Enum EitherOf3 

pub enum EitherOf3<A, B, C> {
    A(A),
    B(B),
    C(C),
}

Pick one of three view types from a match while keeping every arm statically typed (no AnyView erasure).

use frust_core::View;
use frust_widgets::{EitherOf3, button, checkbox, text};

enum Phase {
    Idle,
    Busy,
    Done,
}

struct Screen;

impl Screen {
    fn body(phase: Phase) -> impl View<()> {
        match phase {
            Phase::Idle => EitherOf3::A(text("Idle")),
            Phase::Busy => EitherOf3::B(button::<(), _>("Cancel", |_| {})),
            Phase::Done => EitherOf3::C(checkbox::<(), _>(true, "Ok", |_, _| {})),
        }
    }
}

let _ = Screen::body(Phase::Idle);
let _ = Screen::body(Phase::Busy);
let _ = Screen::body(Phase::Done);

A view that is one of three statically-typed arms. Arm swaps behave as for Either: the old arm is torn down, the new one built fresh, and LAYOUT | PAINT is reported. See the module docs.

Variants

A(A)

Arm A.

B(B)

Arm B.

C(C)

Arm C.

Trait Implementations

impl<State, A, B, C> View<State> for EitherOf3<A, B, C>

where State: 'static, A: View<State>, B: View<State>, C: View<State>,

type Element = EitherOf3Widget<<A as View<State>>::Element, <B as View<State>>::Element, <C as View<State>>::Element>

The retained widget this view produces.

fn build( &self, ctx: &mut BuildCtx<'_>, ) -> <EitherOf3<A, B, C> as View<State>>::Element

Materialise a fresh widget for this view.

fn rebuild( &self, prev: &EitherOf3<A, B, C>, element: &mut <EitherOf3<A, B, C> as View<State>>::Element, ctx: &mut BuildCtx<'_>, ) -> ChangeFlags

Reconcile prev (the previous view of the same type) against the live element, mutating it in place and reporting what changed.

fn teardown( &self, element: &mut <EitherOf3<A, B, C> as View<State>>::Element, ctx: &mut BuildCtx<'_>, )

Tear down element when this view is being removed.

fn message( &self, element: &mut <EitherOf3<A, B, C> as View<State>>::Element, state: &mut State, )

Deliver an event message to this view, mutating application state.