How do I set keyboard focus on SButton?

Development Programming & Scripting UI
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1

I have tried my best to figure this out but my lack of experience with slate and my inability to find related questions or forum posts has left me needing help. The best learning resource I found was Reuben Wards youtube tutorial on designing a UI using slate. I have also gone though all related header files and available Unreal Documentation.

My UI looks and works exactly as intended after writing it in slate, and I understand what the code is doing. I just don’t know how to manually set focus on a SButton either at creation or when a button is pressed on either keyboard or gamepad with slate, something I can do with UButton in c++ with no issue.

I can see that in SWidget there is a boolean bIsHovered but I don’t know how to access the SButton after creating it in the ChildSlot. Here’s my not working attempt.

	ChildSlot
        [
            SNew(SOverlay)
            + SOverlay::Slot()
            .HAlign(HAlign_Fill)
            .VAlign(VAlign_Fill)
            [
                SNew(SConstraintCanvas)
                + SConstraintCanvas::Slot()
                .Anchors(FAnchors(0.05f, 0.05f, .9f, .35f))
                .AutoSize(true)
                .Alignment(FVector2D(5.f,.5f))
                [
                    SNew(SScaleBox)
                    .HAlign(HAlign_Center)
                    .VAlign(VAlign_Center)
                    .Stretch(EStretch::ScaleToFill)
                    [
                        SNew(STextBlock)
                        .ColorAndOpacity(FColor::White)
                        .Font(TitleTextStyle)
                        .Margin(FMargin(12.f))
                        .Text(TitleText)
                        .Justification(ETextJustify::Left)
                    ]
                ]
                // PlayButton
                + SConstraintCanvas::Slot()
                .Anchors(FAnchors(.1f, .4f, .3f, .55f))
                [
                    SNew(SScaleBox)
                    .HAlign(HAlign_Fill)
                    .VAlign(VAlign_Fill)
                    .Stretch(EStretch::ScaleToFit)
                    [
                        SNew(SButton)
                        .ButtonColorAndOpacity(Transparency)
                        .OnClicked(this, &SMainMenuWidget::OnPlayClicked)
                        [
                            SNew(STextBlock)
                            .ColorAndOpacity(FLinearColor(1,1,1,1))
                            .Font(ButtonTextStyle)
                            .Text(PlayText)
                            .Justification(ETextJustify::Left)
                        ]
                    ]
                ]
            ];

        TSharedPtr<SWidget, ESPMode::NotThreadSafe> ActiveButton = ChildSlot.GetChildAt(2);
        UWidget* ActiveWidget = Cast<UWidget>(ActiveButton.Get());
        if(!ActiveWidget){UE_LOG(LogTemp, Error, TEXT("ActiveWidget Cast Failed!!")); return;}
        ActiveWidget->SetFocus();

Removing the last 4 lines results in a successful compile. If more of my code is needed please let me know, I just didn’t want to make this too long as I’m sure that someone that knows slate will have no issue explaining how to do this.

If anyone can show me how to make a SButton hovered by code I would greatly appreciate it!

2

I have modified the code to make accessing the buttons easier. I still don’t know what to do with them though.

Widget.h

	TSharedPtr<SButton> PlayButton;
	TSharedPtr<SButton> SettingsButton;
	TSharedPtr<SButton> CustomiseButton;
	TSharedPtr<SButton> QuitButton;

Widget.cpp

	ChildSlot
        [
            SNew(SOverlay) ......
            ....// PlayButton
                + SConstraintCanvas::Slot()
                .Anchors(FAnchors(.1f, .4f, .3f, .55f))
                [
                    SNew(SScaleBox)
                    .HAlign(HAlign_Fill)
                    .VAlign(VAlign_Fill)
                    .Stretch(EStretch::ScaleToFit)
                    [
                        SAssignNew(PlayButton, SButton)
                        .ButtonColorAndOpacity(Transparency)
                        .OnClicked(this, &SMainMenuWidget::OnPlayClicked)
                        [
                            SNew(STextBlock)
                            .ColorAndOpacity(FLinearColor(1,1,1,1))
                            .Font(ButtonTextStyle)
                            .Text(PlayText)
                            .Justification(ETextJustify::Left)
                        ]
                    ]
                ]    
        ....
    ]
3

In the header file have publicly declared

virtual bool IsInteractable() const override {return true;};
virtual bool SupportsKeyboardFocus() const override { return true;};

TSharedPtr<SButton> ButtonToFocusOn;

Implement as follows in slate code (see my comment)

SAssignNew(ButtonToFocusOn, SButton)

When creating the widget containing the button save a reference to it, then set focus as follows (modify as required) I have this in my MenuHUD.cpp

FSlateApplication::Get().SetKeyboardFocus(WidgetReference->ButtonToFocusOn.ToSharedRef());

If includes are correct this should work. (Thanks to BrUnO_XaVIeR How do I set focus on SButton - #6 by CanadianCheesus)