Enum RegistryRequest

pub enum RegistryRequest {
    RegisterScopedViewTreeWatcher {
        context_view: u64,
        watcher: ServerEnd<ViewTreeWatcherMarker>,
        responder: RegistryRegisterScopedViewTreeWatcherResponder,
    },
}

*** ONLY FOR USE IN PLATFORM COMPONENTS *** This is a sensitive protocol. It provides unlimited visibility into any view tree, if handed the tree root’s view ref KOID. Hand it out ONLY to platform components, such as Accessibility Manager or UI Test Manager.

Regular UI clients uses should obtain observation protocols through a graphics factory function (see |fuchsia.ui.composition.ViewBoundProtocols|), which securely ties observation protocols to a specific view client.

Variants

RegisterScopedViewTreeWatcher

Sets up a geometry ViewTreeWatcher channel which reports the view tree geometry for a specific view, identified by context_view. The data received describes the context_view and its descendant views.

This method may be called multiple times to obtain multiple geometry ViewTreeWatchers. Typical usage is to obtain just one geometry ViewTreeWatcher.

Client can freely disconnect this Registry endpoint after this method returns and the ViewTreeWatcher endpoint will remain active.

Flow control. The caller is allowed at most one in-flight call at a time. Subsequent calls must wait until the acknowledgment returns. Non-compliance results in channel closure.

Client synchronization. The method response signifies that the server has processed the channel endpoint. A client can synchronize its next actions based on this guarantee (for example, trigger a change in view geometry without the change “getting lost”).

View lifecycle. The view represented by context_view must first be created. Otherwise, geometry channel’s server endpoint is closed.

• request context_view a view’s identity, which serves as the root of a view tree
• request geometry a channel to observe context_view’s view tree

• response acknowledgement that geometry is connected to the server

Fields

context_view: u64

watcher: ServerEnd<ViewTreeWatcherMarker>

responder: RegistryRegisterScopedViewTreeWatcherResponder

Implementations

impl RegistryRequest

pub fn into_register_scoped_view_tree_watcher( self, ) -> Option<(u64, ServerEnd<ViewTreeWatcherMarker>, RegistryRegisterScopedViewTreeWatcherResponder)>

pub fn method_name(&self) -> &'static str

Name of the method defined in FIDL

Trait Implementations

impl Debug for RegistryRequest

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.