GWTP創建新的主持人每次

Question

我：

• 簡單的嵌套主持人（ChannelPresenter），其中有表（網格），在它的記錄。我需要在每個ChannelPresenter.displayEditor（）調用中創建新的ChannelEditorPresenter實例。
• 彈出主持人小工具（ChannelEditorPresenter）應在每個ChannelEditorPresenter.edit顯示彈出式窗口（）調用

目前我注射ChannelEditorPresenter到ChannelPresenter構造，但在這種情況下，我有ChannelEditorPresenter只有一個實例。實際上，我需要爲每個呼叫單獨提供Popup演示者。 （很多分離的窗口，每個都有自己的數據）。

ChannelPresenter.java：

public class ChannelPresenter extends Presenter<ChannelPresenter.MyView, ChannelPresenter.MyProxy> implements ChannelUiHandlers { 

    public interface MyView extends View, HasUiHandlers<ChannelUiHandlers> { 
     void load(); 
    } 

    @ProxyStandard 
    @NameToken(NameTokens.CHANNELS) 
    interface MyProxy extends ProxyPlace<ChannelPresenter> { 
    } 

    ChannelEditorPresenter channelEditorPresenter; 

    @Inject 
    ChannelPresenter(EventBus eventBus, MyView view, MyProxy proxy, 
        ChannelEditorPresenter channelEditorPresenter 
        ) { 
     super(eventBus, view, proxy, ApplicationPresenter.SLOT_MAIN); 
     getView().setUiHandlers(this); 
     this.channelEditorPresenter = channelEditorPresenter; 
    } 

    @Override 
    protected void onBind() { 
     super.onBind(); 
     getView().load(); 
    } 

    @Override 
    public void displayEditor(Channel channel) { 
     // !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!! 
     // Here I need to create new instance for each call 
     // !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!! 
     addToPopupSlot(channelEditorPresenter); 
     channelEditorPresenter.edit(channel); 
    } 
} 

Answer 1

，我發現這裏的解決方案：Instantiate a PresenterWidget (GWTP) manually

我需要注入com.google.inject.Provider <ChannelEditorPresenter>而非純ChannelEditorPresenter。

ChannelPresenter.java：

public class ChannelPresenter extends Presenter<ChannelPresenter.MyView, ChannelPresenter.MyProxy> implements ChannelUiHandlers { 

    public interface MyView extends View, HasUiHandlers<ChannelUiHandlers> { 
     void load(); 
    } 

    @ProxyStandard 
    @NameToken(NameTokens.CHANNELS) 
    interface MyProxy extends ProxyPlace<ChannelPresenter> { 
    } 

    Provider<ChannelEditorPresenter> channelEditorPresenterProvider; 

    @Inject 
    ChannelPresenter(EventBus eventBus, MyView view, MyProxy proxy, 
        Provider<ChannelEditorPresenter> channelEditorPresenterProvider 
        ) { 
     super(eventBus, view, proxy, ApplicationPresenter.SLOT_MAIN); 
     getView().setUiHandlers(this); 
     this.channelEditorPresenterProvider = channelEditorPresenterProvider; 
    } 

    @Override 
    protected void onBind() { 
     super.onBind(); 
     getView().load(); 
    } 

    @Override 
    public void displayEditor(Channel channel) { 
     ChannelEditorPresenter channelEditorPresenter = channelEditorPresenterProvider.get(); 
     addToPopupSlot(channelEditorPresenter); 
     channelEditorPresenter.edit(channel); 
    } 
} 

Answer 2

最近，我們有同樣的問題，我們找到了最好的方法是使用WidgetsFactory與@Assisted註釋，如在Arcbees'的博客文章中提到：http://blog.arcbees.com/2015/04/01/gwt-platform-event-best-practices-revisited/

當您需要將不同參數傳遞給演示者小部件的構造函數時，這非常有用。