如何添加Keylistener到Vaadin的ListSelect？

Question

我有，我想，如果使用的關鍵DEL刪除項vaadin ListSelect組件。

所有我發現是在ShortcutListener但如果我添加下面的聽衆中，DEL關鍵並不在我的應用程序的其餘部分工作（如刪除在TextField文本）：

listSelect.addShortcutListener(new ShortcutListener("", KeyCode.DELETE, null) { 
     private static final long serialVersionUID = 4703134138899283799L; 

     @Override 
     public void handleAction(Object sender, Object target) { 
      // handle delete 
     } 
    }); 

我應該如何實現DEL鍵的聽衆？

編輯：試圖用包裝Panel在意見提出，但它仍然無法正常工作。在這裏我當前的代碼：

listSelect = new ListSelect(null); 
listSelect.setWidth(100, Unit.PERCENTAGE); 
listSelect.setHeight(82, Unit.PIXELS); 
listSelect.setMultiSelect(true); 
listSelect.setNullSelectionAllowed(false); 

listSelect.setDescription("Löschen mit der DEL Taste"); 
listSelect.addShortcutListener(new ShortcutListener("", KeyCode.DELETE, null) { 
    private static final long serialVersionUID = 4703134138899283799L; 

    @Override 
    public void handleAction(Object sender, Object target) { 
     // handle delete 
    } 
}); 
Panel wrapperPanel = new Panel(listSelect); 
form.addComponent(wrapperPanel); 

的form是GridLayout的form父是Panel。該面板是TabSheet的一部分。我正在使用Vaadin版本7.7.1。

Answer 1

望着sources (currently line 110)，似乎動作委託給包含窗口...

/** 
* Keeps track of the Actions added to this component; the actual 
* handling/notifying is delegated, usually to the containing window. 
*/ 
private ConnectorActionManager actionManager; 

...或父容器至少，因爲基於這個問題Select-all shortcut (Ctrl-A) in Vaadin Table?你可以解決這個問題。如果您纏繞列表中選擇一個面板和短切監聽器添加到面板相反，它按預期工作：

public class MyListSelectComponent extends VerticalLayout { 

    public MyListSelectComponent() { 
     ListSelect list = new ListSelect("Press DEL to remove items"); 
     TextField input = new TextField("Focus this input and press DEL to delete some text"); 
     input.setValue("This is some very long text, or not..."); 

     for (int i = 0; i < 10; i++) { 
      list.addItem(i); 
     } 

     Panel panel = new Panel(list); 
     panel.addShortcutListener(new ShortcutListener("", ShortcutAction.KeyCode.DELETE, null) { 
      @Override 
      public void handleAction(Object sender, Object target) { 
       if (list.getValue() != null) { 
        list.removeItem(list.getValue()); 
       } 
      } 
     }); 

     addComponent(panel); 
     addComponent(input); 
    } 
} 

實際輸出：