Create widget and add to viewport for HUD

Pattern: BeginPlay → CreateWidget(WidgetClass, GetPlayerController(0)) → store as variable → AddToViewport(Widget, ZOrder=0). Remove: RemoveFromParent(Widget). Toggle: SetVisibility(Collapsed/Visible). Create once, toggle visibility — never recreate every frame. For interaction: SetInputModeUIOnly + SetShowMouseCursor.

Widget data binding: update UI automatically when variable changes

METHOD 1 - Function Binding (auto-updates every frame, easy but has perf cost): In Widget BP: select TextBlock → Details → Content → Text → click 'Bind' → Create Binding → connect your data (e.g. GetPlayerHealth as Text). METHOD 2 - Event-driven (recommended, update only when needed): In owning actor: when data changes → CastTo<WBP_HUD>(HUDWidget) → call custom function 'UpdateHealth(NewHealth)' on widget. In Widget BP: UpdateHealth function → SetText(HealthText, Conv_FloatToString(NewHealth)). KEY: Function bindings run every frame. For frequently-changing data (Tick-speed), use Event-driven approach instead to avoid perf issues.

PlayAnimation (widget) — play a Widget Animation

Create widget, add to viewport, and store reference

Pattern: EventBeginPlay → CreateWidget(OwningPlayer=GetPlayerController, WidgetType=WBP_MyWidget) → SetVariable(HUDWidget=ReturnValue) → CastTo<WBP_MyWidget>(HUDWidget) → Cast Succeeded → AddToViewport(ZOrder=0). Always store widget reference in a variable. CreateWidget inputs: 'OwningPlayer' (PlayerController) and 'WidgetType' (class). Exec in='execute', exec out='then'.

PlayAnimation on widget — play UMG widget animation

CreateWidget — create widget instance from class

K2Node_CreateWidget. Class is the Widget Blueprint class reference.

SetVisibility widget — show or hide widget

ESlateVisibility: Visible, Collapsed, Hidden, HitTestInvisible, SelfHitTestInvisible.

SetText on TextBlock — set display text on UI text widget

UTextBlock::SetText. Bind widget reference with BindWidget meta or GetWidgetFromName.

SetColorAndOpacity on widget — change widget color and transparency

Widget health bar HUD that updates from player health variable

Pattern: WBP_HealthBar with ProgressBar(HealthBar, BindWidget). Player BeginPlay: CreateWidget(WBP_HealthBar, PC) → SET WidgetRef → AddToViewport. On health change: WidgetRef → SetPercent(HealthBar, CurrentHealth/MaxHealth). Alternative: use property binding in widget designer for auto-update.