Struct TextWidget 

pub struct TextWidget { /* private fields */ }

Implementations

impl TextWidget

pub fn new(text: impl Into<LocalizedString>) -> Self

Construct a text widget whose content is a LocalizedString. The text may come from tr!(...) (reactive, re-resolves on locale change) or from lit!("…") for genuinely non-translated strings.

pub fn color(self, color: impl Into<ColorProp>) -> Self

Set the text color. Accepts any impl Into<ColorProp>:

• A raw Color — a frozen literal.
• A TextRole — resolved against the theme at paint time (reactive across theme switches).
• A Signal<Color> — reactive state (typically interaction-driven).

The default role is TextRole::Primary, so .color(...) is only needed when a label wants a non-default theme role (Secondary, Error, Accent, …) or a custom color.

pub fn style(self, style: impl Into<TextStyleProp>) -> Self

Set the text style. Accepts a raw TextStyle, a TextStyleRole, or any value implementing Into<TextStyleProp>. Using a role resolves at paint/layout time, so theme typography changes take effect without a rebuild.

pub fn overflow(self, overflow: TextOverflow) -> Self

Set how the widget handles text that doesn’t fit in the proposed width. Default is TextOverflow::Wrap.

pub fn single_line(self) -> Self

Shorthand for .overflow(TextOverflow::Ellipsis(EllipsisMode::Trailing)). Use this on labels inside single-line containers (buttons, menu items, tab headers, badges, status bar cells, etc.) so long text truncates with a trailing “…” instead of wrapping onto multiple lines.

pub fn min_shrink_width(self, min: f32) -> Self

Override the compression floor for single-line / ellipsis text — the narrowest width an over-constrained stack may shrink this label to before truncating stops. Defaults to the ellipsis-glyph width.

pub fn no_shrink(self) -> Self

Opt this label out of native shrink: it reports a rigid size and overflows (rather than truncating) when its stack is over-constrained.

pub fn max_lines(self, n: usize) -> Self

Cap the paragraph at n lines when wrapping. Only meaningful in TextOverflow::Wrap mode — ignored for ellipsis modes. Lines beyond the cap are silently dropped.

pub fn text_backend(self, backend: Rc<RefCell<dyn TextBackend>>) -> Self

Override the text backend used for measurement and rasterization. In normal app code the framework provides the backend automatically; this method is used by headless tests that inject a MockTextBackend.

pub fn text(self, state: impl Into<Prop<String>>) -> Self

Set the text content. Accepts a static String/&str or a reactive Signal<String> / Prop<String> (resolved and re-rendered on change).

pub fn resolved_text(&self) -> String

Get the current text value (resolves from state if bound).

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

Enable inline markup parsing. When enabled, the text is parsed as a minimal markdown subset:

• [label](url) — inline link
• *italic* — italic run
• **bold** — bold run

Links are dispatched via on_link_click and colored using theme.colors.text_link.

pub fn on_link_click<F>(self, handler: F) -> Self

where F: Fn(&str, &mut EventContext<'_>) + 'static,

Called when an inline link is tapped. Enables markup automatically.

pub fn on_link_hover<F>(self, handler: F) -> Self

where F: Fn(&str, bool, Rect, &mut EventContext<'_>) + 'static,

Called when an inline link is hovered (enter/leave). Receives the URL, a bool indicating whether the pointer entered (true) or left (false), and the widget-local rect of the link span (so anchoring popups next to the link is cheap). Enables markup automatically.

pub fn a11y_hidden(self) -> Self

Hide this text from the accessibility tree. Use this when the TextWidget is a visual label fragment inside another control that already owns its accessible name via set_name — otherwise screen readers announce the same string twice (once for the control, once for the embedded Label node).

Standalone body text (dialog descriptions, form instructions, read-only display values) should NOT set this — it stays as a Role::Label node.

pub fn geometry_handle(&self) -> TextGeometryHandle

A handle onto what this label last measured.

For the controls that own their accessible name but paint their text through a hidden TextWidget — Badge, GroupHeader — and so have to emit that text’s runs from their own node. The handle is empty until the label has been placed, and the geometry it carries is in window space, so the borrower reports it as absolute.

The borrower must place the donor rigidly at its own origin: a move re-places absolute rects by the borrower’s delta, so a composite that repositions its donor independently should register local rects instead.

Trait Implementations

impl Debug for TextWidget

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl Widget for TextWidget

fn place_children( &self, bounds: Rect, _proposal: SizeProposal, _children: &mut [WidgetPlacement], ctx: &LayoutContext<'_>, )

Shape once more at the final width, and keep what came back.

This is the only pass that sees the width the label actually got: layout_response runs speculatively, more than once, at proposals the parent may not honour. The accessibility tree needs the real one — a label that wraps at 200 dp has a different set of lines, and therefore of text runs, from the same label at 400 dp.

The call mirrors paint’s exactly, including its + 0.5 width epsilon, so both land on the same backend cache entry. Under a scale transform (a zoomed SceneView, a Scale wrapper) the ambient raster scale differs between this pass and paint, so the two hit different entries: the metrics are identical — the cache keys on raster scale only for glyph density — and the geometry is right either way, at the cost of one extra shaping per (text, scale).

fn build(&mut self, ctx: &mut BuildContext<'_>) -> Vec<WidgetId>

Compose child widgets. Called once after the widget is placed in the arena, and again whenever the widget is marked for rebuild — a BindingLevel::Rebuild binding, rebuild_single_widget, or a density switch. A theme or locale switch does not rebuild: set_theme and set_locale mark layout + paint dirty and leave the built subtree standing, so anything derived from the theme or the locale must be read per pass or bound to a signal rather than captured here. Takes &mut self — store child IDs, signal handles, any state needed later. Returns the list of root child IDs (empty for leaf widgets).

fn layout_response( &self, proposal: SizeProposal, ctx: &LayoutContext<'_>, ) -> LayoutResponse

Respond to the parent’s size proposal with this widget’s wanted size, grow/shrink weights, and compression floor (see LayoutResponse).

fn paint(&self, bounds: Rect, canvas: &mut Canvas, ctx: &PaintContext<'_>)

Draw the widget’s visual representation.

fn accessibility(&self, builder: &mut AccessNodeBuilder)

Declare this widget’s accessibility identity.

fn type_name(&self) -> &'static str

Concrete type name of this widget (e.g. "teksilo_widgets::button::Button"). The default implementation resolves at the impl site via std::any::type_name::<Self>(), so calls through &dyn Widget correctly dispatch to the monomorphized fn for the concrete type — getting the concrete name through the vtable without per-impl boilerplate.

fn cacheable_layout(&self) -> bool

Whether this widget’s layout_response may be memoized by the per-pass layout cache. Defaults to true.

fn wants_after_paint(&self) -> bool

Whether this widget wants its after_paint hook to fire each frame. Returning false (the default) saves a virtual call per widget per frame for the vast majority of widgets that don’t aggregate descendant geometry.

fn after_paint(&self, _view: &WidgetTreeView<'_>, _ctx: &PaintContext<'_>)

Called once per frame after this widget’s subtree has finished painting. Receives a read-only view of the layout-resolved arena so a parent can read its descendants’ final bounds — e.g. TitleBar aggregates its drag region and control-button rects into a single HitRegions payload for the Windows backend’s WM_NCHITTEST.

fn wants_post_paint(&self) -> bool

Whether this widget wants its post_paint hook to fire each frame. Returning false (the default) saves a virtual call per widget per frame for the vast majority of widgets that don’t draw a foreground over their children.

fn post_paint( &self, _bounds: Rect, _canvas: &mut Canvas, _ctx: &PaintContext<'_>, )

Draw a foreground layer over this widget’s children.

fn wants_descendant_redirects(&self) -> bool

Whether this widget wants the AT walker to consult its a11y_redirect_descendant hook for every descendant during AT tree emission, not just its direct arena children.

fn culls_children(&self) -> bool

Whether this widget decides, on every layout pass, which of its children exist at all.

fn a11y_redirect_descendant( &self, _self_id: WidgetId, _descendant: WidgetId, ) -> Option<NodeId>

Optional redirection hook for AT-tree placement of a child.

fn accessible_title_hint(&self) -> Option<String>

Suggest an accessible title to an enclosing container that wraps this widget as content — typically a modal / dialog shell that wants to propagate the inner content’s visible title as the shell’s own accessible name.

fn accessible_title_node(&self) -> Option<WidgetId>

The widget that paints this one’s title, when it has one.

fn initial_focus_hint(&self) -> Option<WidgetId>

Optional hint that directs initial focus to a specific descendant when this widget is the root of a deferred-built modal surface.

fn context_menu_key_target(&self) -> Option<WidgetId>

Which descendant a keyboard request for a context menu should target.

fn children(&self) -> Vec<WidgetId>

Return the child widget IDs that this widget manages.

fn accessibility_children(&self) -> Option<Vec<WidgetId>>

Optional override for the child ORDER presented to assistive technology, when it must differ from the paint / z-order child order returned by children.

fn as_any(&self) -> Option<&(dyn Any + 'static)>

Downcast hook. Default implementation returns None; concrete widgets override with Some(self) when they want to expose their concrete type to test-level introspection or reflection. The trait already bounds on std::any::Any so concrete types satisfy the 'static requirement.

fn as_any_mut(&mut self) -> Option<&mut (dyn Any + 'static)>

Mutable counterpart of as_any. Default returns None; widgets that want to expose mutable state to tests (e.g. so a test can mutate a Scene inside a SceneView post-layout) override with Some(self). Should follow the same opt-in pattern as as_any: only widgets that opt into & introspection should opt into &mut.

fn clips_children(&self) -> bool

Whether this widget clips its children to its bounds.

fn focus_reveal_rect(&self, _bounds: Rect) -> Option<Rect>

The rectangle (in absolute tree coordinates) that best represents this widget when the framework reveals it into an ancestor scroll area on focus gain. Returning None (the default) reveals the widget’s whole bounds — correct for most controls.

fn hit_shape(&self, _local_point: Point, _bounds: Rect) -> bool

Whether the point lies inside this widget’s actual shape, not just its rectangular bounds. Consulted by hit-testing right after the bounds check: returning false for a point that is inside the bounding box makes the widget transparent to the click there, so it falls through to whatever sibling is painted underneath (the same machinery as a fully pass-through node, but shape-aware).

fn accepts_child_hit(&self, _child: WidgetId, _point: Point) -> bool

Veto a hit on one of this widget’s direct children, per point.

fn hit_outset(&self, _kind: PointerKind, _tokens: &InputTokens) -> EdgeInsets

How far outside its own bounds this widget still absorbs a press, per edge, for the pointer that is asking.

fn hit_slop(&self, _kind: PointerKind, _tokens: &InputTokens) -> Option<HitSlop>

This widget’s own say in the miss-only slop pass, overriding the density default for its node.

fn hit_distance(&self, local_point: Point, bounds: Rect) -> Option<f32>

How far a missed press is from this widget’s actual silhouette, in the widget’s own bounds space.

fn target_regions(&self, _bounds: Rect) -> Vec<TargetRegion>

The interactive sub-regions this widget paints inside its own single node — a scroll bar’s thumb, a slider’s knob, a header cell’s filter affordance.

fn preserves_children_on_rebuild(&self) -> bool

How rebuild_single_widget treats this widget’s existing children when re-running its build().

fn tooltip_has_content(&self) -> bool

Whether this widget, used as tooltip content, currently has anything worth showing.

fn declare_shortcuts(&self) -> Vec<Shortcut>

Declare the rebindable keyboard shortcuts this widget exposes, without installing handlers. The framework calls this at arena insertion time (before build()) and at certain lazy boundaries (e.g. Switcher walks declarations on its not-yet-mounted Pending slots), so settings UIs and the ShortcutRegistry see the keystrokes the moment the owning container mounts — even if build() hasn’t run.

fn take_handler_set(&mut self) -> Option<HandlerSet>

Extract attached handler set from a WidgetWithHandlers wrapper. Called during arena insertion to transfer handlers to the WidgetNode. Default: returns None (no attached handlers).

impl WidgetCatalog for TextWidget

fn id() -> &'static str

Stable, ASCII id (e.g. "button", "tag_chip"). Used in CLI args, navigator URLs, and persistence keys.

fn group() -> &'static str

Group label for navigator organisation ("Controls", "Containers", "Composites", …).

fn display_name() -> &'static str

Human-readable label shown in the navigator.

fn knobs() -> KnobSpec

Optional knob declarations. Empty by default — composite widgets that build via Scenario variants leave this empty.

fn variants() -> Vec<PreviewVariant>

Named variants. At least one is required — typically a “default”.

fn build(_variant: &str, knobs: &KnobValues) -> Box<dyn Widget>

Construct a fresh widget instance for the named variant, given runtime knob values. The implementation typically dispatches on the variant name to handle Scenario paths and otherwise builds via the knob values for Knobs variants.

fn icon() -> Option<Box<dyn Widget>>

An icon widget for the navigator palette and the designer’s outline tree. None (the default) leaves the consumer to substitute a generic fallback. Returns a Box<dyn Widget> (not an IconWidget) so this crate stays free of any widgets-crate dependency.

fn category() -> WidgetCategory

How this widget accepts children. The default, WidgetCategory::Leaf, is correct for every control; container widgets override it.

fn slots() -> &'static [&'static str]

Named slots for a WidgetCategory::ContainerB widget (e.g. Card → ["header", "content", "footer"]). Empty for Leaf and ContainerA.

fn build_with_children( variant: &str, knobs: &KnobValues, children: Vec<SlottedChild>, ) -> Box<dyn Widget>

Build with pre-registered children injected. ContainerA folds children as ordered bare children; ContainerB routes each by its slot name; Leaf ignores them. The default ignores children and delegates to build, so non-container widgets need no override.