Call a delegate within a delegate

Development Programming & Scripting C++
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1

I’m developing a Game in Unreal 5.1 which uses a geolocation service to get the latitude and longitude of the player’s computer.

Here it’s the header file:

#pragma once

#include "CoreMinimal.h"
#include "GameFramework/Actor.h"
#include "Runtime/Online/HTTP/Public/Http.h"
#include "PlayerGeoLocationActor.generated.h"

// Delegate signature
DECLARE_DYNAMIC_DELEGATE_TwoParams(FOnGetGeoLocationSignature, double, Latitude, double, Longitude);

UCLASS()
class PLANETARIUMSTARSTEST_API APlayerGeoLocationActor : public AActor
{
	GENERATED_BODY()
	
public:	
	// Sets default values for this actor's properties
	APlayerGeoLocationActor();

protected:
	// Called when the game starts or when spawned
	virtual void BeginPlay() override;

public:	
	// Called every frame
	virtual void Tick(float DeltaTime) override;

	FOnGetGeoLocationSignature OnGetGeoLocationDelegate;

private:
	void SendGetHttpRequest(const FString& Url);

	/*Called when the server has responded to our http request*/
	void OnResponseReceived(FHttpRequestPtr Request, FHttpResponsePtr Response, bool bWasSuccessful);

};

And the code file:

    #include "PlayerGeoLocationActor.h"
    #include "Serialization/JsonSerializer.h"
    
    // Sets default values
    APlayerGeoLocationActor::APlayerGeoLocationActor()
    {
     	// Set this actor to call Tick() every frame.  You can turn this off to improve performance if you don't need it.
    	PrimaryActorTick.bCanEverTick = true;
    
    }
    
    // Called when the game starts or when spawned
    void APlayerGeoLocationActor::BeginPlay()
    {
    	Super::BeginPlay();
    	
    }
    
    // Called every frame
    void APlayerGeoLocationActor::Tick(float DeltaTime)
    {
    	Super::Tick(DeltaTime);
    
    }
    
    void APlayerGeoLocationActor::SendGetHttpRequest(const FString& Url)
    {
    	// Create Request.
    	TSharedRef<IHttpRequest> Request = FHttpModule::Get().CreateRequest();
    
    	// Binding a function that will fire when we receive a response from our
    	// request.
    	Request->OnProcessRequestComplete().BindUObject(
    		this,
    		&APlayerGeoLocationActor::OnResponseReceived);
    
    	// This is the url on which to process the request
    	Request->SetURL(Url);
    
    	// We're getting data so set the Http method to GET.
    	Request->SetVerb("GET");
    
    	Request->SetHeader("User-Agent", "X-UnrealEngine-Agent");
    	Request->SetHeader("Content-Type", "application/json");
    	Request->ProcessRequest();
    }
    
    void APlayerGeoLocationActor::OnResponseReceived(
    	FHttpRequestPtr Request,
    	FHttpResponsePtr Response,
    	bool bWasSuccessful)
    {
    	if (bWasSuccessful)
    	{
    		// Single json value (any of supported json types e.g.
    		// object with properties, array, bool) at top level of json.
    		TSharedPtr<FJsonValue> JsonValue;
    
    		FString JsonResponse = Response->GetContentAsString();
    
    		// Create a reader pointer to read the json data
    		TSharedRef<TJsonReader<>> Reader =
    			TJsonReaderFactory<>::Create(JsonResponse);
    
    		// Deserialize the json data given Reader and the actual object to
    		// deserialize.
    		if (FJsonSerializer::Deserialize(Reader, JsonValue)) {
    			// Get the value of the json object by field name
    			double Latitude = JsonValue->AsObject()->GetNumberField("latitude");
    			double Longitude = JsonValue->AsObject()->GetNumberField("longitude");

			OnGetGeoLocationDelegate.ExecuteIfBound(Latitude, Longitude);
    		}
    	}
    }

The above code is a class that manages get the player’s location.

I have a design question: I don’t know what to do when I deserialize the latitude and logitude.

I’ve though to use a delegate and called after I get the two values.

Is it a good design to do it this way? I’m calling OnGetGeoLocationDelegate.ExecuteIfBound(Latitude, Longitude); within APlayerGeoLocationActor::OnResponseReceived.

I am in doubt because I’m going to call a delegate within a delegate. Or maybe I’m not doing that and I haven’t understood anything.

Thanks.