Unreal Engine Issues and Bug Tracker (UE-37029)

Description

Editing property with InlineEditConditionToggle meta specifier causes the editor to crash.

Workaround:
Calling Super::PostEditChangeProperty after property changing code prevents crash from occurring.

Steps to Reproduce

Open UE4 Editor (any project)
Add code to project based on Actor Component (MyActorComp)
Add include statement for Engine.h to MyActorComp.h include list

Add following struct between include list and UCLASS() macro

USTRUCT()
struct FTestStruct
{
	GENERATED_BODY()

		UPROPERTY(EditAnywhere)
		int32 Prop;

	UPROPERTY(EditAnywhere, Meta = (InlineEditConditionToggle))
		bool bEditConditionProp;

	UPROPERTY(EditAnywhere, Meta = (EditCondition = bEditConditionProp))
		int32 OtherProp;
};

Add following code to class declaration:

#if WITH_EDITOR
	virtual void PostEditChangeProperty(FPropertyChangedEvent& PropertyChangedEvent) override
	{
		Super::PostEditChangeProperty(PropertyChangedEvent);
		for (FTestStruct& TestStruct : TestArray)
		{
			TestStruct.Prop = 1;
		}
	}
#endif

	UPROPERTY(EditAnywhere)
		TArray<FTestStruct> TestArray;

Compile
Add blueprint based on Actor (ActorBP)
Add MyActorComp component to ActorBP
Set number of elements of TestArray to two
Click the checkbox for "OtherProp" of element two

Result:
The editor crashes with listed callstack

Expected:
Checkbox is updated and editor continues to run

Callstack

MachineId:7156C35640F86204E61B8383F45DEE17
EpicAccountId:c807849e05a0413d99e379f2802cae9c

Assertion failed: ContainerPtr [File:D:\Build\++UE4+Release-4.13+Compile\Sync\Engine\Source\Runtime\CoreUObject\Public\UObject\UnrealType.h] [Line: 303] 



UE4Editor_Core!FDebug::AssertFailed() [d:\build\++ue4+release-4.13+compile\sync\engine\source\runtime\core\private\misc\outputdevice.cpp:421]
UE4Editor_PropertyEditor!FPropertyEditor::SetEditConditionState() [d:\build\++ue4+release-4.13+compile\sync\engine\source\editor\propertyeditor\private\presentation\propertyeditor\propertyeditor.cpp:385]
UE4Editor_PropertyEditor!TBaseSPMethodDelegateInstance<0,SEditConditionWidget,0,TTypeWrapper<void> __cdecl(enum ECheckBoxState)>::Execute() [d:\build\++ue4+release-4.13+compile\sync\engine\source\runtime\core\public\delegates\delegateinstancesimpl.h:317]
UE4Editor_PropertyEditor!TBaseSPMethodDelegateInstance<0,SEditConditionWidget,0,void __cdecl(enum ECheckBoxState)>::ExecuteIfSafe() [d:\build\++ue4+release-4.13+compile\sync\engine\source\runtime\core\public\delegates\delegateinstancesimpl.h:424]
UE4Editor_Slate!SCheckBox::ToggleCheckedState() [d:\build\++ue4+release-4.13+compile\sync\engine\source\runtime\slate\private\widgets\input\scheckbox.cpp:293]
UE4Editor_Slate!SCheckBox::OnMouseButtonUp() [d:\build\++ue4+release-4.13+compile\sync\engine\source\runtime\slate\private\widgets\input\scheckbox.cpp:184]
UE4Editor_Slate!<lambda_8d0e9a1da76abd0a756a3a9d775f5ed1>::operator()() [d:\build\++ue4+release-4.13+compile\sync\engine\source\runtime\slate\private\framework\application\slateapplication.cpp:4901]
UE4Editor_Slate!FEventRouter::Route<FReply,FEventRouter::FToLeafmostPolicy,FPointerEvent,<lambda_8d0e9a1da76abd0a756a3a9d775f5ed1> >() [d:\build\++ue4+release-4.13+compile\sync\engine\source\runtime\slate\private\framework\application\slateapplication.cpp:215]
UE4Editor_Slate!FSlateApplication::RoutePointerUpEvent() [d:\build\++ue4+release-4.13+compile\sync\engine\source\runtime\slate\private\framework\application\slateapplication.cpp:4890]
UE4Editor_Slate!FSlateApplication::ProcessMouseButtonUpEvent() [d:\build\++ue4+release-4.13+compile\sync\engine\source\runtime\slate\private\framework\application\slateapplication.cpp:5348]
UE4Editor_Slate!FSlateApplication::OnMouseUp() [d:\build\++ue4+release-4.13+compile\sync\engine\source\runtime\slate\private\framework\application\slateapplication.cpp:5328]
UE4Editor_Core!FWindowsApplication::ProcessDeferredMessage() [d:\build\++ue4+release-4.13+compile\sync\engine\source\runtime\core\private\windows\windowsapplication.cpp:1584]
UE4Editor_Core!FWindowsApplication::DeferMessage() [d:\build\++ue4+release-4.13+compile\sync\engine\source\runtime\core\private\windows\windowsapplication.cpp:1930]
UE4Editor_Core!FWindowsApplication::ProcessMessage() [d:\build\++ue4+release-4.13+compile\sync\engine\source\runtime\core\private\windows\windowsapplication.cpp:747]
UE4Editor_Core!FWindowsApplication::AppWndProc() [d:\build\++ue4+release-4.13+compile\sync\engine\source\runtime\core\private\windows\windowsapplication.cpp:669]
user32
user32
UE4Editor_Core!FWindowsPlatformMisc::PumpMessages() [d:\build\++ue4+release-4.13+compile\sync\engine\source\runtime\core\private\windows\windowsplatformmisc.cpp:905]
UE4Editor!FEngineLoop::Tick() [d:\build\++ue4+release-4.13+compile\sync\engine\source\runtime\launch\private\launchengineloop.cpp:2788]
UE4Editor!GuardedMain() [d:\build\++ue4+release-4.13+compile\sync\engine\source\runtime\launch\private\launch.cpp:156]
UE4Editor!GuardedMainWrapper() [d:\build\++ue4+release-4.13+compile\sync\engine\source\runtime\launch\private\windows\launchwindows.cpp:126]
UE4Editor!WinMain() [d:\build\++ue4+release-4.13+compile\sync\engine\source\runtime\launch\private\windows\launchwindows.cpp:202]
UE4Editor!__scrt_common_main_seh() [f:\dd\vctools\crt\vcstartup\src\startup\exe_common.inl:264]
kernel32
ntdll

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Fixed

Component	Tools
Affects Versions	4.13.1
Target Fix	4.14

Fix Commit	3164775
Release Commit	3164775

Created	Oct 7, 2016
Resolved	Oct 17, 2016
Updated	Feb 4, 2019

UE-37029

Editing InlineEditConditionToggle variable value causes editor to crash

Editing InlineEditConditionToggle variable value causes editor to crash

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