Struct DropZone 

pub struct DropZone { /* private fields */ }

A drop target for external (OS) drag-and-drop. See the module docs.

Implementations

impl DropZone

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

Build a drop zone with the given prompt (e.g. tr!("drop_files_here")). The label may come from tr!(...) (translated) or lit!(...); it is stored as a LocalizedString and handed to the prompt’s TextWidget, so a tr!(...) label re-resolves on a locale switch without rebuilding the zone — the same model as Button::new.

pub fn subtitle(self, text: impl Into<LocalizedString>) -> Self

Secondary line under the prompt (e.g. tr!("png_or_jpeg")).

pub fn accept_extensions<I, S>(self, extensions: I) -> Self

where I: IntoIterator<Item = S>, S: Into<String>,

Restrict accepted files to these extensions (without leading dots, case-insensitive). Empty (the default) accepts any file. Text and URL drops are unaffected.

pub fn allow_multiple(self, allow: bool) -> Self

Whether more than one file may be dropped at once. Default true. When false, a multi-file drop is rejected.

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

Show or hide the keyboard-operable Browse button. Default true.

It is the zone’s only route that is not a drag. Turning it off leaves the drop as the sole way in, which fails WCAG 2.2 SC 2.5.7 (Dragging Movements) as well as SC 2.1.1 — so an application that hides it owes the same action another affordance of its own, reachable by keyboard and by a single pointer. See the non-drag alternatives page.

pub fn starting_dir(self, path: impl Into<PathBuf>) -> Self

Directory the Browse button’s dialog opens in. If unset, the OS default is used. Directory the Browse button’s dialog opens in. If unset, the OS default is used.

The same builder FilePickerField::starting_dir offers, and for the same reason: an app that remembers where its writer last picked files has no way to say so otherwise, because this widget builds its own FileDialogRequest internally rather than taking one.

pub fn browse_label(self, label: impl Into<LocalizedString>) -> Self

pub fn icon(self, icon: impl Widget + 'static) -> Self

An icon widget shown above the prompt (any widget — typically an IconWidget).

pub fn style(self, style: impl DropZoneStyle) -> Self

Override the Tier-3 DropZoneStyle for this instance only.

pub fn on_files_dropped( self, f: impl FnMut(Vec<PathBuf>, &mut EventContext<'_>) + 'static, ) -> Self

Called with the dropped (or browsed) file paths. Files are only accepted when this is set.

pub fn on_text_dropped( self, f: impl FnMut(String, &mut EventContext<'_>) + 'static, ) -> Self

Called with dropped plain text. Text drops are only accepted when set.

pub fn on_urls_dropped( self, f: impl FnMut(Vec<String>, &mut EventContext<'_>) + 'static, ) -> Self

Called with dropped non-file URLs. URL drops are only accepted when set.

Trait Implementations

impl Debug for DropZone

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

Formats the value using the given formatter.

impl Widget for DropZone

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

Position children within the allocated bounds.

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

Draw the widget’s visual representation.

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 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).