_pAttachObject addExtensionSection canDelete claimChildren delegateName doubleClicked finishRestoring getAttachIDocumentObject getMDIView getViewProvider hide m_pViewProviewr setAttach setViewProvider show viewProviderCreating viewProviderIsBeingDestructed ViewProviderObserverDelegate viewProviderOnChange ~ViewProviderObserverDelegate

addExtensionSection() virtual void addExtensionSection ( ) virtual 添加扩展部分 在视图提供者中添加扩展部分，例如自定义的 UI 元素。