Trait App 

pub trait App {
    // Required methods
    fn update(&mut self, msg: Message) -> Option<Command>;
    fn view(&self) -> String;

    // Provided method
    fn init(&self) -> Option<Command> { ... }
}

The trait your model must implement in order to be run.

init is called once when the model is run for the first time, and optionally returns a Command. There is a default implementation of init that returns None.

update is called every time your application recieves a Message. You are allowed to mutate your model’s state in this function. It optionally returns a Command.

view is called after every update and is responsible for rendering the model. It returns a String that is printed to the screen. You are not allowed to mutate the state of your application in the view, only render it.

For examples, check the examples directory.

Required Methods

fn update(&mut self, msg: Message) -> Option<Command>

fn view(&self) -> String

Provided Methods

fn init(&self) -> Option<Command>

Implementors