winit 0.20.0-alpha4

# winit - Cross-platform window creation and management in Rust

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```toml
[dependencies]
winit = "0.20.0-alpha4"
```

## [Documentation](https://docs.rs/winit)

For features _within_ the scope of winit, see [FEATURES.md](FEATURES.md).

For features _outside_ the scope of winit, see [Missing features provided by other crates](https://github.com/rust-windowing/winit/wiki/Missing-features-provided-by-other-crates) in the wiki.

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## Usage

Winit is a window creation and management library. It can create windows and lets you handle
events (for example: the window being resized, a key being pressed, a mouse movement, etc.)
produced by window.

Winit is designed to be a low-level brick in a hierarchy of libraries. Consequently, in order to
show something on the window you need to use the platform-specific getters provided by winit, or
another library.

```rust
use winit::{
    event::{Event, WindowEvent},
    event_loop::{ControlFlow, EventLoop},
    window::WindowBuilder,
};

fn main() {
    let event_loop = EventLoop::new();
    let window = WindowBuilder::new().build(&event_loop).unwrap();

    event_loop.run(move |event, _, control_flow| {
        match event {
            Event::WindowEvent {
                event: WindowEvent::CloseRequested,
                window_id,
            } if window_id == window.id() => *control_flow = ControlFlow::Exit,
            _ => *control_flow = ControlFlow::Wait,
        }
    });
}
```

Winit is only officially supported on the latest stable version of the Rust compiler.

### Cargo Features

Winit provides the following features, which can be enabled in your `Cargo.toml` file:
* `serde`: Enables serialization/deserialization of certain types with [Serde](https://crates.io/crates/serde).

### Platform-specific usage

#### WebAssembly

Building a binary will yield a `.js` file. In order to use it in an HTML file, you need to:

- Put a `<canvas id="my_id"></canvas>` element somewhere. A canvas corresponds to a winit "window".
- Write a Javascript code that creates a global variable named `Module`. Set `Module.canvas` to
  the element of the `<canvas>` element (in the example you would retrieve it via `document.getElementById("my_id")`).
  More information [here](https://kripken.github.io/emscripten-site/docs/api_reference/module.html).
- Make sure that you insert the `.js` file generated by Rust after the `Module` variable is created.