use std::{path::Path, sync::Arc, time::Duration}; use anyhow::anyhow;use gpui::{    black, div, img, prelude::*, pulsating_between, px, red, size, Animation, AnimationExt, App,    AppContext, Asset, AssetLogger, AssetSource, Bounds, Hsla, ImageAssetLoader, ImageCacheError,    ImgResourceLoader, Length, Pixels, RenderImage, Resource, SharedString, ViewContext,    WindowBounds, WindowContext, WindowOptions, LOADING_DELAY,}; struct Assets {} impl AssetSource for Assets {    fn load(&self, path: &str) -> anyhow::Result<Option<std::borrow::Cow<'static, [u8]>>> {        std::fs::read(path)            .map(Into::into)            .map_err(Into::into)            .map(Some)    }     fn list(&self, path: &str) -> anyhow::Result<Vec<SharedString>> {        Ok(std::fs::read_dir(path)?            .filter_map(|entry| {                Some(SharedString::from(                    entry.ok()?.path().to_string_lossy().to_string(),                ))            })            .collect::<Vec<_>>())    }} const IMAGE: &str = "examples/image/app-icon.png"; #[derive(Copy, Clone, Hash)]struct LoadImageParameters {    timeout: Duration,    fail: bool,} struct LoadImageWithParameters {} impl Asset for LoadImageWithParameters {    type Source = LoadImageParameters;     type Output = Result<Arc<RenderImage>, ImageCacheError>;     fn load(        parameters: Self::Source,        cx: &mut AppContext,    ) -> impl std::future::Future<Output = Self::Output> + Send + 'static {        let timer = cx.background_executor().timer(parameters.timeout);        let data = AssetLogger::<ImageAssetLoader>::load(            Resource::Path(Path::new(IMAGE).to_path_buf().into()),            cx,        );        async move {            timer.await;            if parameters.fail {                log::error!("Intentionally failed to load image");                Err(anyhow!("Failed to load image").into())            } else {                data.await            }        }    }} struct ImageLoadingExample {} impl ImageLoadingExample {    fn loading_element() -> impl IntoElement {        div().size_full().flex_none().p_0p5().rounded_sm().child(            div().size_full().with_animation(                "loading-bg",                Animation::new(Duration::from_secs(3))                    .repeat()                    .with_easing(pulsating_between(0.04, 0.24)),                move |this, delta| this.bg(black().opacity(delta)),            ),        )    }     fn fallback_element() -> impl IntoElement {        let fallback_color: Hsla = black().opacity(0.5);         div().size_full().flex_none().p_0p5().child(            div()                .size_full()                .flex()                .items_center()                .justify_center()                .rounded_sm()                .text_sm()                .text_color(fallback_color)                .border_1()                .border_color(fallback_color)                .child("?"),        )    }} impl Render for ImageLoadingExample {    fn render(&mut self, _cx: &mut ViewContext<Self>) -> impl IntoElement {        div().flex().flex_col().size_full().justify_around().child(            div().flex().flex_row().w_full().justify_around().child(                div()                    .flex()                    .bg(gpui::white())                    .size(Length::Definite(Pixels(300.0).into()))                    .justify_center()                    .items_center()                    .child({                        let image_source = LoadImageParameters {                            timeout: LOADING_DELAY.saturating_sub(Duration::from_millis(25)),                            fail: false,                        };                         // Load within the 'loading delay', should not show loading fallback                        img(move |cx: &mut WindowContext| {                            cx.use_asset::<LoadImageWithParameters>(&image_source)                        })                        .id("image-1")                        .border_1()                        .size_12()                        .with_fallback(|| Self::fallback_element().into_any_element())                        .border_color(red())                        .with_loading(|| Self::loading_element().into_any_element())                        .on_click(move |_, cx| {                            cx.remove_asset::<LoadImageWithParameters>(&image_source);                        })                    })                    .child({                        // Load after a long delay                        let image_source = LoadImageParameters {                            timeout: Duration::from_secs(5),                            fail: false,                        };                         img(move |cx: &mut WindowContext| {                            cx.use_asset::<LoadImageWithParameters>(&image_source)                        })                        .id("image-2")                        .with_fallback(|| Self::fallback_element().into_any_element())                        .with_loading(|| Self::loading_element().into_any_element())                        .size_12()                        .border_1()                        .border_color(red())                        .on_click(move |_, cx| {                            cx.remove_asset::<LoadImageWithParameters>(&image_source);                        })                    })                    .child({                        // Fail to load image after a long delay                        let image_source = LoadImageParameters {                            timeout: Duration::from_secs(5),                            fail: true,                        };                         // Fail to load after a long delay                        img(move |cx: &mut WindowContext| {                            cx.use_asset::<LoadImageWithParameters>(&image_source)                        })                        .id("image-3")                        .with_fallback(|| Self::fallback_element().into_any_element())                        .with_loading(|| Self::loading_element().into_any_element())                        .size_12()                        .border_1()                        .border_color(red())                        .on_click(move |_, cx| {                            cx.remove_asset::<LoadImageWithParameters>(&image_source);                        })                    })                    .child({                        // Ensure that the normal image loader doesn't spam logs                        let image_source = Path::new(                            "this/file/really/shouldn't/exist/or/won't/be/an/image/I/hope",                        )                        .to_path_buf();                        img(image_source.clone())                            .id("image-1")                            .border_1()                            .size_12()                            .with_fallback(|| Self::fallback_element().into_any_element())                            .border_color(red())                            .with_loading(|| Self::loading_element().into_any_element())                            .on_click(move |_, cx| {                                cx.remove_asset::<ImgResourceLoader>(&image_source.clone().into());                            })                    }),            ),        )    }} fn main() {    env_logger::init();    App::new()        .with_assets(Assets {})        .run(|cx: &mut AppContext| {            let options = WindowOptions {                window_bounds: Some(WindowBounds::Windowed(Bounds::centered(                    None,                    size(px(300.), Pixels(300.)),                    cx,                ))),                ..Default::default()            };            cx.open_window(options, |cx| {                cx.activate(false);                cx.new_view(|_cx| ImageLoadingExample {})            })            .unwrap();        });}