From fff333f89ba99f32171641f0e8d78c9cdfe291b4 Mon Sep 17 00:00:00 2001 From: Songtronix Date: Mon, 23 Mar 2020 15:54:23 +0100 Subject: [PATCH] Add example for download with progress tracking --- Cargo.toml | 1 + examples/download_progress/Cargo.toml | 13 +++ examples/download_progress/README.md | 15 +++ examples/download_progress/src/downloader.rs | 99 ++++++++++++++++ examples/download_progress/src/main.rs | 116 +++++++++++++++++++ 5 files changed, 244 insertions(+) create mode 100644 examples/download_progress/Cargo.toml create mode 100644 examples/download_progress/README.md create mode 100644 examples/download_progress/src/downloader.rs create mode 100644 examples/download_progress/src/main.rs diff --git a/Cargo.toml b/Cargo.toml index 12b75aed..d2444486 100644 --- a/Cargo.toml +++ b/Cargo.toml @@ -37,6 +37,7 @@ members = [ "web", "wgpu", "winit", + "examples/download_progress", "examples/bezier_tool", "examples/clock", "examples/counter", diff --git a/examples/download_progress/Cargo.toml b/examples/download_progress/Cargo.toml new file mode 100644 index 00000000..ce0435fd --- /dev/null +++ b/examples/download_progress/Cargo.toml @@ -0,0 +1,13 @@ +[package] +name = "download_progress" +version = "0.1.0" +authors = ["Songtronix "] +edition = "2018" +publish = false + +[dependencies] +iced = { path = "../.." } +iced_native = { path = "../../native" } +iced_futures = { path = "../../futures" } +async-std = { version = "1.0", features = ["unstable"] } +isahc = "0.9.1" diff --git a/examples/download_progress/README.md b/examples/download_progress/README.md new file mode 100644 index 00000000..c6311163 --- /dev/null +++ b/examples/download_progress/README.md @@ -0,0 +1,15 @@ +## Download Progress + +Downloading a file asynchronously with a `Subscription` while displaying the progress with a `ProgressBar`. + +
+ + + +
+ +You can run it with `cargo run`: + +``` +cargo run --package download_progress +``` diff --git a/examples/download_progress/src/downloader.rs b/examples/download_progress/src/downloader.rs new file mode 100644 index 00000000..62f943fd --- /dev/null +++ b/examples/download_progress/src/downloader.rs @@ -0,0 +1,99 @@ +use iced_futures::futures; + +// Just a little utility function +pub fn file(url: T) -> iced::Subscription { + iced::Subscription::from_recipe(Downloader { + url: url.to_string(), + }) +} + +pub struct Downloader { + url: String, +} + +// Make sure iced can use our download stream +impl iced_native::subscription::Recipe for Downloader +where + H: std::hash::Hasher, +{ + type Output = DownloadMessage; + + fn hash(&self, state: &mut H) { + use std::hash::Hash; + std::any::TypeId::of::().hash(state); + } + + fn stream( + self: Box, + _input: futures::stream::BoxStream<'static, I>, + ) -> futures::stream::BoxStream<'static, Self::Output> { + use isahc::prelude::*; + + Box::pin(futures::stream::unfold( + DownloadState::Ready(self.url), + |state| async move { + match state { + DownloadState::Ready(url) => { + let resp = Request::get(&url) + .metrics(true) + .body(()) + .unwrap() + .send_async() + .await + .unwrap(); + let metrics = resp.metrics().unwrap().clone(); + // If you actually want to download: + /*let file = async_std::fs::File::create("download.bin") + .await + .unwrap();*/ + + async_std::task::spawn(async_std::io::copy( + resp.into_body(), + async_std::io::sink(), //file + )); + + Some(( + DownloadMessage::DownloadStarted, + DownloadState::Downloading(metrics), + )) + } + DownloadState::Downloading(metrics) => { + async_std::task::sleep( + std::time::Duration::from_millis(100), + ) + .await; + + let percentage = metrics.download_progress().0 * 100 + / metrics.download_progress().1; + + if percentage == 100 { + Some(( + DownloadMessage::Done, + DownloadState::Finished, + )) + } else { + Some(( + DownloadMessage::Downloading(percentage), + DownloadState::Downloading(metrics), + )) + } + } + DownloadState::Finished => None, + } + }, + )) + } +} + +#[derive(Debug)] +pub enum DownloadMessage { + DownloadStarted, + Downloading(u64), + Done, +} + +pub enum DownloadState { + Ready(String), + Downloading(isahc::Metrics), + Finished, +} diff --git a/examples/download_progress/src/main.rs b/examples/download_progress/src/main.rs new file mode 100644 index 00000000..936144d5 --- /dev/null +++ b/examples/download_progress/src/main.rs @@ -0,0 +1,116 @@ +use iced::{ + button, executor, Align, Application, Button, Column, Command, Container, + Element, Length, ProgressBar, Settings, Subscription, Text, +}; + +mod downloader; + +pub fn main() { + Downloader::run(Settings::default()) +} + +#[derive(Debug, Default)] +struct Downloader { + // Whether to start the download or not. + enabled: bool, + // The current percentage of the download + current_progress: u64, + + btn_state: button::State, +} + +#[derive(Debug)] +pub enum Message { + DownloadUpdate(downloader::DownloadMessage), + Interaction(Interaction), +} + +// For explanation of why we use an Interaction enum see here: +// https://github.com/hecrj/iced/pull/155#issuecomment-573523405 +#[derive(Debug, Clone)] +pub enum Interaction { + // User pressed the button to start the download + StartDownload, +} + +impl Application for Downloader { + type Executor = executor::Default; + type Message = Message; + + fn new() -> (Downloader, Command) { + (Downloader::default(), Command::none()) + } + + fn title(&self) -> String { + String::from("Download Progress - Iced") + } + + fn update(&mut self, message: Message) -> Command { + match message { + Message::Interaction(action) => match action { + Interaction::StartDownload => { + self.enabled = true; + } + }, + Message::DownloadUpdate(update) => match update { + downloader::DownloadMessage::Downloading(percentage) => { + self.current_progress = percentage; + } + downloader::DownloadMessage::Done => { + self.current_progress = 100; + self.enabled = false; + } + _ => {} + }, + }; + + Command::none() + } + + fn subscription(&self) -> Subscription { + if self.enabled { + downloader::file("https://speed.hetzner.de/100MB.bin") + .map(Message::DownloadUpdate) + } else { + Subscription::none() + } + } + + fn view(&mut self) -> Element { + // Construct widgets + + let toggle_text = match self.enabled { + true => "Downloading...", + false => "Start the download!", + }; + + let toggle: Element = + Button::new(&mut self.btn_state, Text::new(toggle_text)) + .on_press(Interaction::StartDownload) + .into(); + + let progress_bar = + ProgressBar::new(0.0..=100.0, self.current_progress as f32); + + let progress_text = &match self.enabled { + true => format!("Downloading {}%", self.current_progress), + false => "Ready to rock!".into(), + }; + + // Construct layout + let content = Column::new() + .align_items(Align::Center) + .spacing(20) + .padding(20) + .push(Text::new(progress_text)) + .push(progress_bar) + .push(toggle.map(Message::Interaction)); + + Container::new(content) + .width(Length::Fill) + .height(Length::Fill) + .center_x() + .center_y() + .into() + } +}