//! A container query element, in the spirit of CSS container queries.//! The element's own size is determined solely by its style and the space//! offered by its parent. use refineable::Refineable as _; use crate::{    AnyElement, App, AvailableSpace, Bounds, Element, ElementId, GlobalElementId,    InspectorElementId, IntoElement, LayoutId, Pixels, Size, Style, StyleRefinement, Styled,    Window, relative,}; /// Construct a container query element with the given render callback./// The callback receives the size the element was assigned during layout and/// returns the contents to display within it.////// By default the element fills its parent (equivalent to `.size_full()`);/// use the [`Styled`] methods to size it differently. Because the contents/// don't exist until after layout, they cannot influence the element's size.////// # Example////// ```/// # use gpui::{container_query, div, px, IntoElement, ParentElement};/// container_query(|size, _window, _cx| {///     if size.width < px(240.) {///         div().child("Narrow layout")///     } else {///         div().child("Wide layout")///     }/// });/// ```pub fn container_query<E>(    render: impl 'static + FnOnce(Size<Pixels>, &mut Window, &mut App) -> E,) -> ContainerQuerywhere    E: IntoElement,{    let mut base_style = StyleRefinement::default();    base_style.size.width = Some(relative(1.).into());    base_style.size.height = Some(relative(1.).into());     ContainerQuery {        render: Some(Box::new(|size, window, cx| {            render(size, window, cx).into_any_element()        })),        style: base_style,    }} /// A container query element, created with [`container_query`].pub struct ContainerQuery {    render: Option<Box<dyn FnOnce(Size<Pixels>, &mut Window, &mut App) -> AnyElement>>,    style: StyleRefinement,} impl Element for ContainerQuery {    type RequestLayoutState = ();    type PrepaintState = Option<AnyElement>;     fn id(&self) -> Option<ElementId> {        None    }     fn source_location(&self) -> Option<&'static core::panic::Location<'static>> {        None    }     fn request_layout(        &mut self,        _id: Option<&GlobalElementId>,        _inspector_id: Option<&InspectorElementId>,        window: &mut Window,        cx: &mut App,    ) -> (LayoutId, Self::RequestLayoutState) {        let mut style = Style::default();        style.refine(&self.style);        let layout_id = window.request_layout(style, [], cx);        (layout_id, ())    }     fn prepaint(        &mut self,        _id: Option<&GlobalElementId>,        _inspector_id: Option<&InspectorElementId>,        bounds: Bounds<Pixels>,        _request_layout: &mut Self::RequestLayoutState,        window: &mut Window,        cx: &mut App,    ) -> Option<AnyElement> {        let render = self.render.take()?;        let mut child = render(bounds.size, window, cx);        child.layout_as_root(bounds.size.map(AvailableSpace::Definite), window, cx);        child.prepaint_at(bounds.origin, window, cx);        Some(child)    }     fn paint(        &mut self,        _id: Option<&GlobalElementId>,        _inspector_id: Option<&InspectorElementId>,        _bounds: Bounds<Pixels>,        _request_layout: &mut Self::RequestLayoutState,        prepaint: &mut Self::PrepaintState,        window: &mut Window,        cx: &mut App,    ) {        if let Some(child) = prepaint {            child.paint(window, cx);        }    }} impl IntoElement for ContainerQuery {    type Element = Self;     fn into_element(self) -> Self::Element {        self    }} impl Styled for ContainerQuery {    fn style(&mut self) -> &mut StyleRefinement {        &mut self.style    }}