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Weird slew of errors when trying to make a blueprint function library for UMG?

I don’t even begin understand what im supposed to do with these errors. Its one of those errors that I normally fix because I forgot an include statement or something but that doesnt seem to be the case this time


 WidgetHelpers.cpp.obj : error LNK2019: unresolved external symbol "__declspec(dllimport) public: class UPanelWidget * __cdecl UWidget::GetParent(void)const " (__imp_?GetParent@UWidget@@QEBAPEAVUPanelWidget@@XZ) referenced in function "public: static class UUserWidget * __cdecl UWidgetHelpers::GetParentUserWidget(class UWidget *)" (?GetParentUserWidget@UWidgetHelpers@@SAPEAVUUserWidget@@PEAVUWidget@@@Z)

WidgetHelpers.cpp.obj : error LNK2019: unresolved external symbol "__declspec(dllimport) private: static class UClass * __cdecl UUserWidget::GetPrivateStaticClass(void)" (__imp_?GetPrivateStaticClass@UUserWidget@@CAPEAVUClass@@XZ) referenced in function "public: static class UUserWidget * __cdecl UWidgetHelpers::GetParentUserWidget(class UWidget *)" (?GetParentUserWidget@UWidgetHelpers@@SAPEAVUUserWidget@@PEAVUWidget@@@Z)

WidgetHelpers.cpp.obj : error LNK2019: unresolved external symbol "__declspec(dllimport) private: static class UClass * __cdecl UWidgetTree::GetPrivateStaticClass(void)" (__imp_?GetPrivateStaticClass@UWidgetTree@@CAPEAVUClass@@XZ) referenced in function "public: static class UUserWidget * __cdecl UWidgetHelpers::GetParentUserWidget(class UWidget *)" (?GetParentUserWidget@UWidgetHelpers@@SAPEAVUUserWidget@@PEAVUWidget@@@Z)

WidgetHelpers.gen.cpp.obj : error LNK2019: unresolved external symbol "__declspec(dllimport) class UClass * __cdecl Z_Construct_UClass_UUserWidget_NoRegister(void)" (__imp_?Z_Construct_UClass_UUserWidget_NoRegister@@YAPEAVUClass@@XZ) referenced in function "void __cdecl `dynamic initializer for 'public: static struct UE4CodeGen_Private::FObjectPropertyParams const Z_Construct_UFunction_UWidgetHelpers_GetParentUserWidget_Statics::NewProp_ReturnValue''(void)" (??__E?NewProp_ReturnValue@Z_Construct_UFunction_UWidgetHelpers_GetParentUserWidget_Statics@@2UFObjectPropertyParams@UE4CodeGen_Private@@B@@YAXXZ)

WidgetHelpers.gen.cpp.obj : error LNK2019: unresolved external symbol "__declspec(dllimport) class UClass * __cdecl Z_Construct_UClass_UWidget_NoRegister(void)" (__imp_?Z_Construct_UClass_UWidget_NoRegister@@YAPEAVUClass@@XZ) referenced in function "void __cdecl `dynamic initializer for 'public: static struct UE4CodeGen_Private::FObjectPropertyParams const Z_Construct_UFunction_UWidgetHelpers_GetParentUserWidget_Statics::NewProp_InputWidget''(void)" (??__E?NewProp_InputWidget@Z_Construct_UFunction_UWidgetHelpers_GetParentUserWidget_Statics@@2UFObjectPropertyParams@UE4CodeGen_Private@@B@@YAXXZ)

C:\Users\Ean\Documents\Unreal Projects\PetShip\Binaries\Win64\UE4Editor-PetShip-4150.dll : fatal error LNK1120: 5 unresolved externals



[HR][/HR]
I usually stick to blueprints when it comes to widgets for this exact reason. What Im trying to do is make a “helper library” for widgets. Just some basic things like “get the parent user widget” or “grab hud from widget” this is what I have so far


#pragma once

#include "CoreMinimal.h"
#include "Kismet/BlueprintFunctionLibrary.h"
#include "WidgetHelpers.generated.h"

class UWidget;
class UUserWidget;
/**
*
*/
UCLASS()
class PETSHIP_API UWidgetHelpers : public UBlueprintFunctionLibrary
{
GENERATED_BODY()


public:

UFUNCTION(BlueprintCallable, Category = "WidgetHelper")
static UUserWidget* GetParentUserWidget(UWidget* InputWidget);
};


Thats the header. I knew it’d be kind of funky because I don’t make too many utility classes and when I do its normally a blueprint library, but UWidgetTree is something that can only be accessed via cpp so i have my hands tied. Heres the cpp file


#include "WidgetHelpers.h"
#include "Components/Widget.h"
#include "Blueprint/WidgetTree.h"
#include "Blueprint/UserWidget.h"
#include "UMG/Public/UMG.h"



UUserWidget* UWidgetHelpers::GetParentUserWidget(UWidget* InputWidget)
{
if (InputWidget) {

UWidget* nextParentWidget = InputWidget->GetParent();
UWidget* parentwidget = nextParentWidget;

if (nextParentWidget)
{
while (nextParentWidget != nullptr)
{
nextParentWidget = parentwidget->GetParent();

if (nextParentWidget)
parentwidget = nextParentWidget;
}
}

if (parentwidget)
{
UObject* parentObject = InputWidget->GetOuter();

if (parentObject)
{
UWidgetTree* tree = Cast<UWidgetTree>(parentObject);

if (tree)
{
UObject* ParentOfTree = tree->GetOuter();

if (ParentOfTree)
{
UUserWidget* userwidget = Cast<UUserWidget>(ParentOfTree);

if (userwidget)
return userwidget;
else
return nullptr;
}
}
}
else {
return nullptr;
}
}
}
return nullptr;
}


the functionality is probably skewered and needs some work but does anyone know what may be causing these strange errors? much appreciated for any help.

Make sure that you have the proper modules included for your project in the .Build.cs file. For widgets, that would be “UMG”.


PrivateDependencyModuleNames.AddRange(new string] { "UMG" });

Thank you so much mysterious internet friend. Like that all my errors are gone. Ive only vaguely heard of the mysterious build.cs file before hand so it gives me something new about the engine to look at too. Cheers