Struct EventCx 

pub struct EventCx<'a> { /* private fields */ }

What a widget gets while it handles an event (or is updated by the application through Ui::update): its state, and requests to the Ui.

Implementations

impl EventCx<'_>

pub fn id(&self) -> WidgetId

The widget handling the event.

pub fn rect(&self) -> Rect

Where the widget is, in physical pixels from the window’s top-left corner.

pub fn content_rect(&self) -> Rect

The widget’s rectangle inside its padding.

pub fn scroll(&self) -> Point

How far the widget’s children are scrolled.

pub fn content_size(&self) -> Size

The size of what the widget’s children cover.

pub fn is_hovered(&self) -> bool

Whether the pointer is over the widget or one of its children.

pub fn is_focused(&self) -> bool

Whether the widget has keyboard focus.

pub fn is_pressed(&self) -> bool

Whether the widget handled a pointer press that has not been released yet.

pub fn theme(&self) -> &Theme

The theme.

pub fn scale(&self) -> f32

Physical pixels per logical pixel.

pub fn px(&self, logical: f32) -> f32

logical pixels in physical pixels.

pub fn text_system(&mut self) -> &mut TextSystem

The text system, to edit and re-lay out text.

pub fn request_paint(&mut self)

Asks for the next frame to be painted.

pub fn clipboard(&mut self) -> &mut dyn Clipboard

The clipboard, to copy to and paste from.

pub fn request_layout(&mut self)

Asks for the widget to be measured again: its content changed size.

pub fn request_focus(&mut self)

Asks for keyboard focus, given once the event has been handled.

pub fn release_focus(&mut self)

Gives keyboard focus up, if the widget has it.

pub fn release_pointer(&mut self)

Stops receiving the pointer’s moves and release after a press.

pub fn set_cursor(&mut self, cursor: Option<Cursor>)

The cursor shown over the widget (and its children that set none); None for its parent’s.

pub fn set_ime_area(&mut self, area: Option<Rect>)

Where an input method should show its candidates while the widget has focus: the caret’s rectangle.

pub fn emit(&mut self, kind: ActionKind)

Reports kind to the application.

pub fn scroll_to(&mut self, offset: Point) -> Point

Scrolls the widget’s children by offset from their laid-out place, clamped so the content stays in view. Returns the offset applied.

pub fn children(&self) -> &[WidgetId]

The widget’s children, first painted first.

pub fn rect_of(&self, id: WidgetId) -> Option<Rect>

Where id is, if it is alive.

pub fn style_of(&self, id: WidgetId) -> Option<&Style>

The style of id, if it is alive.

pub fn focus_within(&self, id: WidgetId) -> bool

Whether keyboard focus is on id or a widget inside it.

pub fn set_style(&mut self, id: WidgetId, style: Style) -> bool

Changes the style of the widget itself or of a widget inside it (a splitter resizing its panes, tabs showing one page); false for any other widget.

impl EventCx<'_>

pub fn open_popup( &mut self, widget: impl Widget, anchor: Anchor, style: Style, ) -> Result<WidgetId, UiError>

Opens widget as a popup next to anchor, as Ui::open_popup does, with this widget as its opener: a press on this widget while the popup is open closes the popup and still reaches this widget. The popup joins the Ui once the event is handled.

Errors

UiError::TooManyWidgets.

pub fn close_popup(&mut self, id: WidgetId) -> bool

Closes popup id (this widget, say) and every popup opened after it, once the event is handled. false if id is not open.

pub fn close_popups(&mut self)

Closes every popup once the event is handled (a menu item was chosen).

pub fn is_popup_open(&self, id: WidgetId) -> bool

Whether id is an open popup.

Trait Implementations

impl<'a> Debug for EventCx<'a>

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

Formats the value using the given formatter.