Collapse

Collapse — a wrapper widget that animates its child between hidden and natural size when an external Signal<bool> toggles.

Public functions

Collapse

Detailed description

Drives a progress: Signal<f32> ∈ [0, 1] (0 = collapsed, 1 = expanded) and reports its own size as (natural_w, natural_h * progress) while the child lays out at full natural size — the framework's clip pass crops the overflow. This keeps the animation visible across the whole duration, instead of compressing the visible portion into the final few milliseconds (which is what happened when an animated MaxSize::max_height slid against a 10000-px sentinel that vastly overshot the child's natural height).

let expanded = ctx.signal(false);
ctx.add(Collapse::new(expanded.clone()).child(advanced_settings));
// ...elsewhere:
expanded.set(true);  // animates open over `motion.duration_collapse`

Honors prefers-reduced-motion: under reduced motion, progress snaps to its end value instead of tweening.

API reference

📖 Full rustdoc API for this module

pub struct Collapse

Import: use teksilo::widgets::Collapse;

Wraps a child and animates it between hidden (progress=0) and natural size (progress=1), driven by an external Signal<bool>.

#![allow(unused)]
fn main() {
pub struct Collapse { /* fields */ }
}

Methods

pub fn new(expanded: Signal<bool>) -> Self

Build a collapse wrapper bound to expanded. Initially collapsed iff expanded.get() is false at the first build().

pub fn child(mut self, widget: impl teksilo_core::IntoTeksiChild) -> Self

Inline child widget (deferred insertion).

pub fn child_opt(self, widget: Option<impl teksilo_core::IntoTeksiChild>) -> Self

Attach widget when it is Some, and do nothing when it is None.

The conditional-child form. teksu!'s if without an else lowers to this, and it is what cond.then(|| w) is for in a builder chain. None adds no arena node, so nothing is laid out, painted, or published to the accessibility tree, and a stack applies no spacing around it.