Trait Component 

pub trait Component:
    Send
    + Sync
    + 'static {
    // Required method
    fn build(&self, ctx: &mut Context) -> Element;

    // Provided methods
    fn on_mount(&self) { ... }
    fn on_unmount(&self) { ... }
    fn type_name(&self) -> &'static str { ... }
    fn into_element(self) -> Element
       where Self: Sized { ... }
}

The core trait every ROSACE component implements.

A component is a pure function from props (&self) and Context to an Element tree. The framework calls build every frame (Phase 1) or when the component is marked dirty by a state change (Phase 2+).

Example

struct Greeting { name: String }

impl Component for Greeting {
    fn build(&self, ctx: &mut Context) -> Element {
        Text::new(format!("Hello, {}!", self.name)).into_element()
    }
}

Required Methods

fn build(&self, ctx: &mut Context) -> Element

Produce the element tree for this component.

Provided Methods

fn on_mount(&self)

Called once after the component first appears in the tree.

Default implementation is a no-op. Override for side effects that should run on mount (e.g., starting timers, subscriptions).

fn on_unmount(&self)

Called once after the component is removed from the tree.

Default implementation is a no-op. Override for cleanup that cannot be expressed as a ctx.on_cleanup closure (e.g., releasing platform resources held by self).

fn type_name(&self) -> &'static str

Fully-qualified type name used in diagnostics.

fn into_element(self) -> Element

where Self: Sized,

Convert this component into an Element so it can be embedded inside another component’s build() output.

The reconciler assigns the real position-based ComponentId during the tree walk; ComponentId(0) here is a placeholder.

Dyn Compatibility

This trait is dyn compatible.

In older versions of Rust, dyn compatibility was called "object safety".

Implementors