Struct TextField 

pub struct TextField {
    pub read_only: bool,
    pub select_all_on_focus: bool,
    pub password_mode: bool,
    pub placeholder: String,
    pub padding: f64,
    pub theme: TextFieldTheme,
    /* private fields */
}

Single-line editable text field.

Fields

read_only: bool

select_all_on_focus: bool

password_mode: bool

When true, every character is displayed as ‘•’ (U+2022). The actual text is stored and edited normally; only the render is masked.

placeholder: String

padding: f64

theme: TextFieldTheme

Per-widget colour overrides — None colours fall back to the ambient visuals() palette. Set via [with_theme].

Implementations

impl TextField

pub fn with_text_cell(self, cell: Rc<RefCell<String>>) -> Self

Bind the field to external text state.

layout picks up external writes (e.g. a Clear button) and on_change writes user edits back into the cell.

impl TextField

pub fn with_char_filter(self, filter: impl Fn(char) -> bool + 'static) -> Self

Install a per-character allow-list. Any character for which filter returns false is silently dropped from insertions — both single-character typing and multi-character paste. The text already in the field at install time is left alone.

Common patterns:

• decimal digits: |c| c.is_ascii_digit()
• hex seed with 0x prefix: |c| c.is_ascii_hexdigit() || c == 'x' || c == 'X'
• single-line: |c| c != '\n' && c != '\r'

impl TextField

pub fn with_focus_id(self, id: FocusId) -> Self

Assign a stable id for the programmatic focus channel. App code can then call crate::focus::request_focus(id) to move keyboard focus here (and raise the on-screen keyboard) the next frame — e.g. to auto-focus a search field when its overlay opens.

pub fn with_keyboard_mode(self, mode: KeyboardInputMode) -> Self

Set the preferred keyboard input mode for this field — picks which layer the on-screen software keyboard slides up into the next time this field gains focus. Defaults to KeyboardInputMode::Text.

This does not install a character filter: a numeric field still accepts whatever the user actually types (including via a paste or the on-screen ABC mode switch). Combine with TextField::with_char_filter when you want hard validation.

pub fn with_keyboard_mode_cell(self, cell: Rc<Cell<KeyboardInputMode>>) -> Self

Bind the field’s keyboard mode to an externally-owned cell. The caller keeps a clone and can flip the mode at any time — the next focus event re-queries the cell, so the keyboard re-targets without a widget rebuild. Mirrors the TextField::with_text_cell pattern.

pub fn keyboard_mode(&self) -> KeyboardInputMode

Read the current mode. Used by the Widget::text_input_mode override and exposed publicly so app code can inspect it without going through a dyn Widget trait dispatch.

pub fn set_keyboard_mode(&self, mode: KeyboardInputMode)

Update the mode at runtime — typically called from a callback (e.g. a radio button’s on_change). Equivalent to mutating the cell directly via TextField::keyboard_mode_handle but reads better at the call site.

pub fn keyboard_mode_handle(&self) -> Rc<Cell<KeyboardInputMode>>

Clone the underlying cell so a parent can drive this field’s mode from somewhere else in the tree (a radio button, a menu item, a feature-flag observer). Multiple fields can share the same handle to ride a single switch.

impl TextField

pub fn with_margin(self, m: Insets) -> Self

pub fn with_h_anchor(self, h: HAnchor) -> Self

pub fn with_v_anchor(self, v: VAnchor) -> Self

pub fn with_min_size(self, s: Size) -> Self

pub fn with_max_size(self, s: Size) -> Self

impl TextField

pub fn with_theme(self, theme: TextFieldTheme) -> Self

Install a TextFieldTheme of per-widget colour overrides. Any field set to None on the theme falls back to the ambient visuals() palette, so callers can override just what they need (e.g. background + border for a dark-panel field that keeps the default selection / cursor highlights).

impl TextField

pub fn new(font: Arc<Font>) -> Self

pub fn with_font_size(self, s: f64) -> Self

pub fn with_padding(self, p: f64) -> Self

pub fn with_read_only(self, v: bool) -> Self

pub fn with_select_all_on_focus(self, v: bool) -> Self

pub fn with_password_mode(self, v: bool) -> Self

pub fn with_placeholder(self, s: impl Into<String>) -> Self

pub fn with_text(self, s: impl Into<String>) -> Self

pub fn on_change(self, cb: impl FnMut(&str) + 'static) -> Self

pub fn on_enter(self, cb: impl FnMut(&str) + 'static) -> Self

pub fn on_edit_complete(self, cb: impl FnMut(&str) + 'static) -> Self

pub fn text(&self) -> String

pub fn cursor_pos(&self) -> usize

pub fn selection(&self) -> String

pub fn set_text(&mut self, s: impl Into<String>)

Trait Implementations

impl Widget for TextField

fn set_label_text(&mut self, text: &str)

Composite parents (e.g. ColorWheelPicker) use this to push a live value into the field without bypassing set_text’s cell sync and cache invalidation. Skipped while the field is focused so the user isn’t fighting the parent for cursor position mid-edit; the parent is expected to read back via TextField::text after focus is released to pick up any user-typed value.

fn needs_draw(&self) -> bool

While focused, the cursor blinks at 500 ms half-period. The field itself drives its own repaint cadence: [needs_draw] reports dirty whenever wall-clock time has crossed a flip boundary since the last paint, and [next_draw_deadline] returns the exact wall-clock instant of the next boundary so the host can WaitUntil it.

Losing focus makes both return None / false, and the tree walk’s visibility check drops the field entirely when its enclosing window is closed / collapsed / tab not selected — so an invisible focused field does NOT keep the loop awake.

fn paint_overlay(&mut self, ctx: &mut dyn DrawCtx)

Cursor overlay — runs AFTER the cache blit on every frame, so blink-phase flips don’t invalidate the backbuffer. Reads the same edit state paint() does so cursor lands on the glyph the cached text shows.

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

A static name for this widget type, used by the inspector. Default: “Widget”.

fn bounds(&self) -> Rect

Bounding rectangle in parent-local Y-up coordinates.

fn set_bounds(&mut self, b: Rect)

Set the bounding rectangle. Called by the parent during layout.

fn children(&self) -> &[Box<dyn Widget>]

Immutable access to child widgets.

fn children_mut(&mut self) -> &mut Vec<Box<dyn Widget>>

Mutable access to child widgets (required for event dispatch + layout).

fn is_focusable(&self) -> bool

Whether this widget can receive keyboard focus. Default: false.

fn focus_id(&self) -> Option<FocusId>

Stable identifier for the programmatic focus channel (crate::focus::request_focus).

fn accepts_text_input(&self) -> bool

true when this widget accepts free-form character input (typing arbitrary letters, numbers, punctuation). Used by the on-screen software keyboard (crate::widgets::on_screen_keyboard) to decide whether to slide up when this widget gains focus.

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

Current text contents of this widget if it is text-bearing. Used by the on-screen software keyboard to apply the sentence-start auto-capitalize heuristic: an empty field (or one ending in ., !, ?, newline) opens the keyboard with Shift active.

fn text_input_mode(&self) -> KeyboardInputMode

Preferred keyboard input mode for this widget — used by the on-screen software keyboard to pick the initial layer when this widget gains focus. Default is KeyboardInputMode::Text; numeric fields override to Numeric so the digit pad slides up instead of the letter row.

fn next_draw_deadline(&self) -> Option<Instant>

Return the earliest wall-clock instant at which this widget (or any visible descendant) wants the next draw. None = no scheduled wake. The host loop turns a Some(t) into ControlFlow::WaitUntil(t) so e.g. a cursor blink fires without continuous polling.

fn margin(&self) -> Insets

Outer margin around this widget in logical units.

fn widget_base(&self) -> Option<&WidgetBase>

Direct read access to the widget’s embedded WidgetBase.

fn widget_base_mut(&mut self) -> Option<&mut WidgetBase>

Mutable counterpart of widget_base.

fn h_anchor(&self) -> HAnchor

Horizontal anchor: how this widget sizes/positions itself horizontally within the slot the parent assigns. Default: HAnchor::FIT (take natural content width).

fn v_anchor(&self) -> VAnchor

Vertical anchor: how this widget sizes/positions itself vertically within the slot the parent assigns. Default: VAnchor::FIT (take natural content height).

fn min_size(&self) -> Size

Minimum size constraint (logical units).

fn max_size(&self) -> Size

Maximum size constraint (logical units).

fn backbuffer_cache_mut(&mut self) -> Option<&mut BackbufferCache>

Opt into per-widget CPU bitmap caching with a dirty flag.

fn backbuffer_mode(&self) -> BackbufferMode

Storage format for this widget’s backbuffer. Ignored unless [backbuffer_cache_mut] returns Some. Default BackbufferMode::Rgba — correct for any widget. Opt into BackbufferMode::LcdCoverage only when the widget paints opaque content covering its full bounds.

fn layout(&mut self, available: Size) -> Size

Compute desired size given available space, and update internal layout.

fn paint(&mut self, ctx: &mut dyn DrawCtx)

Paint this widget’s own content into ctx.

fn on_event(&mut self, event: &Event) -> EventResult

Handle an event. The event’s positions are already in local Y-up coordinates. Return EventResult::Consumed to stop bubbling.

fn hit_test(&self, local_pos: Point) -> bool

Return true if local_pos (in this widget’s local coordinates) falls inside this widget’s interactive area. Default: axis-aligned rect test.

fn claims_pointer_exclusively(&self, _local_pos: Point) -> bool

When true, hit_test_subtree stops recursing into this widget’s children and returns this widget as the hit target. Used for floating overlays (e.g. a scrollbar painted above its content) that must claim the pointer before children that happen to share the same pixels. Default: false.

fn hit_test_global_overlay(&self, _local_pos: Point) -> bool

Return true when local_pos hits an app-level overlay owned by this widget. Unlike normal hit testing, ancestors may be missed because the overlay is painted outside their bounds.

fn has_active_modal(&self) -> bool

Whether this widget currently owns an app-modal interaction layer.

fn on_unconsumed_key( &mut self, _key: &Key, _modifiers: Modifiers, ) -> EventResult

Handle a key that was not consumed by the focused widget path.

fn id(&self) -> Option<&str>

Optional human-readable identifier for this widget instance.

fn is_visible(&self) -> bool

Return false to suppress painting this widget and all its children. The widget’s own paint() will not be called. Default: true.

fn properties(&self) -> Vec<(&'static str, String)>

Return type-specific properties for the inspector properties pane.

fn try_scroll_to_lift(&mut self, _amount: f64) -> f64

Try to lift this widget’s visible content upward by amount pixels. Used by the on-screen-keyboard auto-scroll so a focused text field doesn’t end up hidden behind the keyboard panel: the App walks UP the focus path and asks each ancestor to absorb some of the deficit.

fn set_label_color(&mut self, _color: Color)

If this widget is text-bearing (e.g. Label), update its foreground colour. Default is a no-op. Composite widgets call this on their children to retint labels without rebuilding them — used by Button when toggling between active (white text on accent) and inactive (theme text on subtle bg) appearances.

fn as_reflect(&self) -> Option<&dyn Reflect>

Opt-in reflection accessor for the inspector’s typed property editors.

fn as_reflect_mut(&mut self) -> Option<&mut dyn Reflect>

Mutable counterpart of as_reflect. Used by the inspector to write edits back into the live widget.

fn has_backbuffer(&self) -> bool

Whether this widget renders into its own offscreen buffer before compositing into the parent.

fn compositing_layer(&mut self) -> Option<CompositingLayer>

Request that this widget subtree be painted into a transient transparent compositing layer before being blended into its parent.

fn backbuffer_spec(&mut self) -> BackbufferSpec

Unified widget-owned backbuffer request.

fn backbuffer_state_mut(&mut self) -> Option<&mut BackbufferState>

Mutable retained backbuffer state for widgets that request a BackbufferSpec other than BackbufferKind::None.

fn mark_dirty(&mut self)

Mark this widget’s own retained surface dirty, if it owns one.

fn contributes_children_to_inspector(&self) -> bool

Whether the inspector should recurse into this widget’s children.

fn show_in_inspector(&self) -> bool

Return false to hide this widget (and its subtree) from the inspector node snapshot entirely. Intended for zero-size utility widgets such as layout-time watchers / tickers / invisible composers — they bloat the inspector tree without providing user-relevant information and, at scale, can make the inspector’s per-frame tree rebuild expensive.

fn lcd_preference(&self) -> Option<bool>

Per-widget LCD subpixel preference for backbuffered text rendering.

fn finish_paint(&mut self, _ctx: &mut dyn DrawCtx)

Called after paint, child painting, and optional overlay painting.

fn paint_global_overlay(&mut self, _ctx: &mut dyn DrawCtx)

Paint app-level overlays after the entire widget tree has been painted.

fn clip_children_rect(&self) -> Option<(f64, f64, f64, f64)>

Return a clip rectangle (in local coordinates) that constrains all child painting. paint_subtree applies this clip before recursing into children, then restores the previous clip state afterward. The clip does not affect paint_overlay, which runs after the clip is removed.

fn inspector_child_transform(&self) -> TransAffine

Affine transform applied between this widget and its children during inspector traversal. Mirrors what paint() does — e.g. a widget that pushes pan/zoom in paint() and pops it in finish_paint() makes the framework recurse into its children with pan/zoom active, so collect_inspector_nodes must apply the same transform when accumulating descendant screen bounds. Without this hook the inspector hover overlay lands at the un-transformed canvas position when the widget sits inside a panning/zooming container.

fn padding(&self) -> Insets

Inner padding — space the widget reserves between its own bounds and its child layout area. Only container widgets carry padding; leaf widgets default to Insets::ZERO.

fn enforce_integer_bounds(&self) -> bool

Whether paint_subtree should snap this widget’s incoming translation to the physical pixel grid.

fn measure_min_height(&self, _available_w: f64) -> f64

Report the minimum height this widget needs to fully render its content when given the supplied available_w for width.

fn take_raise_request(&mut self) -> bool

Container widgets (notably crate::widgets::Stack) call this on each child at the start of layout(). A widget that returns true is moved to the END of its parent’s child list — painted last, i.e. raised to the top of the z-order. take_ semantics: the call is also expected to clear the request so the child doesn’t keep getting raised every frame.