Read receipts

Required setup

Read Receipts requires Unread Message Count. First, set the last read timetoken for each user on a channel.

Read receipts show if channel members have viewed a message.

You can use PubNub's functionality via Blueprints or directly in C++ code.

• In Blueprints, the whole SDK is managed by a subsystem, so start by initalizing the PubnubChatSubsystem node. Afterwards, you can use the Pubnub Chat object reference.

Blueprint functions

The Blueprints provided in the documentation show how you can structure your application and may contain utility methods and elements like buttons that are not part of the Unreal Chat SDK and are meant to serve as guidance.

• In C++, you can use the PubNub SDK as any other Game Instance Subsystem.

  #include "Kismet/GameplayStatics.h"
  #include "PubnubChatSubsystem.h"
  
  
  UGameInstance* GameInstance = UGameplayStatics::GetGameInstance(this);
  UPubnubChatSubsystem* PubnubChatSubsystem = GameInstance->GetSubsystem<UPubnubChatSubsystem>();
  
  
  UPubnubChat* Chat = PubnubChatSubsystem ->InitChat("demo", "demo", "my_user") // config optional

  Chat now allows you to call all Chat SDK functions, for example:

  Chat->DeleteUser("SomeUserID");

Usage in Blueprints and C++

Get read receipts

StreamReadReceipts() provides read status for messages on a channel. The method fetches member read status, listens for updates, and passes receipt events to your callback.

Not available for public chats

Read receipts are disabled in public chats.

Method signature

Blueprint

C++ / Input parameters

1Channel->StreamReadReceipts(FOnPubnubChannelStreamReadReceiptsReceived ReadReceiptsCallback);

* required

Parameter	Description
ReadReceiptsCallback * Type: FOnPubnubChannelStreamReadReceiptsReceived Default: n/a	Callback function passed as a parameter. It defines the custom behavior to be executed when receiving a read confirmation status on the joined channel.

Each function in the Unreal Chat SDK that takes a callback as a parameter requires you to handle the response type accordingly.

For example, you can bind a callback function for the Channel->StreamPresence method to its handler in the following way:

1// Create a pubnub response delegate
2// you MUST implement your own callback function to handle the response
3FOnPubnubChannelStreamPresenceReceived PresenceResponse;
4PresenceResponse.BindDynamic(this, &AMyActor::OnPresenceResponseReceived);
5

6Channel->StreamPresence(PresenceResponse);

You can implement the callback function to handle the response as follows:

AMyActor.h

1UFUNCTION()
2void OnPresenceResponseReceived(const TArray<FString> &PresentUsersIDs);

AMyActor.cpp

1void AMyActor::OnPresenceResponseReceived(const TArray<FString> &PresentUsersIDs)
2{
3	for(auto PresentUser : PresentUsersIDs)
4	{
5		UE_LOG(LogTemp, Log, TEXT("Present User ID: "), *PresentUser);
6	}
7}

Handle the response

Output

Type	Description
UPubnubCallbackStop*	Object on which you can call Stop() to stop receiving updates.

Sample code

Receive updates for read receipts on the support channel.

1#include "Kismet/GameplayStatics.h"
2#include "PubnubChatSubsystem.h"
3

4UGameInstance* GameInstance = UGameplayStatics::GetGameInstance(this);
5UPubnubChatSubsystem* PubnubChatSubsystem = GameInstance->GetSubsystem<UPubnubChatSubsystem>();
6

7UPubnubChat* Chat = PubnubChatSubsystem ->InitChat("demo", "demo", "my_user");
8

9UPubnubChannel* Channel = Chat->GetChannel("support");
10

11// Create a pubnub response delegate
12// you MUST implement your own callback function to handle the response
13FOnPubnubChannelStreamReadReceiptsReceived ReadReceiptsUpdatesOnResponse;
14ReadReceiptsUpdatesOnResponse.BindDynamic(this, &AMyActor::OnReadReceiptsResponseReceived);
15

16auto StopUpdates = Channel->StreamReadReceipts(ReadReceiptsUpdatesOnResponse);
17

18// after some time
19StopUpdates->Stop();

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