Adding in Steam Notifications Subsystem

Adding in Steam Notifications Subsystem, For now it just adds the OnOverlayActivated event, but it is expandable into the future being a subsystem.

AdvancedSteamSessions/Source/AdvancedSteamSessions/Classes/SteamNotificationsSubsystem.h

@@ -0,0 +1,90 @@
+// Fill out your copyright notice in the Description page of Project Settings.
+
+#pragma once
+
+#include "CoreMinimal.h"
+#include "Subsystems/GameInstanceSubsystem.h"
+
+#if PLATFORM_WINDOWS || PLATFORM_MAC || PLATFORM_LINUX
+
+#include "OnlineSubsystemSteam.h"
+#include "OnlineSubsystemSteamPrivate.h"
+
+#include <steam/steam_api.h>
+
+#endif
+
+#include "SteamNotificationsSubsystem.generated.h"
+
+DECLARE_DYNAMIC_MULTICAST_DELEGATE_OneParam(FOnSteamOverlayActivated, bool, bOverlayState);
+
+UCLASS()
+class ADVANCEDSTEAMSESSIONS_API USteamNotificationsSubsystem : public UGameInstanceSubsystem
+{
+	GENERATED_BODY()
+
+public:
+	
+	// Event thrown when the steam overlay switches states
+	UPROPERTY(BlueprintAssignable, Category = "SteamEvents")
+		FOnSteamOverlayActivated OnSteamOverlayActivated_Bind;
+	
+	USteamNotificationsSubsystem() : Super()
+	{
+
+	}
+
+	class cSteamEventsStore
+	{
+	public:
+		USteamNotificationsSubsystem* ParentSubsystem = nullptr;
+		void Initialize(USteamNotificationsSubsystem* MyParent)
+		{
+			ParentSubsystem = MyParent;
+		}
+
+#if PLATFORM_WINDOWS || PLATFORM_MAC || PLATFORM_LINUX
+		cSteamEventsStore() :
+		OnExternalUITriggeredCallback(this, &cSteamEventsStore::OnExternalUITriggered)
+		{
+
+		}
+#else
+		cSteamEventsStore() :
+		{
+
+		}
+#endif
+
+		~cSteamEventsStore(){}
+
+	private:
+#if PLATFORM_WINDOWS || PLATFORM_MAC || PLATFORM_LINUX
+		STEAM_CALLBACK(cSteamEventsStore, OnExternalUITriggered, GameOverlayActivated_t, OnExternalUITriggeredCallback);
+#endif
+	};
+
+	cSteamEventsStore MyEvents;
+
+	/** Implement this for initialization of instances of the system */
+	virtual void Initialize(FSubsystemCollectionBase& Collection) override
+	{
+		MyEvents.Initialize(this);
+	}
+
+	/** Implement this for deinitialization of instances of the system */
+	virtual void Deinitialize() override
+	{
+
+	}
+};
+
+#if PLATFORM_WINDOWS || PLATFORM_MAC || PLATFORM_LINUX
+void USteamNotificationsSubsystem::cSteamEventsStore::OnExternalUITriggered(GameOverlayActivated_t* CallbackData)
+{
+	if (ParentSubsystem)
+	{
+		ParentSubsystem->OnSteamOverlayActivated_Bind.Broadcast((bool)CallbackData->m_bActive);
+	}
+}
+#endif