Slate Link Errors

That is 76 unresolved external symbols, Do I really need to define 76 virtual functions to create a simple little widget?

//File: MyUIWidget.h

#pragma once
#include "MyHUD.h"
#include "Slate.h"

class SMyUIWidget : public SCompoundWidget
{
	SLATE_BEGIN_ARGS(SMyUIWidget)
	{}

	SLATE_ARGUMENT(TWeakObjectPtr<AMyHUD>, OwnerHUD)

	SLATE_END_ARGS()

public:
	//needed for every widget
	void Construct(const FArguments& InArgs);
private:
	//Pointer to our parent HUD
	TWeakObjectPtr<class AMyHUD> OwnerHUD;
};

//File: MyUIWidget.cpp

#include "MyProject.h"
#include "MyUIWidget.h"


void SMyUIWidget::Construct(const FArguments& InArgs)
{
	OwnerHUD = InArgs._OwnerHUD;

	ChildSlot
		.VAlign(VAlign_Fill)
		.HAlign(HAlign_Fill)
		[
			SNew(SOverlay)
			+ SOverlay::Slot()
			.VAlign(VAlign_Top)
			.HAlign(HAlign_Center)
			[
				SNew(STextBlock)
				.ShadowColorAndOpacity(FLinearColor::Black)
				.ColorAndOpacity(FLinearColor::White)
				.ShadowOffset(FIntPoint(-1, 1))
				.Font( FSlateFontInfo("Veranda", 8) )
				.Text(FString("BLAM"))
			]
		];
}


1>MyUIWidget.cpp.obj : error LNK2019: unresolved external symbol "__declspec(dllimport) public: __cdecl FSlateFontInfo::FSlateFontInfo(void)" (__imp_??0FSlateFontInfo@@QEAA@XZ) referenced in function "public: __cdecl TAttribute<struct FSlateFontInfo>::TAttribute<struct FSlateFontInfo>(void)" (??0?$TAttribute@UFSlateFontInfo@@@@QEAA@XZ)
1>MyUIWidget.cpp.obj : error LNK2019: unresolved external symbol "__declspec(dllimport) public: static struct FTextBlockStyle const & __cdecl FTextBlockStyle::GetDefault(void)" (__imp_?GetDefault@FTextBlockStyle@@SAAEBU1@XZ) referenced in function "public: struct FTextBlockStyle const & __cdecl ISlateStyle::GetWidgetStyle<struct FTextBlockStyle>(class FName,char const *)const " (??$GetWidgetStyle@UFTextBlockStyle@@@ISlateStyle@@QEBAAEBUFTextBlockStyle@@VFName@@PEBD@Z)
1>MyUIWidget.cpp.obj : error LNK2019: unresolved external symbol "__declspec(dllimport) public: static class ISlateStyle const & __cdecl FCoreStyle::Get(void)" (__imp_?Get@FCoreStyle@@SAAEBVISlateStyle@@XZ) referenced in function "public: __cdecl STextBlock::FArguments::FArguments(void)" (??0FArguments@STextBlock@@QEAA@XZ)
1>MyUIWidget.cpp.obj : error LNK2019: unresolved external symbol "__declspec(dllimport) public: static class FName __cdecl ISlateStyle::Join(class FName,char const *)" (__imp_?Join@ISlateStyle@@SA?AVFName@@V2@PEBD@Z) referenced in function "public: struct FTextBlockStyle const & __cdecl ISlateStyle::GetWidgetStyle<struct FTextBlockStyle>(class FName,char const *)const " (??$GetWidgetStyle@UFTextBlockStyle@@@ISlateStyle@@QEBAAEBUFTextBlockStyle@@VFName@@PEBD@Z)
1>MyUIWidget.cpp.obj : error LNK2019: unresolved external symbol "__declspec(dllimport) public: class FSimpleSlot & __cdecl TSupportsOneChildMixin<class SWidget,class FSimpleSlot>::operator[](class TSharedRef<class SWidget,0>)" (__imp_??A?$TSupportsOneChildMixin@VSWidget@@VFSimpleSlot@@@@QEAAAEAVFSimpleSlot@@V?$TSharedRef@VSWidget@@$0A@@@@Z) referenced in function "public: void __cdecl SMyUIWidget::Construct(struct SMyUIWidget::FArguments const &)" (?Construct@SMyUIWidget@@QEAAXAEBUFArguments@1@@Z)
1>MyUIWidget.cpp.obj : error LNK2019: unresolved external symbol "__declspec(dllimport) private: static void * __cdecl FSlateControlledConstruction::operator new(unsigned __int64)" (__imp_??2FSlateControlledConstruction@@CAPEAX_K@Z) referenced in function "public: __cdecl TDecl<class SOverlay,struct RequiredArgs::T0RequiredArgs>::TDecl<class SOverlay,struct RequiredArgs::T0RequiredArgs>(char const *,char const *,int,struct RequiredArgs::T0RequiredArgs const &)" (??0?$TDecl@VSOverlay@@UT0RequiredArgs@RequiredArgs@@@@QEAA@PEBD0HAEBUT0RequiredArgs@RequiredArgs@@@Z)
1>MyUIWidget.cpp.obj : error LNK2019: unresolved external symbol "__declspec(dllimport) public: static void __cdecl FSlateControlledConstruction::operator delete(void *)" (__imp_??3FSlateControlledConstruction@@SAXPEAX@Z) referenced in function "int `public: __cdecl TDecl<class SOverlay,struct RequiredArgs::T0RequiredArgs>::TDecl<class SOverlay,struct RequiredArgs::T0RequiredArgs>(char const *,char const *,int,struct RequiredArgs::T0RequiredArgs const &)'::`1'::dtor$0" (?dtor$0@?0???0?$TDecl@VSOverlay@@UT0RequiredArgs@RequiredArgs@@@@QEAA@PEBD0HAEBUT0RequiredArgs@RequiredArgs@@@Z@4HA)
1>MyUIWidget.cpp.obj : error LNK2019: unresolved external symbol "__declspec(dllimport) public: void __cdecl SWidget::Construct(class TAttribute<class FString> const &,class TSharedPtr<class SToolTip,0> const &,class TAttribute<struct TOptional<enum EMouseCursor::Type> > const &,class TAttribute<bool> const &,class TAttribute<struct EVisibility> const &,class FName const &)" (__imp_?Construct@SWidget@@QEAAXAEBV?$TAttribute@VFString@@@@AEBV?$TSharedPtr@VSToolTip@@$0A@@@AEBV?$TAttribute@U?$TOptional@W4Type@EMouseCursor@@@@@@AEBV?$TAttribute@_N@@AEBV?$TAttribute@UEVisibility@@@@AEBVFName@@@Z) referenced in function "public: class TSharedRef<class SOverlay,0> __cdecl TDecl<class SOverlay,struct RequiredArgs::T0RequiredArgs>::operator<<=(struct SOverlay::FArguments const &)const " (??_3?$TDecl@VSOverlay@@UT0RequiredArgs@RequiredArgs@@@@QEBA?AV?$TSharedRef@VSOverlay@@$0A@@@AEBUFArguments@SOverlay@@@Z)
1>MyUIWidget.cpp.obj : error LNK2019: unresolved external symbol "__declspec(dllimport) public: void __cdecl SWidget::SetDebugInfo(char const *,char const *,int)" (__imp_?SetDebugInfo@SWidget@@QEAAXPEBD0H@Z) referenced in function "public: __cdecl TDecl<class SOverlay,struct RequiredArgs::T0RequiredArgs>::TDecl<class SOverlay,struct RequiredArgs::T0RequiredArgs>(char const *,char const *,int,struct RequiredArgs::T0RequiredArgs const &)" (??0?$TDecl@VSOverlay@@UT0RequiredArgs@RequiredArgs@@@@QEAA@PEBD0HAEBUT0RequiredArgs@RequiredArgs@@@Z)
1>MyUIWidget.cpp.obj : error LNK2019: unresolved external symbol "__declspec(dllimport) public: class SOverlay::FOverlaySlot & __cdecl TSupportsOneChildMixin<class SWidget,class SOverlay::FOverlaySlot>::operator[](class TSharedRef<class SWidget,0>)" (__imp_??A?$TSupportsOneChildMixin@VSWidget@@VFOverlaySlot@SOverlay@@@@QEAAAEAVFOverlaySlot@SOverlay@@V?$TSharedRef@VSWidget@@$0A@@@@Z) referenced in function "public: void __cdecl SMyUIWidget::Construct(struct SMyUIWidget::FArguments const &)" (?Construct@SMyUIWidget@@QEAAXAEBUFArguments@1@@Z)
1>MyUIWidget.cpp.obj : error LNK2019: unresolved external symbol "__declspec(dllimport) public: class SOverlay::FOverlaySlot & __cdecl SOverlay::FOverlaySlot::HAlign(enum EHorizontalAlignment)" (__imp_?HAlign@FOverlaySlot@SOverlay@@QEAAAEAV12@W4EHorizontalAlignment@@@Z) referenced in function "public: void __cdecl SMyUIWidget::Construct(struct SMyUIWidget::FArguments const &)" (?Construct@SMyUIWidget@@QEAAXAEBUFArguments@1@@Z)
1>MyUIWidget.cpp.obj : error LNK2019: unresolved external symbol "__declspec(dllimport) public: class SOverlay::FOverlaySlot & __cdecl SOverlay::FOverlaySlot::VAlign(enum EVerticalAlignment)" (__imp_?VAlign@FOverlaySlot@SOverlay@@QEAAAEAV12@W4EVerticalAlignment@@@Z) referenced in function "public: void __cdecl SMyUIWidget::Construct(struct SMyUIWidget::FArguments const &)" (?Construct@SMyUIWidget@@QEAAXAEBUFArguments@1@@Z)
1>MyUIWidget.cpp.obj : error LNK2019: unresolved external symbol "__declspec(dllimport) public: virtual __cdecl SOverlay::~SOverlay(void)" (__imp_??1SOverlay@@UEAA@XZ) referenced in function "public: virtual void * __cdecl SOverlay::`scalar deleting destructor'(unsigned int)" (??_GSOverlay@@UEAAPEAXI@Z)
1>MyUIWidget.cpp.obj : error LNK2019: unresolved external symbol "__declspec(dllimport) public: void __cdecl SOverlay::Construct(struct SOverlay::FArguments const &)" (__imp_?Construct@SOverlay@@QEAAXAEBUFArguments@1@@Z) referenced in function "public: void __cdecl RequiredArgs::T0RequiredArgs::CallConstruct<class SOverlay,struct SOverlay::FArguments>(class TSharedRef<class SOverlay,0> const &,struct SOverlay::FArguments const &)const " (??$CallConstruct@VSOverlay@@UFArguments@1@@T0RequiredArgs@RequiredArgs@@QEBAXAEBV?$TSharedRef@VSOverlay@@$0A@@@AEBUFArguments@SOverlay@@@Z)
1>MyUIWidget.cpp.obj : error LNK2019: unresolved external symbol "__declspec(dllimport) public: static class SOverlay::FOverlaySlot & __cdecl SOverlay::Slot(void)" (__imp_?Slot@SOverlay@@SAAEAVFOverlaySlot@1@XZ) referenced in function "public: void __cdecl SMyUIWidget::Construct(struct SMyUIWidget::FArguments const &)" (?Construct@SMyUIWidget@@QEAAXAEBUFArguments@1@@Z)
1>MyUIWidget.cpp.obj : error LNK2019: unresolved external symbol "__declspec(dllimport) public: __cdecl SOverlay::SOverlay(void)" (__imp_??0SOverlay@@QEAA@XZ) referenced in function "public: __cdecl TDecl<class SOverlay,struct RequiredArgs::T0RequiredArgs>::TDecl<class SOverlay,struct RequiredArgs::T0RequiredArgs>(char const *,char const *,int,struct RequiredArgs::T0RequiredArgs const &)" (??0?$TDecl@VSOverlay@@UT0RequiredArgs@RequiredArgs@@@@QEAA@PEBD0HAEBUT0RequiredArgs@RequiredArgs@@@Z)
1>MyUIWidget.cpp.obj : error LNK2019: unresolved external symbol "__declspec(dllimport) public: void __cdecl STextBlock::Construct(struct STextBlock::FArguments const &)" (__imp_?Construct@STextBlock@@QEAAXAEBUFArguments@1@@Z) referenced in function "public: void __cdecl RequiredArgs::T0RequiredArgs::CallConstruct<class STextBlock,struct STextBlock::FArguments>(class TSharedRef<class STextBlock,0> const &,struct STextBlock::FArguments const &)const " (??$CallConstruct@VSTextBlock@@UFArguments@1@@T0RequiredArgs@RequiredArgs@@QEBAXAEBV?$TSharedRef@VSTextBlock@@$0A@@@AEBUFArguments@STextBlock@@@Z)
1>MyUIWidget.cpp.obj : error LNK2019: unresolved external symbol "__declspec(dllimport) public: __cdecl STextBlock::STextBlock(void)" (__imp_??0STextBlock@@QEAA@XZ) referenced in function "public: __cdecl TDecl<class STextBlock,struct RequiredArgs::T0RequiredArgs>::TDecl<class STextBlock,struct RequiredArgs::T0RequiredArgs>(char const *,char const *,int,struct RequiredArgs::T0RequiredArgs const &)" (??0?$TDecl@VSTextBlock@@UT0RequiredArgs@RequiredArgs@@@@QEAA@PEBD0HAEBUT0RequiredArgs@RequiredArgs@@@Z)
1>MyUIWidget.cpp.obj : error LNK2019: unresolved external symbol "__declspec(dllimport) public: virtual __cdecl STextBlock::~STextBlock(void)" (__imp_??1STextBlock@@UEAA@XZ) referenced in function "public: virtual void * __cdecl STextBlock::`scalar deleting destructor'(unsigned int)" (??_GSTextBlock@@UEAAPEAXI@Z)
1>MyUIWidget.cpp.obj : error LNK2001: unresolved external symbol "public: virtual void __cdecl SLeafWidget::ArrangeChildren(class FGeometry const &,class FArrangedChildren &)const " (?ArrangeChildren@SLeafWidget@@UEBAXAEBVFGeometry@@AEAVFArrangedChildren@@@Z)
1>MyUIWidget.cpp.obj : error LNK2001: unresolved external symbol "public: virtual void __cdecl SOverlay::ArrangeChildren(class FGeometry const &,class FArrangedChildren &)const " (?ArrangeChildren@SOverlay@@UEBAXAEBVFGeometry@@AEAVFArrangedChildren@@@Z)
1>MyUIWidget.cpp.obj : error LNK2001: unresolved external symbol "public: virtual void __cdecl STextBlock::CacheDesiredSize(void)" (?CacheDesiredSize@STextBlock@@UEAAXXZ)
1>MyUIWidget.cpp.obj : error LNK2001: unresolved external symbol "protected: virtual void __cdecl SWidget::CacheDesiredSize(void)" (?CacheDesiredSize@SWidget@@MEAAXXZ)
1>MyUIWidget.cpp.obj : error LNK2001: unresolved external symbol "public: virtual struct FVector2D __cdecl SOverlay::ComputeDesiredSize(void)const " (?ComputeDesiredSize@SOverlay@@UEBA?AUFVector2D@@XZ)
1>MyUIWidget.cpp.obj : error LNK2001: unresolved external symbol "public: virtual struct FVector2D __cdecl STextBlock::ComputeDesiredSize(void)const " (?ComputeDesiredSize@STextBlock@@UEBA?AUFVector2D@@XZ)
1>MyUIWidget.cpp.obj : error LNK2001: unresolved external symbol "public: virtual class FChildren * __cdecl SLeafWidget::GetChildren(void)" (?GetChildren@SLeafWidget@@UEAAPEAVFChildren@@XZ)
1>MyUIWidget.cpp.obj : error LNK2001: unresolved external symbol "public: virtual class FChildren * __cdecl SOverlay::GetChildren(void)" (?GetChildren@SOverlay@@UEAAPEAVFChildren@@XZ)
1>MyUIWidget.cpp.obj : error LNK2001: unresolved external symbol "public: virtual struct FSlateColor __cdecl SWidget::GetForegroundColor(void)const " (?GetForegroundColor@SWidget@@UEBA?AUFSlateColor@@XZ)
1>MyUIWidget.cpp.obj : error LNK2001: unresolved external symbol "public: virtual class FString __cdecl SWidget::GetParsableFileAndLineNumber(void)const " (?GetParsableFileAndLineNumber@SWidget@@UEBA?AVFString@@XZ)
1>MyUIWidget.cpp.obj : error LNK2001: unresolved external symbol "public: virtual class FString __cdecl SWidget::GetReadableLocation(void)const " (?GetReadableLocation@SWidget@@UEBA?AVFString@@XZ)
1>MyUIWidget.cpp.obj : error LNK2001: unresolved external symbol "public: virtual class TSharedPtr<class SToolTip,0> __cdecl SWidget::GetToolTip(void)" (?GetToolTip@SWidget@@UEAA?AV?$TSharedPtr@VSToolTip@@$0A@@@XZ)
1>MyUIWidget.cpp.obj : error LNK2001: unresolved external symbol "public: virtual enum EWindowZone::Type __cdecl SWidget::GetWindowZoneOverride(void)const " (?GetWindowZoneOverride@SWidget@@UEBA?AW4Type@EWindowZone@@XZ)
1>MyUIWidget.cpp.obj : error LNK2001: unresolved external symbol "public: virtual bool __cdecl SWidget::HasKeyboardFocus(void)const " (?HasKeyboardFocus@SWidget@@UEBA_NXZ)
1>MyUIWidget.cpp.obj : error LNK2001: unresolved external symbol "public: virtual bool __cdecl SWidget::IsHovered(void)const " (?IsHovered@SWidget@@UEBA_NXZ)
1>MyUIWidget.cpp.obj : error LNK2001: unresolved external symbol "public: virtual class FReply __cdecl SWidget::OnControllerAnalogValueChanged(class FGeometry const &,class FControllerEvent const &)" (?OnControllerAnalogValueChanged@SWidget@@UEAA?AVFReply@@AEBVFGeometry@@AEBVFControllerEvent@@@Z)
1>MyUIWidget.cpp.obj : error LNK2001: unresolved external symbol "public: virtual class FReply __cdecl SWidget::OnControllerButtonPressed(class FGeometry const &,class FControllerEvent const &)" (?OnControllerButtonPressed@SWidget@@UEAA?AVFReply@@AEBVFGeometry@@AEBVFControllerEvent@@@Z)
1>MyUIWidget.cpp.obj : error LNK2001: unresolved external symbol "public: virtual class FReply __cdecl SWidget::OnControllerButtonReleased(class FGeometry const &,class FControllerEvent const &)" (?OnControllerButtonReleased@SWidget@@UEAA?AVFReply@@AEBVFGeometry@@AEBVFControllerEvent@@@Z)
1>MyUIWidget.cpp.obj : error LNK2001: unresolved external symbol "public: virtual class FCursorReply __cdecl SWidget::OnCursorQuery(class FGeometry const &,class FPointerEvent const &)const " (?OnCursorQuery@SWidget@@UEBA?AVFCursorReply@@AEBVFGeometry@@AEBVFPointerEvent@@@Z)
1>MyUIWidget.cpp.obj : error LNK2001: unresolved external symbol "public: virtual class FReply __cdecl SWidget::OnDragDetected(class FGeometry const &,class FPointerEvent const &)" (?OnDragDetected@SWidget@@UEAA?AVFReply@@AEBVFGeometry@@AEBVFPointerEvent@@@Z)
1>MyUIWidget.cpp.obj : error LNK2001: unresolved external symbol "public: virtual void __cdecl SWidget::OnDragEnter(class FGeometry const &,class FDragDropEvent const &)" (?OnDragEnter@SWidget@@UEAAXAEBVFGeometry@@AEBVFDragDropEvent@@@Z)
1>MyUIWidget.cpp.obj : error LNK2001: unresolved external symbol "public: virtual void __cdecl SWidget::OnDragLeave(class FDragDropEvent const &)" (?OnDragLeave@SWidget@@UEAAXAEBVFDragDropEvent@@@Z)
1>MyUIWidget.cpp.obj : error LNK2001: unresolved external symbol "public: virtual class FReply __cdecl SWidget::OnDragOver(class FGeometry const &,class FDragDropEvent const &)" (?OnDragOver@SWidget@@UEAA?AVFReply@@AEBVFGeometry@@AEBVFDragDropEvent@@@Z)
1>MyUIWidget.cpp.obj : error LNK2001: unresolved external symbol "public: virtual class FReply __cdecl SWidget::OnDrop(class FGeometry const &,class FDragDropEvent const &)" (?OnDrop@SWidget@@UEAA?AVFReply@@AEBVFGeometry@@AEBVFDragDropEvent@@@Z)
1>MyUIWidget.cpp.obj : error LNK2001: unresolved external symbol "public: virtual bool __cdecl SWidget::OnHitTest(class FGeometry const &,struct FVector2D)" (?OnHitTest@SWidget@@UEAA_NAEBVFGeometry@@UFVector2D@@@Z)
1>MyUIWidget.cpp.obj : error LNK2001: unresolved external symbol "public: virtual class FReply __cdecl SWidget::OnKeyChar(class FGeometry const &,class FCharacterEvent const &)" (?OnKeyChar@SWidget@@UEAA?AVFReply@@AEBVFGeometry@@AEBVFCharacterEvent@@@Z)
1>MyUIWidget.cpp.obj : error LNK2001: unresolved external symbol "public: virtual class FReply __cdecl SWidget::OnKeyDown(class FGeometry const &,class FKeyboardEvent const &)" (?OnKeyDown@SWidget@@UEAA?AVFReply@@AEBVFGeometry@@AEBVFKeyboardEvent@@@Z)
1>MyUIWidget.cpp.obj : error LNK2001: unresolved external symbol "public: virtual class FReply __cdecl SWidget::OnKeyUp(class FGeometry const &,class FKeyboardEvent const &)" (?OnKeyUp@SWidget@@UEAA?AVFReply@@AEBVFGeometry@@AEBVFKeyboardEvent@@@Z)
1>MyUIWidget.cpp.obj : error LNK2001: unresolved external symbol "public: virtual void __cdecl SWidget::OnKeyboardFocusChanging(class FWeakWidgetPath const &,class FWidgetPath const &)" (?OnKeyboardFocusChanging@SWidget@@UEAAXAEBVFWeakWidgetPath@@AEBVFWidgetPath@@@Z)
1>MyUIWidget.cpp.obj : error LNK2001: unresolved external symbol "public: virtual void __cdecl SWidget::OnKeyboardFocusLost(class FKeyboardFocusEvent const &)" (?OnKeyboardFocusLost@SWidget@@UEAAXAEBVFKeyboardFocusEvent@@@Z)
1>MyUIWidget.cpp.obj : error LNK2001: unresolved external symbol "public: virtual class FReply __cdecl SWidget::OnKeyboardFocusReceived(class FGeometry const &,class FKeyboardFocusEvent const &)" (?OnKeyboardFocusReceived@SWidget@@UEAA?AVFReply@@AEBVFGeometry@@AEBVFKeyboardFocusEvent@@@Z)
1>MyUIWidget.cpp.obj : error LNK2001: unresolved external symbol "public: virtual class FReply __cdecl SWidget::OnMotionDetected(class FGeometry const &,class FMotionEvent const &)" (?OnMotionDetected@SWidget@@UEAA?AVFReply@@AEBVFGeometry@@AEBVFMotionEvent@@@Z)
1>MyUIWidget.cpp.obj : error LNK2001: unresolved external symbol "public: virtual class FReply __cdecl STextBlock::OnMouseButtonDoubleClick(class FGeometry const &,class FPointerEvent const &)" (?OnMouseButtonDoubleClick@STextBlock@@UEAA?AVFReply@@AEBVFGeometry@@AEBVFPointerEvent@@@Z)
1>MyUIWidget.cpp.obj : error LNK2001: unresolved external symbol "public: virtual class FReply __cdecl SWidget::OnMouseButtonDoubleClick(class FGeometry const &,class FPointerEvent const &)" (?OnMouseButtonDoubleClick@SWidget@@UEAA?AVFReply@@AEBVFGeometry@@AEBVFPointerEvent@@@Z)
1>MyUIWidget.cpp.obj : error LNK2001: unresolved external symbol "public: virtual class FReply __cdecl SWidget::OnMouseButtonDown(class FGeometry const &,class FPointerEvent const &)" (?OnMouseButtonDown@SWidget@@UEAA?AVFReply@@AEBVFGeometry@@AEBVFPointerEvent@@@Z)
1>MyUIWidget.cpp.obj : error LNK2001: unresolved external symbol "public: virtual class FReply __cdecl SWidget::OnMouseButtonUp(class FGeometry const &,class FPointerEvent const &)" (?OnMouseButtonUp@SWidget@@UEAA?AVFReply@@AEBVFGeometry@@AEBVFPointerEvent@@@Z)
1>MyUIWidget.cpp.obj : error LNK2001: unresolved external symbol "public: virtual void __cdecl SWidget::OnMouseCaptureLost(void)" (?OnMouseCaptureLost@SWidget@@UEAAXXZ)
1>MyUIWidget.cpp.obj : error LNK2001: unresolved external symbol "public: virtual void __cdecl SWidget::OnMouseEnter(class FGeometry const &,class FPointerEvent const &)" (?OnMouseEnter@SWidget@@UEAAXAEBVFGeometry@@AEBVFPointerEvent@@@Z)
1>MyUIWidget.cpp.obj : error LNK2001: unresolved external symbol "public: virtual void __cdecl SWidget::OnMouseLeave(class FPointerEvent const &)" (?OnMouseLeave@SWidget@@UEAAXAEBVFPointerEvent@@@Z)
1>MyUIWidget.cpp.obj : error LNK2001: unresolved external symbol "public: virtual class FReply __cdecl SWidget::OnMouseMove(class FGeometry const &,class FPointerEvent const &)" (?OnMouseMove@SWidget@@UEAA?AVFReply@@AEBVFGeometry@@AEBVFPointerEvent@@@Z)
1>MyUIWidget.cpp.obj : error LNK2001: unresolved external symbol "public: virtual class FReply __cdecl SWidget::OnMouseWheel(class FGeometry const &,class FPointerEvent const &)" (?OnMouseWheel@SWidget@@UEAA?AVFReply@@AEBVFGeometry@@AEBVFPointerEvent@@@Z)
1>MyUIWidget.cpp.obj : error LNK2001: unresolved external symbol "public: virtual int __cdecl SOverlay::OnPaint(class FGeometry const &,class FSlateRect const &,class FSlateWindowElementList &,int,class FWidgetStyle const &,bool)const " (?OnPaint@SOverlay@@UEBAHAEBVFGeometry@@AEBVFSlateRect@@AEAVFSlateWindowElementList@@HAEBVFWidgetStyle@@_N@Z)
1>MyUIWidget.cpp.obj : error LNK2001: unresolved external symbol "public: virtual int __cdecl STextBlock::OnPaint(class FGeometry const &,class FSlateRect const &,class FSlateWindowElementList &,int,class FWidgetStyle const &,bool)const " (?OnPaint@STextBlock@@UEBAHAEBVFGeometry@@AEBVFSlateRect@@AEAVFSlateWindowElementList@@HAEBVFWidgetStyle@@_N@Z)
1>MyUIWidget.cpp.obj : error LNK2001: unresolved external symbol "public: virtual class FReply __cdecl SWidget::OnPreviewKeyDown(class FGeometry const &,class FKeyboardEvent const &)" (?OnPreviewKeyDown@SWidget@@UEAA?AVFReply@@AEBVFGeometry@@AEBVFKeyboardEvent@@@Z)
1>MyUIWidget.cpp.obj : error LNK2001: unresolved external symbol "public: virtual class FReply __cdecl SWidget::OnPreviewMouseButtonDown(class FGeometry const &,class FPointerEvent const &)" (?OnPreviewMouseButtonDown@SWidget@@UEAA?AVFReply@@AEBVFGeometry@@AEBVFPointerEvent@@@Z)
1>MyUIWidget.cpp.obj : error LNK2001: unresolved external symbol "public: virtual void __cdecl SWidget::OnToolTipClosing(void)" (?OnToolTipClosing@SWidget@@UEAAXXZ)
1>MyUIWidget.cpp.obj : error LNK2001: unresolved external symbol "public: virtual class FReply __cdecl SWidget::OnTouchEnded(class FGeometry const &,class FPointerEvent const &)" (?OnTouchEnded@SWidget@@UEAA?AVFReply@@AEBVFGeometry@@AEBVFPointerEvent@@@Z)
1>MyUIWidget.cpp.obj : error LNK2001: unresolved external symbol "public: virtual class FReply __cdecl SWidget::OnTouchGesture(class FGeometry const &,class FPointerEvent const &)" (?OnTouchGesture@SWidget@@UEAA?AVFReply@@AEBVFGeometry@@AEBVFPointerEvent@@@Z)
1>MyUIWidget.cpp.obj : error LNK2001: unresolved external symbol "public: virtual class FReply __cdecl SWidget::OnTouchMoved(class FGeometry const &,class FPointerEvent const &)" (?OnTouchMoved@SWidget@@UEAA?AVFReply@@AEBVFGeometry@@AEBVFPointerEvent@@@Z)
1>MyUIWidget.cpp.obj : error LNK2001: unresolved external symbol "public: virtual class FReply __cdecl SWidget::OnTouchStarted(class FGeometry const &,class FPointerEvent const &)" (?OnTouchStarted@SWidget@@UEAA?AVFReply@@AEBVFGeometry@@AEBVFPointerEvent@@@Z)
1>MyUIWidget.cpp.obj : error LNK2001: unresolved external symbol "public: virtual bool __cdecl SWidget::OnVisualizeTooltip(class TSharedPtr<class SWidget,0> const &)" (?OnVisualizeTooltip@SWidget@@UEAA_NAEBV?$TSharedPtr@VSWidget@@$0A@@@@Z)
1>MyUIWidget.cpp.obj : error LNK2001: unresolved external symbol "public: virtual bool __cdecl SWidget::SupportsKeyboardFocus(void)const " (?SupportsKeyboardFocus@SWidget@@UEBA_NXZ)
1>MyUIWidget.cpp.obj : error LNK2001: unresolved external symbol "public: virtual void __cdecl SWidget::Tick(class FGeometry const &,double,float)" (?Tick@SWidget@@UEAAXAEBVFGeometry@@NM@Z)
1>MyUIWidget.cpp.obj : error LNK2001: unresolved external symbol "public: virtual class FString __cdecl SWidget::ToString(void)const " (?ToString@SWidget@@UEBA?AVFString@@XZ)
1>MyUIWidget.cpp.obj : error LNK2001: unresolved external symbol "__declspec(dllimport) public: static struct EVisibility const EVisibility::Visible" (__imp_?Visible@EVisibility@@2U1@B)
1>MyUIWidget.cpp.obj : error LNK2001: unresolved external symbol "__declspec(dllimport) public: static struct EVisibility const EVisibility::SelfHitTestInvisible" (__imp_?SelfHitTestInvisible@EVisibility@@2U1@B)
1>MyUIWidget.cpp.obj : error LNK2001: unresolved external symbol "__declspec(dllimport) public: static class FName const FTextBlockStyle::TypeName" (__imp_?TypeName@FTextBlockStyle@@2VFName@@B)
1>C:\Users\Trae\Documents\Unreal Projects\MyProject\Binaries\Win64\UE4Editor-MyProject.dll : fatal error LNK1120: 76 unresolved externals

Are you linking to Slate in your project dependencies?

looks like you need to add Slate as a build dependency in your games build.cs file

Have a look in MyProject/Source/MyProject/MyProject.Build.cs and add slate here.

Is this not a default setting?

No, not all projects will use Slate so it’s optional. The correct code should be present, but commented out, in your .Build.cs file.

doesn’t appear to be.
Seems like the only dependencies are

PublicDependencyModuleNames.AddRange(new string[] { “Core”, “CoreUObject”, “Engine”, “InputCore” });

if you have a dependency in private code, note the folder your source file resides, Then you’ll want to add:

PrivateDependencyModuleNames.Add(“Slate”);

MyProject\Source\MyProject\MyProject.Build.cs

I see it there, got it.

There should really be a sticky on the forums.

Actually, I just created a sample code project and found this in the Build.cs

	// Uncomment if you are using Slate UI
	// PrivateDependencyModuleNames.Add("Slate");

Uncommenting should sort you out.

Terence

Well, I just built “Hello, World!” with a text-box.

So, I hear I can’t see the UI from within the Editor Viewport, I’ll have to launch a game, correct?

That’s correct.

You must use “Play in new window” option insted play in viewport to view Slate

And “Hello, Slate World!” has been built and is 100% working! I’ll be releasing a tutorial on the forums, I’ll be sure to mention you all and everyone else involved.

If your using Unreal engine 4.3 and the other answers doesn’t work for you,

Try using the following
PrivateDependencyModuleNames.AddRange(new string[] { “Slate”, “SlateCore” });

instead of
PrivateDependencyModuleNames.Add(“Slate”);