Question

在我的代码中，我有一个菜单项，其动作由动作地图附加（menuItem.setActionName("someString")）。

在动作地图中，作为值，我使用已实现的AbstractAction方法扩展actionPerformed的类对象。我的问题是，如何将鼠标事件（点击menuItem时发布的鼠标）的修饰符传递给actionPerformed？我必须检查在actionPerformed方法中是否使用ctrl执行操作。有关修饰符的信息在MouseEvent中，但调用堆栈显示调用了菜单项上的doClick，调用actionPerformed（通过setPressed）。在那一刻，没有传递来自MouseEvent的修饰符的信息，因此丢失了所需的信息。

谢谢！

Answer 1

尝试覆盖扩展processMouseEvent的类的JMenuItem。您可以MouseEvent方法从processMouseEvent获取修饰符。

Answer 2

这是一个代码示例。

import java.awt.event.ActionEvent;
import java.util.HashMap;
import java.util.Map;
import javax.swing.AbstractAction;
import javax.swing.JOptionPane;

/*
 * To change this license header, choose License Headers in Project Properties.
 * To change this template file, choose Tools | Templates
 * and open the template in the editor.
 */
public class SSCE extends javax.swing.JFrame {
   private static final String ACTION_NAME = "action";
   private Map<String, MyAction> actionMap = new HashMap<>();
   /**
    * Creates new form SSCE
    */
   public SSCE() {
      initComponents();
      actionMap.put(ACTION_NAME, new MyAction(ACTION_NAME));
      configAction();
   }

   private void configAction(){
      jMenuItem1.setAction(actionMap.get(ACTION_NAME));
   }

   /**
    * This method is called from within the constructor to
    * initialize the form.
    * WARNING: Do NOT modify this code. The content of this method is
    * always regenerated by the Form Editor.
    */
   @SuppressWarnings("unchecked")
   // <editor-fold defaultstate="collapsed" desc="Generated Code">                          
   private void initComponents() {

      jMenuBar1 = new javax.swing.JMenuBar();
      jMenu1 = new javax.swing.JMenu();
      jMenuItem1 = new javax.swing.JMenuItem();

      setDefaultCloseOperation(javax.swing.WindowConstants.EXIT_ON_CLOSE);

      jMenu1.setText("jMenu1");
      jMenu1.add(jMenuItem1);

      jMenuBar1.add(jMenu1);

      setJMenuBar(jMenuBar1);

      javax.swing.GroupLayout layout = new javax.swing.GroupLayout(getContentPane());
      getContentPane().setLayout(layout);
      layout.setHorizontalGroup(
         layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
         .addGap(0, 400, Short.MAX_VALUE)
      );
      layout.setVerticalGroup(
         layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
         .addGap(0, 279, Short.MAX_VALUE)
      );

      pack();
   }// </editor-fold>                        

   /**
    * @param args the command line arguments
    */
   public static void main(String args[]) {
      /*
       * Set the Nimbus look and feel
       */
      //<editor-fold defaultstate="collapsed" desc=" Look and feel setting code (optional) ">
        /*
       * If Nimbus (introduced in Java SE 6) is not available, stay with the default look and feel.
       * For details see http://download.oracle.com/javase/tutorial/uiswing/lookandfeel/plaf.html
       */
      try {
         for (javax.swing.UIManager.LookAndFeelInfo info : javax.swing.UIManager.getInstalledLookAndFeels()) {
            if ("Nimbus".equals(info.getName())) {
               javax.swing.UIManager.setLookAndFeel(info.getClassName());
               break;
            }
         }
      } catch (ClassNotFoundException ex) {
         java.util.logging.Logger.getLogger(SSCE.class.getName()).log(java.util.logging.Level.SEVERE, null, ex);
      } catch (InstantiationException ex) {
         java.util.logging.Logger.getLogger(SSCE.class.getName()).log(java.util.logging.Level.SEVERE, null, ex);
      } catch (IllegalAccessException ex) {
         java.util.logging.Logger.getLogger(SSCE.class.getName()).log(java.util.logging.Level.SEVERE, null, ex);
      } catch (javax.swing.UnsupportedLookAndFeelException ex) {
         java.util.logging.Logger.getLogger(SSCE.class.getName()).log(java.util.logging.Level.SEVERE, null, ex);
      }
      //</editor-fold>

      /*
       * Create and display the form
       */
      java.awt.EventQueue.invokeLater(new Runnable() {
         public void run() {
            new SSCE().setVisible(true);
         }
      });
   }

   // Variables declaration - do not modify                     
   private javax.swing.JMenu jMenu1;
   private javax.swing.JMenuBar jMenuBar1;
   private javax.swing.JMenuItem jMenuItem1;
   // End of variables declaration                   

   private static class MyAction extends AbstractAction {

      public MyAction(String name) {
         super(name);
      }

      @Override
      public void actionPerformed(ActionEvent e) {
         if (ActionEvent.CTRL_MASK == (ActionEvent.CTRL_MASK & e.getModifiers())) {
            JOptionPane.showMessageDialog(null, "Run with ctrl mode");
         } else {
            JOptionPane.showMessageDialog(null, "Run with normal mode");
         }
      }

   }
}

但是，我担心我错了。修改器通过（不知何故，但我不知道如何），但不是在调试模式下。我在NetBeans中测试了SSCE，我认为在调试中有一些时间依赖性使得修饰符不会被传递（你可以用上面的代码检查它。只需在actionPerformed方法的第一行设置断点）。它也适用于我的应用程序。所以我认为问题可以结束。

Ctrl掩码从鼠标事件传递到执行的操作

2 个答案: