Listening for Attribute Changes

Source/Aura/Private/AbilitySystem/AuraAttributeSet.cpp

@@ -6,9 +6,9 @@
 
 UAuraAttributeSet::UAuraAttributeSet()
 {
-	InitHealth(100.f);
+	InitHealth(50.f);
 	InitMaxHealth(100.f);
-	InitMana(50.f);
+	InitMana(25.f);
 	InitMaxMana(50.f);
 }
 

Source/Aura/Private/UI/HUD/AuraHUD.cpp

@@ -14,6 +14,7 @@ UOverlayWidgetController* AAuraHUD::GetOverlayWidgetController(const FWidgetCont
 	OverlayWidgetController = NewObject<UOverlayWidgetController>(this, OverlayWidgetControllerClass);
 	OverlayWidgetController->SetWidgetControllerParams(WCParams);
 
+	OverlayWidgetController->BindCallbacksToDependencies();
 	return OverlayWidgetController;
 }
 
@@ -29,6 +30,7 @@ void AAuraHUD::InitOverlay(APlayerController* PC, APlayerState* PS, UAbilitySyst
 	const auto WidgetController = GetOverlayWidgetController(WidgetControllerParams);
 
 	OverlayWidget->SetWidgetController(WidgetController);
+	WidgetController->BroadcastInitialValues();
 	
 	Widget->AddToViewport();
 }

Source/Aura/Private/UI/WidgetController/AuraWidgetController.cpp

@@ -10,3 +10,11 @@ void UAuraWidgetController::SetWidgetControllerParams(const FWidgetControllerPar
 	AbilitySystemComponent = Params.AbilitySystemComponent;
 	AttributeSet = Params.AttributeSet;
 }
+
+void UAuraWidgetController::BroadcastInitialValues()
+{
+}
+
+void UAuraWidgetController::BindCallbacksToDependencies()
+{
+}

Source/Aura/Private/UI/WidgetController/OverlayWidgetController.cpp

@@ -3,3 +3,50 @@
 
 #include "UI/WidgetController/OverlayWidgetController.h"
 
+#include "AbilitySystem/AuraAttributeSet.h"
+
+void UOverlayWidgetController::BroadcastInitialValues()
+{
+	const auto AuraAttributeSet = CastChecked<UAuraAttributeSet>(AttributeSet);
+	OnHealthChanged.Broadcast(AuraAttributeSet->GetHealth());
+	OnMaxHealthChanged.Broadcast(AuraAttributeSet->GetMaxHealth());
+	OnManaChanged.Broadcast(AuraAttributeSet->GetMana());
+	OnMaxManaChanged.Broadcast(AuraAttributeSet->GetMaxMana());
+}
+
+void UOverlayWidgetController::BindCallbacksToDependencies()
+{
+	const UAuraAttributeSet* AuraAttributeSet = CastChecked<UAuraAttributeSet>(AttributeSet);
+
+	AbilitySystemComponent->GetGameplayAttributeValueChangeDelegate(
+		AuraAttributeSet->GetHealthAttribute()).AddUObject(this, &UOverlayWidgetController::HealthChanged);
+
+	AbilitySystemComponent->GetGameplayAttributeValueChangeDelegate(
+		AuraAttributeSet->GetMaxHealthAttribute()).AddUObject(this, &UOverlayWidgetController::MaxHealthChanged);
+
+	AbilitySystemComponent->GetGameplayAttributeValueChangeDelegate(
+		AuraAttributeSet->GetManaAttribute()).AddUObject(this, &UOverlayWidgetController::ManaChanged);
+
+	AbilitySystemComponent->GetGameplayAttributeValueChangeDelegate(
+		AuraAttributeSet->GetMaxManaAttribute()).AddUObject(this, &UOverlayWidgetController::MaxManaChanged);
+}
+
+void UOverlayWidgetController::HealthChanged(const FOnAttributeChangeData& Data) const
+{
+	OnHealthChanged.Broadcast(Data.NewValue);
+}
+
+void UOverlayWidgetController::MaxHealthChanged(const FOnAttributeChangeData& Data) const
+{
+	OnMaxHealthChanged.Broadcast(Data.NewValue);
+}
+
+void UOverlayWidgetController::ManaChanged(const FOnAttributeChangeData& Data) const
+{
+	OnManaChanged.Broadcast(Data.NewValue);
+}
+
+void UOverlayWidgetController::MaxManaChanged(const FOnAttributeChangeData& Data) const
+{
+	OnMaxManaChanged.Broadcast(Data.NewValue);
+}

Source/Aura/Public/UI/WidgetController/AuraWidgetController.h

@@ -45,6 +45,8 @@ public:
 	UFUNCTION(BlueprintCallable)
 	void SetWidgetControllerParams(const FWidgetControllerParams& Params);
 
+	virtual void BroadcastInitialValues(); 
+	virtual void BindCallbacksToDependencies();
 protected:
 	UPROPERTY(BlueprintReadOnly, Category="WidgetController")
 	TObjectPtr<APlayerController> PlayerController;

Source/Aura/Public/UI/WidgetController/OverlayWidgetController.h

@@ -6,12 +6,39 @@
 #include "UI/WidgetController/AuraWidgetController.h"
 #include "OverlayWidgetController.generated.h"
 
+DECLARE_DYNAMIC_MULTICAST_DELEGATE_OneParam(FOnHealthChangedSignature, float, NewHealth);
+DECLARE_DYNAMIC_MULTICAST_DELEGATE_OneParam(FOnMaxHealthChangedSignature, float, NewMaxHealth);
+DECLARE_DYNAMIC_MULTICAST_DELEGATE_OneParam(FOnManaChangedSignature, float, NewMana);
+DECLARE_DYNAMIC_MULTICAST_DELEGATE_OneParam(FOnMaxManaChangedSignature, float, NewMaxMana);
+
+
 /**
  * 
  */
-UCLASS()
+UCLASS(BlueprintType, Blueprintable)
 class AURA_API UOverlayWidgetController : public UAuraWidgetController
 {
 	GENERATED_BODY()
 
+public:
+	virtual void BroadcastInitialValues() override;
+	virtual void BindCallbacksToDependencies() override;
+
+	UPROPERTY(BlueprintAssignable, Category="GAS|Attributes")
+	FOnHealthChangedSignature OnHealthChanged;
+
+	UPROPERTY(BlueprintAssignable, Category="GAS|Attributes")
+	FOnMaxHealthChangedSignature OnMaxHealthChanged;
+
+	UPROPERTY(BlueprintAssignable, Category="GAS|Attributes")
+	FOnManaChangedSignature OnManaChanged;
+
+	UPROPERTY(BlueprintAssignable, Category="GAS|Attributes")
+	FOnMaxManaChangedSignature OnMaxManaChanged;
+
+protected:
+	void HealthChanged(const FOnAttributeChangeData& Data) const;
+	void MaxHealthChanged(const FOnAttributeChangeData& Data) const;
+	void ManaChanged(const FOnAttributeChangeData& Data) const;
+	void MaxManaChanged(const FOnAttributeChangeData& Data) const;
 };