Struct AppBarView 

pub struct AppBarView<State: 'static> { /* private fields */ }

A declarative M3 fixed top app bar. See the module docs.

Implementations

impl<State: 'static> AppBarView<State>

pub fn leading(self, leading: impl View<State>) -> Self

Attach a leading slot (typically a nav/back icon button), erased as an AnyView. Tint is the supplied view’s own responsibility — see super’s slot contract.

pub fn actions<M>(self, actions: impl ViewSeq<State, M>) -> Self

Attach trailing action slots, in reading order (the last one sits closest to the trailing edge). Tint is each supplied view’s own responsibility.

pub fn title_view(self, title: impl View<State>) -> Self

Replace the title string with a caller view — upstream’s title widget slot, which takes precedence over its titleText. The view is placed but never styled, and (unlike a string title) labels itself for accessibility.

pub fn center_title(self, center: bool) -> Self

Center the title within the space left between the leading slot and the actions (centerTitle, default false).

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

Shift the row out from under a protruding window-control corner (default true). Pass false for a bar that does not span the window’s top edge (detail pane, sheet, dialog, below other content): layout cannot see the bar’s window-space position and the corner value is never consumed, so such a bar would otherwise over-shift.

pub fn density(self, density: AppBarDensity) -> Self

Set the vertical density — see super’s metrics table.

pub fn shape_family(self, family: AppBarShapeFamily) -> Self

Set the container’s corner shape family (default AppBarShapeFamily::Square, upstream’s own M3EAppBar.top default).

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

Override the band height outright (toolbarHeight), bypassing the density table — the seam that reaches upstream’s own 72dp band, among anything else.

pub fn background(self, color: Color) -> Self

Override the container fill (backgroundColor), winning over Self::container, the elevation surface role, the theme default and its fallback alike.

pub fn container(self, role: AppBarContainer) -> Self

Fill the container with a theme color role (default AppBarContainer::Surface), resolved at paint time so it follows a brightness flip or theme swap. An explicit role also wins over the elevation surface role Self::elevation would otherwise pick, and a string title takes the role’s foreground (see AppBarContainer). Self::background still wins over it.

use frust_material::{AppBarContainer, app_bar};

// Flutter's counter-template bar: an inverse-primary fill, raised.
let bar = app_bar::<()>("Counter")
    .container(AppBarContainer::InversePrimary)
    .elevation(2);

pub fn elevation(self, level: u8) -> Self

Raise the bar to M3 elevation level (0..=5, clamped; default 0), resolved at paint time against the theme’s elevation table: a level above 0 paints that level’s drop shadow beneath the container and, with no Self::container/Self::background set, fills with the level’s surface role (level 2 is surfaceContainer). See super’s module docs for the paint order.

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

Whether the bar consumes the top, left and right window insets itself (default true) — Flutter’s AppBar wrapping its toolbar in SafeArea(bottom: false). It grows by ctx.window_insets().padding().top, paints its fill (and shadow) edge to edge through that band and across the full width, and lays its slots out below the top inset and inside the left/right ones (a landscape notch or home-indicator edge). A parent frust::safe_area that already consumed an edge leaves nothing on it to consume, so it never double-insets. Pass false for a bar that is not docked to the window’s top edge (a preview, a pane, a sheet); it then consumes no edge at all.

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

Label the bar’s accessibility container explicitly (semanticLabel). Without one, a string title labels it and a caller view leaves it unlabelled.

Trait Implementations

impl<State: 'static> View<State> for AppBarView<State>

type Element = AppBarWidget

The retained widget this view produces.

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

Materialise a fresh widget for this view.

fn rebuild( &self, prev: &Self, element: &mut AppBarWidget, 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 AppBarWidget, 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.