Input, actions, and focus

Events

Handlers are registered on elements:

div().on_click(cx.listener(|this: &mut Self, event, window, cx| {
    this.clicked += 1;
    cx.notify();
}))

cx.listener binds a handler to the current entity, giving it &mut Self and a Context<Self> when it fires.

Actions

Actions are named commands that can be bound to keys or dispatched from code.

actions!(card, [Expand, Collapse]);

div()
    .key_context("Card")
    .on_action(cx.listener(|this, _: &Expand, _window, cx| {
        this.expanded = true;
        cx.notify();
    }))

Dispatch from code with window.dispatch_action(Expand.boxed_clone(), cx) or focus_handle.dispatch_action(&Expand, window, cx). Actions with data use the Action derive macro. Doc comments on actions are user-visible text.

Focus and dispatch

Key events travel along the focus path, from the focused element up to the window root, and each element’s key_context decides which bindings apply. Zed’s Key dispatch chapter has the full model.