Struct ViewTreeWatcherProxy

pub struct ViewTreeWatcherProxy { /* private fields */ }

Implementations

impl ViewTreeWatcherProxy

pub fn new(channel: AsyncChannel) -> Self

Create a new Proxy for fuchsia.ui.observation.geometry/ViewTreeWatcher.

pub fn take_event_stream(&self) -> ViewTreeWatcherEventStream

Get a Stream of events from the remote end of the protocol.

Panics

Panics if the event stream was already taken.

pub fn watch( &self, ) -> QueryResponseFut<WatchResponse, DefaultFuchsiaResourceDialect>

A method of obtaining view tree snapshots for a particular view.

This call is formulated as a “hanging get” pattern: the client asks for a set of recent snapshots, and receives them via the callback. This pull-based approach ensures that clients consume events at their own pace; events don’t clog up the channel in an unbounded manner.

Error Handling. If Error is unset, the client may assume that the the response contains updates with complete information over its epoch.

Flow control. The caller is allowed at most one in-flight |Watch| call at a time; it is a logical error to have concurrent calls to |Watch|. Non-compliance results in channel closure.

Client pacing. The server will dispatch snapshots to the caller on a lossless, best-effort basis, but the caller must allocate enough time to keep up with new snapshots.

Trait Implementations

impl Clone for ViewTreeWatcherProxy

fn clone(&self) -> ViewTreeWatcherProxy

Returns a copy of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Debug for ViewTreeWatcherProxy

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

Formats the value using the given formatter.

impl Proxy for ViewTreeWatcherProxy

type Protocol = ViewTreeWatcherMarker

The protocol which this Proxy controls.

fn from_channel(inner: AsyncChannel) -> Self

Create a proxy over the given channel.

fn into_channel(self) -> Result<AsyncChannel, Self>

Attempt to convert the proxy back into a channel.

fn as_channel(&self) -> &AsyncChannel

Get a reference to the proxy’s underlying channel.

fn into_client_end(self) -> Result<ClientEnd<Self::Protocol>, Self>

Attempt to convert the proxy back into a client end.

fn is_closed(&self) -> bool

Returns true if the proxy has received the PEER_CLOSED signal.

fn on_closed(&self) -> OnSignals<'_, Unowned<'_, Handle>>

Returns a future that completes when the proxy receives the PEER_CLOSED signal.

impl ViewTreeWatcherProxyInterface for ViewTreeWatcherProxy

type WatchResponseFut = QueryResponseFut<WatchResponse>

fn watch(&self) -> Self::WatchResponseFut