<div align="center">
<img src="docs/logo.svg" width="140px" />
# Iced
[][documentation]
[](https://crates.io/crates/iced)
[](https://github.com/iced-rs/iced/blob/master/LICENSE)
[](https://crates.io/crates/iced)
[](https://github.com/iced-rs/iced/actions)
[](https://discourse.iced.rs/)
[](https://discord.gg/3xZJ65GAhd)
A cross-platform GUI library for Rust focused on simplicity and type-safety.
Inspired by [Elm].
<a href="https://github.com/squidowl/halloy">
<img src="https://iced.rs/showcase/halloy.gif" width="460px">
</a>
<a href="https://github.com/hecrj/icebreaker">
<img src="https://iced.rs/showcase/icebreaker.gif" width="360px">
</a>
</div>
## Features
* Simple, easy-to-use, batteries-included API
* Type-safe, reactive programming model
* [Cross-platform support] (Windows, macOS, Linux, and the Web)
* Responsive layout
* Built-in widgets (including [text inputs], [scrollables], and more!)
* Custom widget support (create your own!)
* [Debug overlay with performance metrics]
* First-class support for async actions (use futures!)
* Modular ecosystem split into reusable parts:
* A [renderer-agnostic native runtime] enabling integration with existing systems
* Two built-in renderers leveraging [`wgpu`] and [`tiny-skia`]
* [`iced_wgpu`] supporting Vulkan, Metal and DX12
* [`iced_tiny_skia`] offering a software alternative as a fallback
* A [windowing shell]
__Iced is currently experimental software.__ [Take a look at the roadmap] and
[check out the issues].
[Cross-platform support]: https://raw.githubusercontent.com/iced-rs/iced/master/docs/images/todos_desktop.jpg
[text inputs]: https://iced.rs/examples/text_input.mp4
[scrollables]: https://iced.rs/examples/scrollable.mp4
[Debug overlay with performance metrics]: https://iced.rs/examples/debug.mp4
[renderer-agnostic native runtime]: runtime/
[`wgpu`]: https://github.com/gfx-rs/wgpu
[`tiny-skia`]: https://github.com/RazrFalcon/tiny-skia
[`iced_wgpu`]: wgpu/
[`iced_tiny_skia`]: tiny_skia/
[windowing shell]: winit/
[Take a look at the roadmap]: ROADMAP.md
[check out the issues]: https://github.com/iced-rs/iced/issues
## Overview
Inspired by [The Elm Architecture], Iced expects you to split user interfaces
into four different concepts:
* __State__ — the state of your application
* __Messages__ — user interactions or meaningful events that you care
about
* __View logic__ — a way to display your __state__ as widgets that
may produce __messages__ on user interaction
* __Update logic__ — a way to react to __messages__ and update your
__state__
We can build something to see how this works! Let's say we want a simple counter
that can be incremented and decremented using two buttons.
We start by modelling the __state__ of our application:
```rust
#[derive(Default)]
struct Counter {
value: i32,
}
```
Next, we need to define the possible user interactions of our counter:
the button presses. These interactions are our __messages__:
```rust
#[derive(Debug, Clone, Copy)]
pub enum Message {
Increment,
Decrement,
}
```
Now, let's show the actual counter by putting it all together in our
__view logic__:
```rust
use iced::widget::{button, column, text, Column};
impl Counter {
pub fn view(&self) -> Column<Message> {
// We use a column: a simple vertical layout
column![
// The increment button. We tell it to produce an
// `Increment` message when pressed
button("+").on_press(Message::Increment),
// We show the value of the counter here
text(self.value).size(50),
// The decrement button. We tell it to produce a
// `Decrement` message when pressed
button("-").on_press(Message::Decrement),
]
}
}
```
Finally, we need to be able to react to any produced __messages__ and change our
__state__ accordingly in our __update logic__:
```rust
impl Counter {
// ...
pub fn update(&mut self, message: Message) {
match message {
Message::Increment => {
self.value += 1;
}
Message::Decrement => {
self.value -= 1;
}
}
}
}
```
And that's everything! We just wrote a whole user interface. Let's run it:
```rust
fn main() -> iced::Result {
iced::run("A cool counter", Counter::update, Counter::view)
}
```
Iced will automatically:
1. Take the result of our __view logic__ and layout its widgets.
1. Process events from our system and produce __messages__ for our
__update logic__.
1. Draw the resulting user interface.
Read the [book], the [documentation], and the [examples] to learn more!
## Implementation details
Iced was originally born as an attempt at bringing the simplicity of [Elm] and
[The Elm Architecture] into [Coffee], a 2D game library I am working on.
The core of the library was implemented during May 2019 in [this pull request].
[The first alpha version] was eventually released as
[a renderer-agnostic GUI library]. The library did not provide a renderer and
implemented the current [tour example] on top of [`ggez`], a game library.
Since then, the focus has shifted towards providing a batteries-included,
end-user-oriented GUI library, while keeping the ecosystem modular.
[this pull request]: https://github.com/hecrj/coffee/pull/35
[The first alpha version]: https://github.com/iced-rs/iced/tree/0.1.0-alpha
[a renderer-agnostic GUI library]: https://www.reddit.com/r/rust/comments/czzjnv/iced_a_rendereragnostic_gui_library_focused_on/
[tour example]: examples/README.md#tour
[`ggez`]: https://github.com/ggez/ggez
## Contributing / Feedback
If you want to contribute, please read our [contributing guidelines] for more details.
Feedback is also welcome! You can create a new topic in [our Discourse forum] or
come chat to [our Discord server].
## Sponsors
The development of Iced is sponsored by the [Cryptowatch] team at [Kraken.com]
[book]: https://book.iced.rs/
[documentation]: https://docs.rs/iced/
[examples]: https://github.com/iced-rs/iced/tree/master/examples#examples
[Coffee]: https://github.com/hecrj/coffee
[Elm]: https://elm-lang.org/
[The Elm Architecture]: https://guide.elm-lang.org/architecture/
[the current issues]: https://github.com/iced-rs/iced/issues
[contributing guidelines]: https://github.com/iced-rs/iced/blob/master/CONTRIBUTING.md
[our Discourse forum]: https://discourse.iced.rs/
[our Discord server]: https://discord.gg/3xZJ65GAhd
[Cryptowatch]: https://cryptowat.ch/charts
[Kraken.com]: https://kraken.com/
