Custom MarkupExtension to connect a RoutedEvent to a Command in NoesisGUI

EventBindingExtension.cpp

struct EventBindingExtension: public BaseComponent, public IMarkupExtension
{
    EventBindingExtension() { }

    const NsChar* GetCommandName() const { return commandName.c_str(); }
    void SetCommandName(const NsChar* name) { commandName = name; }

    Ptr<BaseComponent> ProvideValue(const void* context) override
    {
        auto provider = (const XamlReaderProvider*)context;
        auto element = NsDynamicCast<UIElement*>(provider->GetTargetObject());
        if (element != 0)
        {
            auto eventId = provider->GetPropertyName();
            auto type = element->GetClassType();

            // look in UIElementData for the routed event
            auto event = FindRoutedEvent(type, eventId);
            if (event != 0)
            {
                // TODO: connect event with a delegate that could resolve
                // commandName from element DataContext                 
                //element->AddHandler(event, ...);
            }
        }

        return nullptr;
    }

    NS_IMPLEMENT_INTERFACE_FIXUP

private:
    // ...
    
    NsString commandName;

    NS_IMPLEMENT_INLINE_REFLECTION(EventBindingExtension, BaseComponent)
    {
        NsMeta<TypeId>("EventBinding");
        NsMeta<ContentPropertyMetaData>("CommandName");

        NsImpl<IMarkupExtension>();

        NsProp("CommandName", &EventBindingExtension::GetCommandName,
            &EventBindingExtension::SetCommandName);
    }
};