Write docs for iced and iced_native

src/sandbox.rs

@@ -1,16 +1,126 @@
 use crate::{Application, Command, Element};
 
+/// A sandboxed [`Application`].
+///
+/// A [`Sandbox`] is just an [`Application`] that cannot run any asynchronous
+/// actions.
+///
+/// If you do not need to leverage a [`Command`], you can use a [`Sandbox`]
+/// instead of returning a [`Command::none`] everywhere.
+///
+/// [`Application`]: trait.Application.html
+/// [`Sandbox`]: trait.Sandbox.html
+/// [`Command`]: struct.Command.html
+/// [`Command::none`]: struct.Command.html#method.none
+///
+/// # Example
+/// We can use a [`Sandbox`] to run the [`Counter` example we implemented
+/// before](index.html#overview), instead of an [`Application`]. We just need
+/// to remove the use of [`Command`]:
+///
+/// ```no_run
+/// use iced::{button, Button, Column, Element, Sandbox, Text};
+///
+/// pub fn main() {
+///     Counter::run()
+/// }
+///
+/// #[derive(Default)]
+/// struct Counter {
+///     value: i32,
+///     increment_button: button::State,
+///     decrement_button: button::State,
+/// }
+///
+/// #[derive(Debug, Clone, Copy)]
+/// enum Message {
+///     IncrementPressed,
+///     DecrementPressed,
+/// }
+///
+/// impl Sandbox for Counter {
+///     type Message = Message;
+///
+///     fn new() -> Self {
+///         Self::default()
+///     }
+///
+///     fn title(&self) -> String {
+///         String::from("A simple counter")
+///     }
+///
+///     fn update(&mut self, message: Message) {
+///         match message {
+///             Message::IncrementPressed => {
+///                 self.value += 1;
+///             }
+///             Message::DecrementPressed => {
+///                 self.value -= 1;
+///             }
+///         }
+///     }
+///
+///     fn view(&mut self) -> Element<Message> {
+///         Column::new()
+///             .push(
+///                 Button::new(&mut self.increment_button, Text::new("Increment"))
+///                     .on_press(Message::IncrementPressed),
+///             )
+///             .push(
+///                 Text::new(self.value.to_string()).size(50),
+///             )
+///             .push(
+///                 Button::new(&mut self.decrement_button, Text::new("Decrement"))
+///                     .on_press(Message::DecrementPressed),
+///             )
+///             .into()
+///     }
+/// }
+/// ```
 pub trait Sandbox {
+    /// The type of __messages__ your [`Sandbox`] will produce.
+    ///
+    /// [`Sandbox`]: trait.Sandbox.html
     type Message: std::fmt::Debug + Send;
 
+    /// Initializes the [`Sandbox`].
+    ///
+    /// Here is where you should return the initial state of your app.
+    ///
+    /// [`Sandbox`]: trait.Sandbox.html
     fn new() -> Self;
 
+    /// Returns the current title of the [`Sandbox`].
+    ///
+    /// This title can be dynamic! The runtime will automatically update the
+    /// title of your application when necessary.
+    ///
+    /// [`Sandbox`]: trait.Sandbox.html
     fn title(&self) -> String;
 
+    /// Handles a __message__ and updates the state of the [`Sandbox`].
+    ///
+    /// This is where you define your __update logic__. All the __messages__,
+    /// produced by user interactions, will be handled by this method.
+    ///
+    /// [`Sandbox`]: trait.Sandbox.html
     fn update(&mut self, message: Self::Message);
 
-    fn view(&mut self) -> Element<Self::Message>;
+    /// Returns the widgets to display in the [`Sandbox`].
+    ///
+    /// These widgets can produce __messages__ based on user interaction.
+    ///
+    /// [`Sandbox`]: trait.Sandbox.html
+    fn view(&mut self) -> Element<'_, Self::Message>;
 
+    /// Runs the [`Sandbox`].
+    ///
+    /// This method will take control of the current thread and __will NOT
+    /// return__.
+    ///
+    /// It should probably be that last thing you call in your `main` function.
+    ///
+    /// [`Sandbox`]: trait.Sandbox.html
     fn run()
     where
         Self: 'static + Sized,
@@ -39,7 +149,7 @@ where
         Command::none()
     }
 
-    fn view(&mut self) -> Element<T::Message> {
+    fn view(&mut self) -> Element<'_, T::Message> {
         T::view(self)
     }
 }