[UE5.4] [PropertyEditor] How to get property handle from IDetailLayoutBuilder?

Development Programming & Scripting
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1

I am trying to customize the detail view of the UObject with IDetailCustomization.

Here is the code

UCLASS()
class DETAILVIEW_TEST_API UMyDataAsset : public UDataAsset
{
	GENERATED_BODY()
public:
	UPROPERTY()
	int Num1;

	UPROPERTY(meta = (ClampMin = "0", ClampMax = "100"))
	int Num2;
};

/**
* Customize the details view for UMyDataAsset
*/
class DETAILVIEW_TEST_API FMyDataAssetDetails : public IDetailCustomization {
public:
	void CustomizeDetails(IDetailLayoutBuilder& builder) override {
		IDetailCategoryBuilder& Setting = builder.EditCategory("Setting");
		
		// If setup properly, there will be a new row in details view. 
		Setting.AddCustomRow(FText::FromString("Test"))
		.NameContent()
		[
			SNew(STextBlock)
			.Text(FText::FromString("Test"))
			.Font(builder.GetDetailFont())
		];

		// Try to get property and show it
		TSharedPtr<IPropertyHandle> Num1_Handle = builder.GetProperty(GET_MEMBER_NAME_CHECKED(UMyDataAsset, Num1));
		if (Num1_Handle->IsValidHandle())
			Setting.AddProperty(Num1_Handle);
		else
			UE_LOG(LogTemp, Warning, TEXT("Cannot find property Num1"));

		TSharedPtr<IPropertyHandle> Num2_Handle = builder.GetProperty(GET_MEMBER_NAME_CHECKED(UMyDataAsset, Num2));
		if (Num2_Handle->IsValidHandle())
			Setting.AddProperty(Num2_Handle);
		else
			UE_LOG(LogTemp, Warning, TEXT("Cannot find property Num2"));
	}

	static TSharedRef<IDetailCustomization> CreateInstance() {
		return MakeShared<FMyDataAssetDetails>();
	}
};

I also register FMyDataAssetDetails, when the module start up.

void MyGameModule::StartupModule()
{
	FPropertyEditorModule& M = FModuleManager::Get().LoadModuleChecked<FPropertyEditorModule>("PropertyEditor");

	M.RegisterCustomClassLayout(UMyDataAsset::StaticClass()->GetFName(),
		FOnGetDetailCustomizationInstance::CreateStatic( FMyDataAssetDetails::CreateInstance ));
}

void MyGameModule::ShutdownModule()
{
	FPropertyEditorModule& M = FModuleManager::Get().LoadModuleChecked<FPropertyEditorModule>("PropertyEditor");

	M.UnregisterCustomClassLayout(UMyDataAsset::StaticClass()->GetFName());
}

The result:

image
image1009×588 24.3 KB

image

This is not what I am expecting. FMyDataAssetDetails ::CustomizeDetails is called, but I cannot get property handle from IDetailLayoutBuilder.

Does anyone know how to solve it?

2

After a few hours of try, I finally know what’s going wrong.

It seems that IDetailLayoutBuilder::GetProperty can only get the property handle of the property that will be shown in Detail View by default.

Therefore, EditAnywhere, VisibleAnywhere, or something like that should appear inside UPROPERTY().

After revision:

UCLASS()
class DETAILVIEW_TEST_API UMyDataAsset : public UDataAsset
{
	GENERATED_BODY()
public:
	UPROPERTY(EditAnywhere)
	int Num1;

	UPROPERTY(EditAnywhere, meta = (ClampMin = "0", ClampMax = "100"))
	int Num2;
};