title: JComponent.WHEN_IN_FOCUSED_WINDOW cannot work with JCombobox
body: <p>I had screen below:
  <img src="https://i.stack.imgur.com/ovSQZ.png" alt="enter image description here"></p>
  
  <pre><code>public BillSummaryScreen() {
     ..........
     ShortcutKeyUtils.createShortcutKey(this, KeyEvent.VK_ENTER, "enterShortcut", new EnterAction());
  
  }
  
  public static void createShortcutKey(JComponent panel, int keyEventCode, String actionShortcutName, AbstractAction action){
          InputMap inputMap =  panel.getInputMap(JComponent.WHEN_IN_FOCUSED_WINDOW);
          inputMap.put(KeyStroke.getKeyStroke(keyEventCode, 0), actionShortcutName);
          ActionMap actionMap = panel.getActionMap();
          actionMap.put(actionShortcutName, action);
      }
  
  private class EnterAction extends AbstractAction{
  
          @Override
          public void actionPerformed(ActionEvent arg0) {
              System.out.println("EnterAction");
          }
  
      }
  </code></pre>
  
  <p>I want to press "ENTER" key so the search button is clicked. <strong>But when i focus into one combobox(by mouse) and i pressed ENTER, the action did not work</strong></p>