Struct CodeEditor 

pub struct CodeEditor { /* private fields */ }

A multi-line source-code editing surface: gutter, current-line highlight, indentation, bracket handling, and multiple carets.

Construct with CodeEditor::new (editable) or CodeEditor::read_only (view + select + copy). Every code affordance is injected configuration, not a built-in language — see CodeConfig.

Implementations

impl CodeEditor

pub fn new(document: TextDocument) -> Self

An editable code editor bound to document: gutter on, current-line highlight on, no wrapping. Code affordances (comment token, bracket pairs) stay off until the application supplies them — the editor never guesses a language.

pub fn read_only(document: TextDocument) -> Self

A read-only code viewer bound to document: no caret, navigation and copy only, Role::Document. Still gets the gutter and syntax colours.

pub fn wrap_mode(self, mode: WrapMode) -> Self

Set the line-wrap mode. CodeEditor defaults to WrapMode::None (source lines must not fold, or the gutter’s one-number-per-line correspondence breaks); pair with .h_scroll_policy(Auto) to scroll wide lines.

pub fn v_scroll_policy(self, policy: ScrollPolicy) -> Self

Vertical scrollbar policy (default Auto).

pub fn h_scroll_policy(self, policy: ScrollPolicy) -> Self

Horizontal scrollbar policy (default Auto).

pub fn overscroll_behavior(self, behavior: OverscrollBehavior) -> Self

Wheel scroll-chaining at the editor’s scroll boundary. Chain (default) hands leftover scroll to an enclosing scrollable; Contain absorbs it.

pub fn window_to_clip(self, on: bool) -> Self

Cull the render to the visible clip band (default false). Turn on only for an editor deliberately laid out at full document height inside an outer ScrollArea (v_scroll_policy(AlwaysOff) + min_lines(1)): the body’s bounds then span the whole document, and this renders only the on-screen slice instead of every line. A normally-scrolling editor already renders just a viewport’s worth, so it needs nothing.

pub fn min_lines(self, lines: u32) -> Self

Minimum visible height in lines — switches the editor from greedy (fill the proposal) to intrinsic sizing (grow with content up to max_lines, then scroll). The composer pattern.

pub fn max_lines(self, lines: u32) -> Self

Maximum visible height in lines — caps intrinsic growth.

pub fn font_family(self, family: impl Into<String>) -> Self

Fallback font family for the document’s text. None (the default) keeps the typesetter’s registry default; a code editor should pass a monospace family so columns line up.

pub fn font_size_scale(self, scale: f32) -> Self

Per-editor logical font-size multiplier (1.0 = 100 %), composed with the accessibility text scale when follow_text_scale is on. Sharp — shapes at a larger ppem.

pub fn follow_text_scale(self, follow: bool) -> Self

Whether the editor grows text with the global accessibility text scale (default true). Turn off for a WYSIWYG surface whose font sizes are document content. Composed with font_size_scale.

pub fn on_change(self, callback: impl Fn() + 'static) -> Self

A callback fired once per drain batch that contained a real content edit.

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

Override the editor background colour (accepts Color, a theme role, or a Signal). None-equivalent default tracks the theme’s editor_bg.

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

Override the text colour. Default tracks the theme’s editor_fg.

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

Override the caret colour. Default tracks the theme’s editor_caret.

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

Override the selection colour. A pinned colour opts out of the window-inactive desaturation.

pub fn gutter(self, show: bool) -> Self

Whether the line-number gutter is shown (default true).

pub fn current_line_highlight(self, on: bool) -> Self

Whether the caret’s line gets a full-width background wash (default true for CodeEditor).

pub fn indent_style(self, style: IndentStyle) -> Self

Set the indentation style directly (spaces of a width, or tabs rendered a width wide).

pub fn tab_width(self, width: u8) -> Self

Set the indent width, keeping the current spaces-vs-tabs kind.

pub fn use_soft_tabs(self, soft: bool) -> Self

Whether indentation is written with spaces (true, the default) or a tab character (false), keeping the current width.

pub fn auto_indent(self, on: bool) -> Self

Whether Enter carries the current line’s indentation onto the new line (default true).

pub fn bracket_pairs(self, pairs: impl Into<Vec<BracketPair>>) -> Self

The delimiter pairs the editor auto-closes and match-highlights. Empty (the default) disables both.

pub fn auto_close_brackets(self, on: bool) -> Self

Whether typing an opener inserts its closing partner (default false; needs configured bracket_pairs).

pub fn bracket_matching(self, on: bool) -> Self

Whether the delimiter matching the caret’s is highlighted (default false; needs configured bracket_pairs).

pub fn line_comment(self, token: impl Into<String>) -> Self

The token that starts a line comment ("//", "#", "--"). Enables Ctrl+/ comment toggling; unset (the default) leaves it a no-op rather than guessing.

pub fn completion_provider( self, provider: impl Fn(&CompletionContext<'_>) -> Vec<CompletionItem> + 'static, ) -> Self

Supply the completion candidates. The provider is called for the word being completed and given a CompletionContext; the editor filters its result by the live prefix, shows the popup, and replaces the word on accept. Language-agnostic — the app knows the candidates, the editor knows the mechanics. Without a provider there is no completion.

pub fn auto_complete(self, auto: bool) -> Self

Whether typing an identifier character opens the completion popup automatically (default true). When off, only Ctrl+Space opens it.

pub fn handle(&self) -> CodeEditorHandle

A cloneable handle to drive the editor from a toolbar, shortcut, or test.

Trait Implementations

impl Debug for CodeEditor

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

Formats the value using the given formatter.

impl Widget for CodeEditor

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

Compose child widgets. Called once after the widget is placed in the arena, and again on environment change (theme switch, locale switch). 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 place_children( &self, bounds: Rect, _proposal: SizeProposal, children: &mut [WidgetPlacement], ctx: &LayoutContext<'_>, )

Position children within the allocated bounds.

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 children(&self) -> Vec<WidgetId>

Return the child widget IDs that this widget manages.

fn clips_children(&self) -> bool

Whether this widget clips its children to its bounds.

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 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 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 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 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 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).