Struct NativeStepperView 

pub struct NativeStepperView { /* private fields */ }

A real increment/decrement control rendered from pure Rust — UIStepper on iOS/iPadOS, NSStepper on macOS, and a frust-drawn refusal banner everywhere else (Android included: see [STEPPER_ARM]). A controlled component, like NativeSliderView: the app owns value, and a tap on either button only ever arrives through Self::on_change as a requested value. Build one with native_stepper.

min/max/Self::step are normalized before they ever reach a platform control (crate::controls::stepper’s module doc’s Range and step invariants: UIStepper aborts the process on a non-positive stepValue or a maximumValue not strictly greater than minimumValue). A degenerate range (max <= min) renders the control disabled — the user can never tap it, and no value outside [min, max] is ever reported — rather than refusing to mount or crashing; it re-enables the moment a later update makes the range non-degenerate again.

Implementations

impl NativeStepperView

pub fn step(self, step: i32) -> Self

The increment a tap on either button applies — default 1. A non-positive value (0 or negative) is normalized to 1 before it ever reaches a platform control, logged once per process — UIStepper requires stepValue > 0 (crate::controls::stepper’s module doc’s Range and step invariants).

pub fn wraps(self, wraps: bool) -> Self

Whether the value wraps from max back to min (and back) instead of clamping at the bounds — default false.

pub fn enabled(self, enabled: bool) -> Self

UIControl.enabled / NSControl.enabled — default true.

pub fn content_description(self, label: impl Into<String>) -> Self

The VoiceOver label.

pub fn size(self, width: f64, height: f64) -> Self

Explicit slot size — see [resolve_size]’s doc for the no-call fallback.

pub fn on_change(self, handler: impl Fn(i32) + Send + Sync + 'static) -> Self

Fires with the requested app-space value on a tap (crate::controls::stepper’s platform-space mapping already undone — the same mapping NativeSliderView::on_change documents). Never fires on a target with no stepper arm.

Trait Implementations

impl Clone for NativeStepperView

fn clone(&self) -> Self

Returns a duplicate of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Component for NativeStepperView

type State = u64

The retained local state this component owns across rebuilds.

fn init(&self) -> SlotId

Create the component’s initial local state. Runs exactly once, when the ComponentWidget is first built, under the component’s Owner (so on_cleanup/provide_context registered here bind to that owner).

fn build(&self, state: &mut SlotId) -> AnyView<SlotId>

Produce the component’s subtree from its current local state.

impl<Outer: 'static> View<Outer> for NativeStepperView

type Element = ComponentWidget<NativeStepperView>

The retained widget this view produces.

fn build(&self, ctx: &mut BuildCtx<'_>) -> Self::Element

Materialise a fresh widget for this view.

fn rebuild( &self, prev: &Self, element: &mut Self::Element, ctx: &mut BuildCtx<'_>, ) -> ChangeFlags

Reconcile prev (the previous view of the same type) against the live element, mutating it in place and reporting what changed.

fn teardown(&self, element: &mut Self::Element, ctx: &mut BuildCtx<'_>)

Tear down element when this view is being removed.

fn message(&self, _element: &mut Self::Element, _state: &mut State)

Deliver an event message to this view, mutating application state.