I can not show LoadingScreen using FLoadingScreenAttributes

I wrote the c ++ code by referring to the link above.
As a result of debugging, function binding is not a problem However, LoadingScreen did not show on the screen.

This is my code.

void UEditorGameInstance::SetLoadingScreen(UUserWidget* NewLoadingWidget) {	LoadingWidget = NewLoadingWidget; } void UEditorGameInstance::Init() {	UGameInstance::Init();	FCoreUObjectDelegates::PreLoadMap.AddUObject(this, &UEditorGameInstance::BeginLoadingScreen);	FCoreUObjectDelegates::PostLoadMap.AddUObject(this, &UEditorGameInstance::EndLoadingScreen); } void UEditorGameInstance::BeginLoadingScreen(const FString& MapName) {	FLoadingScreenAttributes LoadingScreen;	LoadingScreen.bAutoCompleteWhenLoadingCompletes = true;	if(LoadingWidget)	LoadingScreen.WidgetLoadingScreen = LoadingWidget->TakeWidget();	else	LoadingScreen.WidgetLoadingScreen = FLoadingScreenAttributes::NewTestLoadingScreenWidget();	GetMoviePlayer()->SetupLoadingScreen(LoadingScreen);	GetMoviePlayer()->PlayMovie(); } 

The function of ‘SetLoadingScreen(UUserWidget*)’ is regist my LoadingScreen widget.
Where did I get it wrong? Am I misunderstanding? How to make LoadingScreen?

I found one thing by referring to the Shooter Game today.
This LoadingScreen did not work on the editor screen.
Tested through the StandAlong Game, it worked.