Wtf is this error?

Development Programming & Scripting
1

Soooo, one more question. When I build or compile my project, everything is ok, but when I test my function in game, it crashes and gives me this:

Unhandled Exception: EXCEPTION_ACCESS_VIOLATION reading address 0x0000000000000448

UE4Editor_MyProject_0010!AMyCharacterCPP::Use() [C:\Users\keyni\Documents\Unreal Projects\MyProject\Source\MyProject\MyCharacterCPP.cpp:152]
UE4Editor_Engine!FInputActionUnifiedDelegate::Execute() [D:\Build\++UE4\Sync\Engine\Source\Runtime\Engine\Classes\Components\InputComponent.h:288]
UE4Editor_Engine!UPlayerInput::ProcessInputStack() [D:\Build\++UE4\Sync\Engine\Source\Runtime\Engine\Private\UserInterface\PlayerInput.cpp:1384]
UE4Editor_Engine!APlayerController::ProcessPlayerInput() [D:\Build\++UE4\Sync\Engine\Source\Runtime\Engine\Private\PlayerController.cpp:2536]
UE4Editor_Engine!APlayerController::TickPlayerInput() [D:\Build\++UE4\Sync\Engine\Source\Runtime\Engine\Private\PlayerController.cpp:4555]
UE4Editor_Engine!APlayerController::PlayerTick() [D:\Build\++UE4\Sync\Engine\Source\Runtime\Engine\Private\PlayerController.cpp:2184]
UE4Editor_Engine!APlayerController::TickActor() [D:\Build\++UE4\Sync\Engine\Source\Runtime\Engine\Private\PlayerController.cpp:4707]
UE4Editor_Engine!FActorTickFunction::ExecuteTick() [D:\Build\++UE4\Sync\Engine\Source\Runtime\Engine\Private\Actor.cpp:172]
UE4Editor_Engine!FTickFunctionTask::DoTask() [D:\Build\++UE4\Sync\Engine\Source\Runtime\Engine\Private\TickTaskManager.cpp:284]
UE4Editor_Engine!TGraphTask<FTickFunctionTask>::ExecuteTask() [D:\Build\++UE4\Sync\Engine\Source\Runtime\Core\Public\Async\TaskGraphInterfaces.h:886]
UE4Editor_Core!FNamedTaskThread::ProcessTasksNamedThread() [D:\Build\++UE4\Sync\Engine\Source\Runtime\Core\Private\Async\TaskGraph.cpp:710]
UE4Editor_Core!FNamedTaskThread::ProcessTasksUntilQuit() [D:\Build\++UE4\Sync\Engine\Source\Runtime\Core\Private\Async\TaskGraph.cpp:602]
UE4Editor_Core!FTaskGraphImplementation::WaitUntilTasksComplete() [D:\Build\++UE4\Sync\Engine\Source\Runtime\Core\Private\Async\TaskGraph.cpp:1532]
UE4Editor_Engine!FTickTaskSequencer::ReleaseTickGroup() [D:\Build\++UE4\Sync\Engine\Source\Runtime\Engine\Private\TickTaskManager.cpp:564]
UE4Editor_Engine!FTickTaskManager::RunTickGroup() [D:\Build\++UE4\Sync\Engine\Source\Runtime\Engine\Private\TickTaskManager.cpp:1585]
UE4Editor_Engine!UWorld::RunTickGroup() [D:\Build\++UE4\Sync\Engine\Source\Runtime\Engine\Private\LevelTick.cpp:785]
UE4Editor_Engine!UWorld::Tick() [D:\Build\++UE4\Sync\Engine\Source\Runtime\Engine\Private\LevelTick.cpp:1494]
UE4Editor_UnrealEd!UEditorEngine::Tick() [D:\Build\++UE4\Sync\Engine\Source\Editor\UnrealEd\Private\EditorEngine.cpp:1736]
UE4Editor_UnrealEd!UUnrealEdEngine::Tick() [D:\Build\++UE4\Sync\Engine\Source\Editor\UnrealEd\Private\UnrealEdEngine.cpp:426]
UE4Editor!FEngineLoop::Tick() [D:\Build\++UE4\Sync\Engine\Source\Runtime\Launch\Private\LaunchEngineLoop.cpp:4921]
UE4Editor!GuardedMain() [D:\Build\++UE4\Sync\Engine\Source\Runtime\Launch\Private\Launch.cpp:178]
UE4Editor!GuardedMainWrapper() [D:\Build\++UE4\Sync\Engine\Source\Runtime\Launch\Private\Windows\LaunchWindows.cpp:137]
UE4Editor!LaunchWindowsStartup() [D:\Build\++UE4\Sync\Engine\Source\Runtime\Launch\Private\Windows\LaunchWindows.cpp:273]
UE4Editor!WinMain() [D:\Build\++UE4\Sync\Engine\Source\Runtime\Launch\Private\Windows\LaunchWindows.cpp:320]
UE4Editor!__scrt_common_main_seh() [d:\agent\_work\5\s\src\vctools\crt\vcstartup\src\startup\exe_common.inl:288]
kernel32
ntdll

What I want to do:
when I look on door in game and click ‘E’, Widget has to play animation of fade, I have to telport to another side of door, and play animation in Reverse mode.
Here is line with problem:

FadeWidget->PlayAnimation(FadeWidget->FadeAnim, 0.0, 1, EUMGSequencePlayMode::Forward, 1.0);

FadeWidget here is reference to widget, and FadeAnim is variable, signed in this 2 lines in CustomUserWidget.h(class of FadeWidget):

UPROPERTY(BlueprintReadWrite, Transient, meta = (BindWidgetAnim))
		UWidgetAnimation* FadeAnim;

And also this is animation in Designer tab of BP class, based on CustomUserWidget.h:

Untitled
Untitled1920×981 236 KB

Hope that’s enough to solve my problem, but if you want something else, you’re welcome.

Thanks in advance.

2

If this is the line that fails, then probably FadeWidget is nullptr here
Do you have any checks if FadeWidget is valid before you call the function on it?

1 Like
3

Yeah, I understood, that the problem is that FadeWidget equalls nullptr.
Here is the line with creating FadeWidget:

FadeWidget = CreateWidget<UCustomUserWidget>(GetWorld(), FadeWidgetClass);

FadeWidgetClass is signed in header of Player Controller this way(I found it in one tutorial, thought it will work):

UPROPERTY(EditDefaultsOnly, Category = "Widgets")
		TSubclassOf<UUserWidget> FadeWidgetClass;

In game it doesn’t create widget, and after closing window with game there is error message in the Message Log:
Abstract, Deprecated or Replaced classes are not allowed to be used to construct a user widget. CustomUserWidget is one of these.
So, what’s the problem with this line? How can I fix it? Sorry, I’m new into Unreal, so Idk many things.

4

Your class is UUserWidget, but you’re trying to create UCustomUserWidget;
Make it
FadeWidget = CreateWidget<UUserWidget>(GetWorld(), FadeWidgetClass);

1 Like
5

It says a value of type "UUserWidget *" cannot be assigned to an entity of type "UCustomUserWidget *"

6

Is FadeWidget in .h file declared as UCustomUserWidget* FadeWidget?
If so, change it to UCustomUser* FadeWidget as well.

7

maybe you wanted to say UUserWidget* FadeWidget?
But if I’m right, I will not be able to use UCustomUserWidget’s FadeAnim BindWidgetAnim.

8

Yeah, sorry, deleted the wrong word =)

What is UCustomUserWidget anyway? I can see it’s mentioned here and there on the Internet, but I can’t find it neither in the official documentation nor in the source cpp classes.

Or is it a class you created yourself?

9

Yeah. Do you need anything from it?

10

Ah, okay, it’s your own class, it makes sense now.
Then use it in every spot you have.
.h:

UCustomUserWidget* FadeWidget;
TSubclassOf<UCustomUserWidget> FadeWidgetClass;

.cpp:
FadeWidget = CreateWidget<UCustomUserWidget>(GetWorld(), FadeWidgetClass);

1 Like
11

It says CreateWidget called with a null class about FadeWidgetClass. That’s why it skipped line with playing animation. How can I fix it, and why is it problem?