INotifyPropertyChanged.h

#pragma once
 
#include "Event.h"
#include "Reflection.h"
 
namespace sw
{
    class INotifyPropertyChanged; // 向前声明
 
    struct PropertyChangedEventArgs : EventArgs {
        FieldId propertyId;
    };
 
    using PropertyChangedEventHandler =
        EventHandler<INotifyPropertyChanged, PropertyChangedEventArgs>;
 
    class INotifyPropertyChanged
    {
    public:
        const Event<PropertyChangedEventHandler> PropertyChanged{
            Event<PropertyChangedEventHandler>::Init(this)
                .Delegate([](INotifyPropertyChanged *self) -> PropertyChangedEventHandler & {
                    return self->GetPropertyChangedEventDelegate();
                }) //
        };
 
        virtual ~INotifyPropertyChanged() = default;
 
    protected:
        virtual PropertyChangedEventHandler &GetPropertyChangedEventDelegate() = 0;
    };
}