modifiers = e.getModifiers() | InputEvent.CTRL_MASK; 
       // change the modifiers to believe that control key is down 
       int modifiersEx = e.getModifiersEx() | InputEvent.CTRL_MASK; 
       // can I use this anywhere? I don't see how to change the modifiersEx of the MouseEvent 
       MouseEvent myME = new MouseEvent((Component) e.getSource(), e.getID(), e.getWhen(), modifiers, e.getX(), 
         e.getY(), e.getXOnScreen(), e.getYOnScreen(), e.getClickCount(), e.isPopupTrigger(), e.getButton()); 
       super.processMouseEvent(myME); 
      } 
     }; 
     JFrame frame = new JFrame("Ctrl_Down_JList"); 
     frame.add(new JScrollPane(myJList)); 
     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() { 

      @Override 
      public void run() { 
       createAndShowUI(); 
      } 
     }); 
    } 

Answer 3

您可以使用以下ListSelectionModel：

list.setSelectionModel(new DefaultListSelectionModel(){ 
    @Override 
    public void setSelectionInterval(int start, int end) { 
     if (start != end) { 
      super.setSelectionInterval(start, end); 
     } else if (isSelectedIndex(start)) { 
      removeSelectionInterval(start, end); 
     } else { 
      addSelectionInterval(start, end); 
     } 
    } 
});