Struct Host 

pub struct Host { /* private fields */ }

Implementations

impl Host

pub fn new(app: fn() -> Element) -> Self

pub fn with_theme(app: fn() -> Element, theme: Theme) -> Self

The theme the application chose. Choosing nothing follows the host platform, with Material 3 where the platform has no look of its own.

pub fn rebuild(&mut self) -> Result<&[u8], ProtocolError>

pub fn dispatch_event( &mut self, bytes: &[u8], ) -> Result<(&[u8], i64), ProtocolError>

pub fn arena(&self) -> (*const u8, usize)

The batch arena, reported to the Renderer on every boundary call.

pub fn resync(&mut self) -> Result<(&[u8], i64), ProtocolError>

Answers with the whole tree, for a Renderer that no longer has a node table.

The Host keeps no shadow of what it has already sent, so the only way to produce a full-tree batch is to build the application again, and that resets component state. A Renderer that keeps its node table across a configuration change never needs this call, which is what the Android host does.

pub fn dispatch( &mut self, event: HostEvent<'_>, ) -> Result<(&[u8], i64), ProtocolError>

pub fn render_frame( &mut self, _frame_time_nanos: u64, ) -> Result<&[u8], ProtocolError>

pub fn append_text(&mut self, node_id: u32, tail: &str)

Queues a streamed tail for the next frame. Tokens arriving inside one frame are merged into a single AppendText record, so a token never costs a batch of its own.

pub fn register_asset( &mut self, asset_id: u32, kind: AssetKind, bytes: &[u8], ) -> Result<&[u8], ProtocolError>

Registers one asset and returns the batch that carries it.

The bytes are copied once here and once more by the Renderer into its cache. After that the id is all that travels, so drawing the same image every frame costs a fixed-layout property record and nothing else.

pub fn register_icon( &mut self, asset_id: u32, role: IconRole, ) -> Result<&[u8], ProtocolError>

Registers an icon by the meaning it carries. The Renderer holds the artwork for every design system, so what crosses is the role and not a picture or a name.

pub fn release_asset(&mut self, asset_id: u32) -> Result<&[u8], ProtocolError>

Drops the asset from the Renderer’s cache. Using the id afterwards is a reported protocol error.

pub fn set_text( &mut self, node_id: u32, text: &str, selection: Option<Selection>, ) -> Result<&[u8], ProtocolError>

pub fn handler_target(&self, handler_id: u64) -> Option<ElementId>