Struct Radio

pub struct Radio<Msg: Clone> { /* private fields */ }

One option inside a mutually-exclusive group.

Renders a circle with a centred dot when selected. Unlike Checkbox, a radio is meaningful only as part of a group: the group is the application’s responsibility — define an enum for the choices, store the current value, and build one Radio per variant with selected = current == this_variant.

#[ derive( Clone, PartialEq ) ]
enum Priority { Low, Medium, High }
// In view():
column()
    .push( radio( self.priority == Priority::Low    ).label( "Low"    ).on_select( Msg::SetPriority( Priority::Low    ) ) )
    .push( radio( self.priority == Priority::Medium ).label( "Medium" ).on_select( Msg::SetPriority( Priority::Medium ) ) )
    .push( radio( self.priority == Priority::High   ).label( "High"   ).on_select( Msg::SetPriority( Priority::High   ) ) )
.into()

ltk does not enforce mutual exclusion automatically; the application’s update decides which variant becomes active when a radio is selected.

Implementations

impl<Msg: Clone> Radio<Msg>

pub fn new(selected: bool) -> Self

Create a radio in the given state, with no label and no callback.

pub fn on_select(self, msg: Msg) -> Self

Set the message emitted when this option is picked. The application’s update is responsible for flipping the group’s current value.

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

Set a text label rendered to the right of the circle.

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

Assign a stable identifier for focus management.

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

Override the preferred height (default: the theme row height, theme::HEIGHT design px). Accepts any Length so dense layouts can tie the row height to the viewport. The resolved value is floored at the outer circle size so the ring never clips; the circle keeps its theme size and stays centred.

pub fn preferred_size(&self, max_width: f32, canvas: &Canvas) -> (f32, f32)

pub fn paint_bounds(&self, rect: Rect) -> Rect

Focus ring on the outer circle extends FOCUS_W + 2 + FOCUS_W/2 ≈ 6.5 px beyond the circle (which sits flush with the widget’s left edge).

pub fn draw(&self, canvas: &mut Canvas, rect: Rect, focused: bool)

Trait Implementations

impl<Msg: Clone + 'static> From<Radio<Msg>> for Element<Msg>

fn from(r: Radio<Msg>) -> Self

Converts to this type from the input type.