Struct TextArea 

pub struct TextArea<'a, C: PixelColor, M: Clone> { /* private fields */ }

Editable multi-line text field.

Borrows the text as Cow<'a, str> and reads a host-owned cursor position (char index). It emits a message via on_tap carrying the nearest char index when tapped, so the host can move its cursor.

Implementations

impl<'a, C: PixelColor, M: Clone> TextArea<'a, C, M>

pub fn new(text: impl Into<Cow<'a, str>>) -> Self

New text area displaying text. The cursor defaults to index 0; set it with cursor. Position and size are assigned by the parent container via arrange.

pub fn cursor(self, index: usize) -> Self

Cursor position as a char index into the text. Values past the end are clamped to the char count at draw time.

pub fn placeholder(self, text: impl Into<Cow<'a, str>>) -> Self

Dimmed placeholder shown when the text is empty.

pub fn id(self, id: WidgetId) -> Self

Set a stable id so this text area can participate in focus traversal.

pub fn color(self, color: C) -> Self

Override the text color (default: theme.background.on_base).

pub fn cursor_color(self, color: C) -> Self

Override the cursor bar color (default: theme.accent.base).

pub fn placeholder_color(self, color: C) -> Self

Override the placeholder color (default: theme.palette.neutral_2).

pub fn font(self, font: &'a MonoFont<'a>) -> Self

Override the font (default: theme.default_font()). Must be a mono font; wrapping relies on character_size.width.

pub fn on_tap<F: Fn(usize) -> M + 'a>(self, f: F) -> Self

Callback receiving the nearest char index when the area is tapped. Without it, taps are ignored. The host typically stores the returned index as its new cursor position.

Tap-to-cursor mapping requires an explicit font (the theme is not reachable during touch dispatch); without one, taps are silently ignored.

pub fn on_action<F: Fn(UiAction) -> M + 'a>(self, f: F) -> Self

Callback receiving semantic editing/navigation actions while focused.

pub fn width(self, width: impl Into<Length>) -> Self

Width sizing intent.

pub fn height(self, height: impl Into<Length>) -> Self

Height sizing intent.

Trait Implementations

impl<'a, C: PixelColor, M: Clone> Widget<C, M> for TextArea<'a, C, M>

fn measure(&mut self, constraints: Constraints) -> Size

Report the size this widget wants within constraints.

fn preferred_size(&self) -> (Length, Length)

Per-axis sizing intent set via .width(...) / .height(...). Containers consult this during layout to allocate fixed slots, query intrinsic sizes, and split residual space among Fill / FillPortion children. Default is Length::Fill on both axes.

fn arrange(&mut self, rect: Rectangle)

Commit the final rectangle, recursively arranging any children.

fn rect(&self) -> Rectangle

The current arranged rectangle.

fn handle_touch(&mut self, point: Point, phase: TouchPhase) -> Option<M>

Dispatch a touch event. Returns a message if consumed.

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

Stable id of this widget, if it participates in focus.

fn is_focusable(&self) -> bool

True if this widget should appear in focus traversal.

fn handle_action(&mut self, action: UiAction) -> Option<M>

Handle a semantic action directed at this widget.

fn sync_focus(&mut self, focused: Option<WidgetId>)

Synchronize focused state against the runtime’s currently-focused id.

fn focus_at(&self, point: Point) -> Option<WidgetId>

Focusable widget id at point, if any.

fn draw<'t>( &self, renderer: &mut dyn Renderer<C>, theme: &Theme<'t, C>, ) -> Result<(), RenderError>

Paint into renderer at rect.

fn mark_pressed(&mut self, point: Point)

Set this widget’s pressed flag if point hits. No message emit. Containers forward to children. Default no-op.

fn collect_focusable(&self, out: &mut Vec<WidgetId>)

Append focusable widget ids in traversal order.

fn route_action(&mut self, target: WidgetId, action: UiAction) -> Option<M>

Route a semantic action to the widget with id target.

fn navigate_focus(&self, target: WidgetId, action: UiAction) -> Option<WidgetId>

Request a focus movement relative to target for directional actions.

fn focus_rect(&self, target: WidgetId) -> Option<Rectangle>

Rectangle currently occupied by the focusable target, if any.