GwtChosen與GWT LayoutPanel和RootLayoutPanel搭配不好

我正在使用GwtChosen 1.1.0和GwtQuery 1.3.3。它似乎只適用於RootPanel小部件，而不適用於RootLayoutPanel小部件。GwtChosen與GWT LayoutPanel和RootLayoutPanel搭配不好

對於GwtChosen而言，RootLayoutPanel是一個已知的限制嗎？

示例代碼和截圖如下。注意RootLayoutPanel示例隱藏堆棧中GWTChosen小部件的下拉列表，從而使其不可用。

public void onModuleLoad() { 
    if (!ChosenListBox.isSupported()) 
    { 
     $("#browserWarning").show(); 
    } 

    ChosenListBox chosen = new ChosenListBox(true); 
    // init default place holder text 
    chosen.setPlaceholderText("Choose your favourite chart..."); 
    chosen.setWidth("300px"); 
    chosen.setMaxSelectedOptions(4); 
    chosen.addChosenChangeHandler(new ChosenChangeHandler() 
    { 
     public void onChange(ChosenChangeEvent event) 
     { 
     } 
    }); 
    chosen.addGroup("Simple"); 
    chosen.addItemToGroup("line"); 
    chosen.addItemToGroup("bar"); 
    chosen.addItemToGroup("pie"); 
    chosen.addItemToGroup("area"); 

    //StackPanel stackpanel = new StackPanel(); 
    //stackpanel.add(chosen, "Choose"); 
    //stackpanel.add(wrapper, "Charts"); 
    //stackpanel.setHeight("150px"); 
    //RootPanel.get().add(stackpanel); 

    StackLayoutPanel stackLayoutPanel = new StackLayoutPanel(Unit.EM); 
    stackLayoutPanel.add(chosen, "Choose", 2); 
    stackLayoutPanel.setHeight("150px"); 
    RootLayoutPanel.get().add(stackLayoutPanel); 
}

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