winio 0.5.1

# Winio

Winio is a single-threaded asynchronous GUI runtime.
It is based on [`compio`](https://github.com/compio-rs/compio), and the GUI part is powered by Win32, Qt, GTK and Cocoa.
All IO requests could be issued in the same thread as GUI, without blocking the user interface!

## Quick start

Winio follows ELM-like design, inspired by [`yew`](https://yew.rs/) and [`relm4`](https://relm4.org/).
The application starts with a root `Component`:

```rust
use winio::{
    App, Child, Component, ComponentSender, Layoutable, Size, Visible, Window, WindowEvent,
};

fn main() {
    App::new().run::<MainModel>(());
}

struct MainModel {
    window: Child<Window>,
}

enum MainMessage {
    Noop,
    Close,
}

impl Component for MainModel {
    type Event = ();
    type Init<'a> = ();
    type Message = MainMessage;

    fn init(_init: Self::Init<'_>, _sender: &ComponentSender<Self>) -> Self {
        // create & initialize the window
        let mut window = Child::<Window>::init(());
        window.set_text("Basic example");
        window.set_size(Size::new(800.0, 600.0));
        window.show();
        Self { window }
    }

    async fn start(&mut self, sender: &ComponentSender<Self>) {
        // listen to events
        self.window
            .start(
                sender,
                |e| match e {
                    WindowEvent::Close => Some(MainMessage::Close),
                    _ => None,
                },
                || MainMessage::Noop,
            )
            .await;
    }

    async fn update(&mut self, message: Self::Message, sender: &ComponentSender<Self>) -> bool {
        // update the window
        self.window.update().await;
        // deal with custom messages
        match message {
            MainMessage::Noop => false,
            MainMessage::Close => {
                // the root component output stops the application
                sender.output(());
                // need not to call `render`
                false
            }
        }
    }

    fn render(&mut self, _sender: &ComponentSender<Self>) {
        // adjust layout and draw widgets here
    }
}
```