すべてを統合する - フレンドリスト - (Unreal Engine モジュール)

Last updated on October 23, 2024

Connect the UI to get friend list

1. Open the FriendsWidget_Starter class CPP file, navigate to the GetFriendList() function, and replace the current implementation with the code below. It will get the friend list using the FriendsSubsystem_Starter and then display it upon completion.

   void UFriendsWidget_Starter::GetFriendList()
   {
       ensure(FriendsSubsystem);
   
       Ws_Friends->SetWidgetState(EAccelByteWarsWidgetSwitcherState::Loading);
   
       FriendsSubsystem->GetFriendList(
           GetOwningPlayer(),
           FOnGetFriendListComplete::CreateWeakLambda(this, [this](bool bWasSuccessful, TArray<UFriendData*> Friends, const FString& ErrorMessage)
           {
               Tv_Friends->ClearListItems();
   
               if (bWasSuccessful) 
               {
                   Tv_Friends->SetListItems(Friends);
                   Ws_Friends->SetWidgetState(Friends.IsEmpty() ?
                       EAccelByteWarsWidgetSwitcherState::Empty :
                       EAccelByteWarsWidgetSwitcherState::Not_Empty);
               }
               else
               {
                   Ws_Friends->ErrorMessage = FText::FromString(ErrorMessage);
                   Ws_Friends->SetWidgetState(EAccelByteWarsWidgetSwitcherState::Error);
               }
           }
       ));
   }

2. Add the code below to the NativeOnActivated(). It will bind the GetFriendList function to the OnCachedFriendsDataUpdated, updating the displayed list as soon as the actual list changes.

   void UFriendsWidget_Starter::NativeOnActivated()
   {
       Super::NativeOnActivated();
   
       Btn_Back->OnClicked().AddUObject(this, &ThisClass::DeactivateWidget);
   
       // Reset widgets.
       Ws_Friends->SetWidgetState(EAccelByteWarsWidgetSwitcherState::Empty);
       Tv_Friends->ClearListItems();
   
       Tv_Friends->OnItemClicked().AddUObject(this, &ThisClass::OnFriendEntryClicked);
       
       FriendsSubsystem->BindOnCachedFriendsDataUpdated(GetOwningPlayer(), FOnCachedFriendsDataUpdated::CreateUObject(this, &ThisClass::GetFriendList));
       GetFriendList();
   }

3. In NativeOnDeactivated(), add the code below. Essentially, it will stop listening to the friend list changes upon the widget closing.

   void UFriendsWidget_Starter::NativeOnDeactivated()
   {
       Btn_Back->OnClicked().Clear();
   
       Tv_Friends->OnItemClicked().Clear();
   
       FriendsSubsystem->UnbindOnCachedFriendsDataUpdated(GetOwningPlayer());
   
       Super::NativeOnDeactivated();
   }

Resources

• The files used in this tutorial section are available in the Unreal Byte Wars GitHub repository.
  • AccelByteWars/Source/AccelByteWars/TutorialModules/Social/FriendsEssentials/UI/FriendsWidget_Starter.h
  • AccelByteWars/Source/AccelByteWars/TutorialModules/Social/FriendsEssentials/UI/FriendsWidget_Starter.cpp