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Last updated on March 24, 2025

Connect the UI to search player and send friend request

Open the FindFriendsWidget_Starter class header file. You will define several new functions to call the subsystem.

protected:
// ...
	void DisplaySelfFriendCode();

	void FindFriendByDisplayName(const FString& DisplayName);
	void SendFriendRequestByFriendCode(const FString& FriendCode);

Open the FindFriendsWidget_Starter class CPP file and define the DisplaySelfFriendCode() function. This function will retrieve the player's friend code and display it on the UI.

void UFindFriendsWidget_Starter::DisplaySelfFriendCode()
{
	Tb_FriendCode->SetText(FText::GetEmpty());
	Ws_FriendCode->SetActiveWidget(Th_FriendCodeLoader);

	FriendsSubsystem->GetSelfFriendCode(
		GetOwningPlayer(),
		FOnGetSelfFriendCodeComplete::CreateWeakLambda(this, [this](bool bWasSuccessful, UFriendData* FriendData, const FString& FriendCode)
		{
			if (bWasSuccessful && !FriendCode.IsEmpty())
			{
				Tb_FriendCode->SetText(FText::FromString(FriendCode));
				Ws_FriendCode->SetActiveWidget(Tb_FriendCode);
			}
			else
			{
				Ws_FriendCode->SetActiveWidget(Tb_FriendCodeEmpty);
			}
		}
	));
}

Define the FindFriendByDisplayName() function which will trigger the subsystem's FindFriend() function and display the retrieved friend information in the UI.

void UFindFriendsWidget_Starter::FindFriendByDisplayName(const FString& DisplayName)
{
	ensure(FriendsSubsystem);

	Ws_FindFriends->SetWidgetState(EAccelByteWarsWidgetSwitcherState::Loading);

	// Try to find friend by exact display name.
	FriendsSubsystem->FindFriend(
		GetOwningPlayer(),
		DisplayName,
		FOnFindFriendComplete::CreateWeakLambda(this, [this](bool bWasSuccessful, UFriendData* FriendData, const FString& ErrorMessage)
		{
			Lv_FindFriends->SetUserFocus(GetOwningPlayer());
			Lv_FindFriends->ClearListItems();

			if (bWasSuccessful)
			{
				// Reset the status to be "searched", because the data is retrieved from the result of find friend.
				FriendData->Status = EFriendStatus::Searched;
				Lv_FindFriends->AddItem(FriendData);
				Lv_FindFriends->RequestRefresh();
				Ws_FindFriends->SetWidgetState(EAccelByteWarsWidgetSwitcherState::Not_Empty);
			}
			else
			{
				Ws_FindFriends->ErrorMessage = FText::FromString(ErrorMessage);
				Ws_FindFriends->SetWidgetState(EAccelByteWarsWidgetSwitcherState::Error);
			}
		}
	));
}

Define the SendFriendRequestByFriendCode() function which will send the friend request using SendFriendRequest immediately. However, if it fails, it will take the entered friend code and use it as a display name to search for the player.

void UFindFriendsWidget_Starter::SendFriendRequestByFriendCode(const FString& FriendCode)
{
	// Abort if trying to friend with themself.
	if (FriendCode.Equals(Tb_FriendCode->GetText().ToString())) 
	{
		Ws_FindFriends->ErrorMessage = CANNOT_INVITE_FRIEND_SELF;
		Ws_FindFriends->SetWidgetState(EAccelByteWarsWidgetSwitcherState::Error);
		return;
	}

	ensure(FriendsSubsystem);

	Ws_FindFriends->SetWidgetState(EAccelByteWarsWidgetSwitcherState::Loading);

	// Try to send friend request by friend code.
	FriendsSubsystem->SendFriendRequest(
		GetOwningPlayer(),
		FriendCode,
		FOnSendFriendRequestComplete::CreateWeakLambda(this, [this](bool bWasSuccessful, UFriendData* FriendData, const FString& ErrorMessage)
		{
			Lv_FindFriends->SetUserFocus(GetOwningPlayer());
			Lv_FindFriends->ClearListItems();

			if (!bWasSuccessful && !FriendData) 
			{
				/* Fallback, the player might enter display name instead of friend code.
				 * Try to find friend by the exact display name. */
				FindFriendByDisplayName(Edt_SearchBar->GetText().ToString());
			}
			else 
			{
				// Reset the status to be "searched", because the data is retrieved from the result of find friend.
				FriendData->Status = EFriendStatus::Searched;
				Lv_FindFriends->AddItem(FriendData);
				Lv_FindFriends->RequestRefresh();
				Ws_FindFriends->SetWidgetState(EAccelByteWarsWidgetSwitcherState::Not_Empty);
			}
		}
	));
}

Still in the FindFriendsWidget_Starter class CPP file, navigate to the NativeOnActivated() function, which will be called upon the widget opening, and replace it with the code below. This will trigger DisplaySelfFriendCode immediately upon the widget activating.

void UFindFriendsWidget_Starter::NativeOnActivated()
{
	Super::NativeOnActivated();

	Btn_Back->OnClicked().AddUObject(this, &ThisClass::DeactivateWidget);

	Edt_SearchBar->SetText(FText::FromString(TEXT("")));
	Edt_SearchBar->OnTextCommitted.AddDynamic(this, &ThisClass::OnSearchBarCommitted);
	Btn_Search->OnClicked().AddWeakLambda(this, [this]()
	{
		OnSearchBarCommitted(Edt_SearchBar->GetText(), ETextCommit::Type::OnEnter);
	});
	Btn_CopyFriendCode->OnClicked().AddUObject(this, &ThisClass::CopyFriendCodeToClipboard);

	// Reset widgets.
	Ws_FindFriends->SetWidgetState(EAccelByteWarsWidgetSwitcherState::Empty);
	Lv_FindFriends->ClearListItems();

	DisplaySelfFriendCode();
}

In the FindFriendsWidget_Starter class CPP file, navigate to the OnSearchBarCommitted() function and replace the current implementation with the code below. At first, the logic will treat any given text as a friend code, and if it fails, it will treated as display name. Once complete, it will show the result.
```
void UFindFriendsWidget_Starter::OnSearchBarCommitted(const FText& Text, ETextCommit::Type CommitMethod)
{
	if (CommitMethod != ETextCommit::Type::OnEnter || Text.IsEmpty())
	{
		return;
	}

	SendFriendRequestByFriendCode(Text.ToString());
}
```

Open the FriendWidgetEntry_Starter class CPP file, navigate to OnInviteButtonClicked(), and replace the current implementation with the code below. It will send a friend invitation request using the FriendsSubsystem_Starter subsystem.

void UFriendWidgetEntry_Starter::OnInviteButtonClicked()
{
	ensure(CachedFriendData);
	ensure(FriendsSubsystem);

	FriendsSubsystem->SendFriendRequest(
		GetOwningPlayer(), 
		CachedFriendData->UserId, 
		FOnSendFriendRequestComplete::CreateWeakLambda(this, [this](bool bWasSuccessful, UFriendData* FriendData, const FString& ErrorMessage) 
		{
			if (bWasSuccessful) 
			{
				// Since the invitation is already sent, refresh the entry data to show that the friend cannot be invited again.
				CachedFriendData->bCannotBeInvited = FriendData->bCannotBeInvited;
				CachedFriendData->ReasonCannotBeInvited = FriendData->ReasonCannotBeInvited;
				NativeOnListItemObjectSet(CachedFriendData);
			}
		}
	));
}

Compile your project and make sure there are no errors.

Resources

The files used in this tutorial section are available in the Unreal Byte Wars GitHub repository.

Connect the UI to search player and send friend request​

Resources​

Connect the UI to search player and send friend request

Resources