Trait ViewEmbedder 

pub trait ViewEmbedder {
    // Required methods
    fn add_view(
        &self,
        layer: &Arc<dyn CompositionLayer>,
        metrics: ViewMetrics,
        host: Rc<dyn ViewHost>,
    ) -> Result<RequestId, ViewError>;
    fn set_view_metrics(&self, view: ViewId, metrics: ViewMetrics);
    fn set_view_in_sight(&self, view: ViewId, in_sight: bool);
    fn remove_view(&self, view: ViewId);
    fn send_pointer_reports(&self, reports: Vec<PointerReport>);
    fn send_view_focus_event(&self, event: ViewFocusEvent);
}

What the app uses to embed views of its own, as Flutter’s embedder does: adding one on a layer it makes and places, giving its metrics and its being in sight, handing it input, and removing it (Platform::view_embedder).

Required Methods

fn add_view( &self, layer: &Arc<dyn CompositionLayer>, metrics: ViewMetrics, host: Rc<dyn ViewHost>, ) -> Result<RequestId, ViewError>

Flutter’s AddView, for the app: asks for a view that draws into layer, which the app made with the platform’s compositor, opaque or not, and places itself, at metrics, asking what it asks of the system of host. The view arrives as a window’s does, through EmbedderClient::view_added, carrying the id answered here (View::request_id); it is in sight until the app says otherwise (set_view_in_sight), and its frames follow the screen its metrics name. Refused at once, with ViewError::Unsupported, where the host cannot draw a view into layer.

fn set_view_metrics(&self, view: ViewId, metrics: ViewMetrics)

Flutter’s SendWindowMetricsEvent, for a view the app added with add_view, which the framework hears of through EmbedderClient::view_metrics_changed; refused for any other view, whose holder gives it its metrics.

fn set_view_in_sight(&self, view: ViewId, in_sight: bool)

Whether a view the app added is in sight, as only the app knows where it placed the view’s layer: its frames are held while it is not, as a window’s are while the window is minimized or occluded. Refused for any other view, as its metrics are.

fn remove_view(&self, view: ViewId)

Flutter’s RemoveView, for a view the app added, refused for any other as its metrics are: the view lets go of its layer, and the framework hears of it through EmbedderClient::view_removed.

fn send_pointer_reports(&self, reports: Vec<PointerReport>)

Flutter’s SendPointerEvent, for the app: what pointing devices did over any view, a window’s included, which the framework hears as it hears the host’s own reports (EmbedderClient::pointer_reports), through the one converter that numbers every pointer. Each device of a forwarded stream (its mouse, trackpad and pen, and each touch from landing to lifting) takes a device number no other stream uses, a random 64-bit one for now, since the converter keeps one state per device number, a forwarding app’s own host numbers its devices as this one does, 0, 1, 2 upward, and two streams with no order between them would mix their devices’ states in one (native-surfaces decision 36).

fn send_view_focus_event(&self, event: ViewFocusEvent)

Flutter’s SendViewFocusEvent, for the app: a view’s focus change, which the framework hears as it hears the host’s own (EmbedderClient::view_focus_changed), so that the keys the host reports go where the framework’s focus is.

Dyn Compatibility

This trait is dyn compatible.

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

Implementors