偵聽嵌套面板中的擊鍵

Question

在下面的Java文件中，我創建了一個包含面板的框架，然後嵌套第二個面板。我試圖在嵌套面板中聽按鍵。我的方法是使用輸入映射和動作映射。我發現如果我只有嵌套面板的輸入映射，事情按預期工作。但是，如果父面板也具有輸入映射，則鍵擊事件不會傳遞到嵌套面板。您可以通過註釋和取消註釋第一次調用getInputMap（）。put來觀察此行爲。有沒有人有這個解決方案？

import java.awt.BorderLayout; 
import java.awt.event.ActionEvent; 
import java.awt.event.KeyEvent; 

import javax.swing.AbstractAction; 
import javax.swing.JFrame; 
import javax.swing.JPanel; 
import javax.swing.KeyStroke; 
import javax.swing.SwingUtilities; 

public class InputMapTest extends JPanel { 

    public InputMapTest() { 
     super(new BorderLayout()); 
     JPanel panel = new JPanel(); 
     KeyStroke ks = KeyStroke.getKeyStroke(KeyEvent.VK_ENTER, 0); 
     getInputMap().put(ks, "someAction"); 
     getActionMap().put("someAction", new AbstractAction() { 
      @Override 
      public void actionPerformed(ActionEvent e) { 
       System.out.println("here1"); 
      } 
     }); 
     ks = KeyStroke.getKeyStroke(KeyEvent.VK_SPACE, 0); 
     panel.getInputMap().put(ks, "someOtherAction"); 
     panel.getActionMap().put("someOtherAction", new AbstractAction() { 
      @Override 
      public void actionPerformed(ActionEvent e) { 
       System.out.println("here2"); 
      } 
     }); 
     add(panel); 
    } 

    public static void main(String[] args) { 
     SwingUtilities.invokeLater(new Runnable() { 
      @Override 
      public void run() { 
       JFrame frame = new JFrame(); 
       frame.getContentPane().add(new InputMapTest()); 
       frame.setSize(800, 600); 
       frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE); 
       frame.setLocationRelativeTo(null); 
       frame.setVisible(true); 
      } 
     }); 
    } 

} 

Answer 1

• 看到甲骨文教程How to use KeyBindings

• 你錯過那裏將焦點設置的JPanel panel.getInputMap(JComponent.WHEN_IN_FOCUSED_WINDOW).put(...)