How are Tick functions for slate widgets written?

[lazyFrond]

I’m attempting to write a Tick function for a slate widget. Will you provide an example of an operational tick function within a slate widget?

[lazyFrond]

why yes it just so happens I can! Follow the example exactly, any misspelling or omissions will cause the code to error.
.h file:

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

	SLATE_ARGUMENT(TWeakObjectPtr<class ATestHud>, OwningHUD)

	SLATE_ARGUMENT(APlayerController*, playerOnePlayerController)

	SLATE_END_ARGS()

	/** Constructs this widget with InArgs */
	void Construct(const FArguments& InArgs);
	
	void Tick(const FGeometry& AllottedGeometry, const double InCurrentTime, const float InDeltaTime);

    //...
};

.cpp file:

void SLoadingScreenOne::Construct(const FArguments& InArgs)
{
	SetCanTick(true);
	bCanSupportFocus = true;

	OwningHUD = InArgs._OwningHUD;
	playerOnePlayerController = InArgs._playerOnePlayerController;
    //...
}

void SLoadingScreenOne::Tick(const FGeometry& AllottedGeometry, const double InCurrentTime, const float InDeltaTime)
{
	SCompoundWidget::Tick(AllottedGeometry, InCurrentTime, InDeltaTime);

	//.. your tick code here
}

I got the player controller in my hud class and passed it into the widget on creation.

[3dRaven]

Don’t forget to implement ReleaseSlateResources for your userwidget wrapper or you will get a memory leak.

[lazyFrond]

hwhat
I couldn’t find any specific ReleaseSlateResources function or class. could you link me into a documentation

[3dRaven]

You need to release the slate resource from within the widget.

Take a look at the progress bar engine implementation as an example. The engine will warn you about the memory leak if you add your wiget to a canvas

Outer Widget that uses the custom slate:

.h

#pragma once

#include "CoreMinimal.h"
#include "Blueprint/UserWidget.h"
#include "WLoadingScreenOne.generated.h"

class SLoadingScreenOne;
/**
 * 
 */
UCLASS()
class MYPROJECT_API UWLoadingScreenOne : public UUserWidget
{
	GENERATED_BODY()
	
public:
	virtual void ReleaseSlateResources(bool bReleaseChildren) override;

protected:
	/** Native Slate Widget */
	TSharedPtr<SLoadingScreenOne> MyLoadingScreen;

	virtual TSharedRef<SWidget> RebuildWidget() override;

};

.cpp

#include "WLoadingScreenOne.h"
#include "SLoadingScreenOne.h"

TSharedRef<SWidget> UWLoadingScreenOne::RebuildWidget()
{
	MyLoadingScreen = SNew(SLoadingScreenOne);

	return MyLoadingScreen.ToSharedRef();
}

void UWLoadingScreenOne::ReleaseSlateResources(bool bReleaseChildren)
{
	Super::ReleaseSlateResources(bReleaseChildren);

	MyLoadingScreen.Reset();
}

[lazyFrond]

thank you for mentioning this! My widget code inherits from SWidget, which does not contain a ReleaseSlateResources function nor a RebuildWidget function. I have to imagine releasingSlateResources is a non issue for descendents of SWidget, but I do have my functional Swidgets nested in blank Swidgets when adding to and removing from viewport.

Thank you for saying something I’ll keep an eye out

[3dRaven]

It’ll come in handy if you decide to put it inside of a UserWidget in the future