use std::sync::Arc; use crate::{h_flex, prelude::*, Disclosure, Label};use gpui::{AnyElement, ClickEvent};use settings::Settings;use theme::ThemeSettings; #[derive(IntoElement)]pub struct ListHeader {    /// The label of the header.    label: SharedString,    /// A slot for content that appears before the label, like an icon or avatar.    start_slot: Option<AnyElement>,    /// A slot for content that appears after the label, usually on the other side of the header.    /// This might be a button, a disclosure arrow, a face pile, etc.    end_slot: Option<AnyElement>,    /// A slot for content that appears on hover after the label    /// It will obscure the `end_slot` when visible.    end_hover_slot: Option<AnyElement>,    toggle: Option<bool>,    on_toggle: Option<Arc<dyn Fn(&ClickEvent, &mut Window, &mut App) + 'static>>,    inset: bool,    selected: bool,} impl ListHeader {    pub fn new(label: impl Into<SharedString>) -> Self {        Self {            label: label.into(),            start_slot: None,            end_slot: None,            end_hover_slot: None,            inset: false,            toggle: None,            on_toggle: None,            selected: false,        }    }     pub fn toggle(mut self, toggle: impl Into<Option<bool>>) -> Self {        self.toggle = toggle.into();        self    }     pub fn on_toggle(        mut self,        on_toggle: impl Fn(&ClickEvent, &mut Window, &mut App) + 'static,    ) -> Self {        self.on_toggle = Some(Arc::new(on_toggle));        self    }     pub fn start_slot<E: IntoElement>(mut self, start_slot: impl Into<Option<E>>) -> Self {        self.start_slot = start_slot.into().map(IntoElement::into_any_element);        self    }     pub fn end_slot<E: IntoElement>(mut self, end_slot: impl Into<Option<E>>) -> Self {        self.end_slot = end_slot.into().map(IntoElement::into_any_element);        self    }     pub fn end_hover_slot<E: IntoElement>(mut self, end_hover_slot: impl Into<Option<E>>) -> Self {        self.end_hover_slot = end_hover_slot.into().map(IntoElement::into_any_element);        self    }     pub fn inset(mut self, inset: bool) -> Self {        self.inset = inset;        self    }} impl Toggleable for ListHeader {    fn toggle_state(mut self, selected: bool) -> Self {        self.selected = selected;        self    }} impl RenderOnce for ListHeader {    fn render(self, _window: &mut Window, cx: &mut App) -> impl IntoElement {        let ui_density = ThemeSettings::get_global(cx).ui_density;         h_flex()            .id(self.label.clone())            .w_full()            .relative()            .group("list_header")            .child(                div()                    .map(|this| match ui_density {                        theme::UiDensity::Comfortable => this.h_5(),                        _ => this.h_7(),                    })                    .when(self.inset, |this| this.px_2())                    .when(self.selected, |this| {                        this.bg(cx.theme().colors().ghost_element_selected)                    })                    .flex()                    .flex_1()                    .items_center()                    .justify_between()                    .w_full()                    .gap(DynamicSpacing::Base04.rems(cx))                    .child(                        h_flex()                            .gap(DynamicSpacing::Base04.rems(cx))                            .children(self.toggle.map(|is_open| {                                Disclosure::new("toggle", is_open).on_toggle(self.on_toggle.clone())                            }))                            .child(                                div()                                    .id("label_container")                                    .flex()                                    .gap(DynamicSpacing::Base04.rems(cx))                                    .items_center()                                    .children(self.start_slot)                                    .child(Label::new(self.label.clone()).color(Color::Muted))                                    .when_some(self.on_toggle, |this, on_toggle| {                                        this.on_click(move |event, window, cx| {                                            on_toggle(event, window, cx)                                        })                                    }),                            ),                    )                    .child(h_flex().children(self.end_slot))                    .when_some(self.end_hover_slot, |this, end_hover_slot| {                        this.child(                            div()                                .absolute()                                .right_0()                                .visible_on_hover("list_header")                                .child(end_hover_slot),                        )                    }),            )    }}