Struct TreeAppContext 

pub struct TreeAppContext { /* private fields */ }

Per-tree app-level subscription state.

Held by WidgetTree as Rc<TreeAppContext> so that BuildContext can reach the event source adapter, allocate subscription ids, and post the UI-side callback into the lookup map. Fields are RefCell/Cell because the tree borrows itself mutably during build() and we need shared interior access.

Implementations

impl TreeAppContext

pub fn empty() -> Self

Empty context — no event source, no proxy poster. Used by tests and by WidgetTree::new().

pub fn with_source_and_poster( event_source: EventSourceAdapter, poster: Arc<dyn AppEventPoster>, ) -> Self

Build a context with both a registered event source and a proxy poster. Called by teksilo-app when constructing a window for an application that registered an event source on the builder.

pub fn with_app_state(self, registry: HashMap<TypeId, Box<dyn Any>>) -> Self

Install an app-state registry. Consumes self and returns a new context with the registry attached; the builder calls this after constructing the context and before wrapping it in Rc.

pub fn with_poster(self, poster: Arc<dyn AppEventPoster>) -> Self

Install an AppEventPoster so background work (file dialogs, future async-result features) can post typed payloads back to the UI loop via AppEvent::External. The builder calls this unconditionally during TeksiloAppBuilder::run — the poster is cheap (a thin wrapper around the event-loop proxy) and being reachable means widgets do not have to depend on the event-source feature for unrelated async-result delivery.

pub fn poster(&self) -> Option<&Arc<dyn AppEventPoster>>

Borrow the registered AppEventPoster if one was installed. Used by integrations that need to post typed payloads back to the UI loop from an external thread (e.g. file-dialog backends).

pub fn app_state<T: 'static>(&self) -> Option<&T>

Look up an app-state value of type T previously registered via TeksiloAppBuilder::app_state.

pub fn dispatch_subscription_event( &self, sub_id: SubscriptionId, event: &dyn Any, ) -> bool

Look up and invoke the UI-side callback for a posted subscription event. Returns true if a callback was found and invoked.

pub fn ctx_subscription_window( &self, sub_id: SubscriptionId, ) -> Option<TeksiloWindowId>

The window a context-bearing subscription targets, if sub_id names one and it was registered from a window (always true in a real app). teksilo-app peeks this to know which window’s tree to mint the EventContext from before dispatching.

pub fn dispatch_subscription_event_with_ctx( &self, sub_id: SubscriptionId, event: &dyn Any, ctx: &mut EventContext<'_>, ) -> bool

Invoke the context-bearing UI-side callback for a posted subscription event, passing the freshly-minted EventContext. Returns true if a callback was found and invoked. Called by teksilo-app from inside WidgetTree::run_with_event_context.

The Rc handle is cloned and the map borrow released before the call, so the callback may freely re-enter this map — e.g. ctx.open_window(...) synchronously builds a new tree whose widgets register their own context-bearing subscriptions. (Holding the borrow across the call would panic there; hence Rc, not Box.)

pub fn ctx_subscription_count(&self) -> usize

Number of context-bearing subscription callbacks currently installed. Companion to subscription_count; used by lifecycle tests to assert the ctx-map teardown ran.

pub fn purge_ctx_subscriptions_for_window(&self, window_id: TeksiloWindowId)

Drop every context-bearing subscription targeting window_id. Called by teksilo-app when a window closes, so the shared, longer-lived TreeAppContext map doesn’t retain inert callbacks for a torn-down tree (a window’s tree is dropped without a per-widget destroy_subtree pass). Mirrors AsyncCompletionHandle::purge_window.

pub fn subscription_count(&self) -> usize

Number of UI-side subscription callbacks currently installed. Used by lifecycle tests to assert cleanup ran correctly.