Struct Batch 

pub struct Batch { /* private fields */ }

One batch, written by the runtime and by the Host into the same arena.

The Host opens it with Batch::begin, writes the records that are its own (the theme, the window, assets, messages, notifications, streamed tails) and has the runtime write the tree’s records between them, then closes it with Batch::finish. The bytes that come back are what the boundary hands the Renderer.

A runtime has no fallible way to report a bad record from the middle of a diff, so Batch::fail keeps the error and finish returns it in place of the batch.

Implementations

impl Batch

pub fn new() -> Self

Sized so that an ordinary screen’s batches never grow it: once warm, writing a frame allocates nothing.

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

The batch arena, so a Renderer that reads Host memory through a mapped view can be handed one.

pub fn begin(&mut self)

Starts a new batch, discarding the previous one and any error it carried.

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

Closes the batch and returns its bytes, or the first error written into it.

pub fn write(&mut self, mutation: Mutation<'_>)

Writes one record. After an error nothing more is written: the batch is already going to be refused.

pub fn fail(&mut self, error: ProtocolError)

Records an error found while building the batch. finish returns it.

pub fn set_theme(&mut self, theme: Theme)

The root theme record. Written once per rebuild, never per frame.

pub fn set_window(&mut self, window: Window)

The root window record. Written once per rebuild, never per frame.

pub fn set_text_node( &mut self, node_id: u32, text: &str, selection: Option<Selection>, )

pub fn register_asset(&mut self, asset_id: u32, kind: AssetKind, bytes: &[u8])

Copies one asset into the batch. The bytes ride behind the records, and the Renderer takes its own copy inside the call that carries them.

pub fn release_asset(&mut self, asset_id: u32)

pub fn show_message( &mut self, handler_id: u64, text: &str, action: &str, duration: MessageDuration, )

Writes one transient message into the batch.

It names no node, because a message is not in the tree: it is a sentence with a lifetime, and that lifetime belongs to the Renderer.

pub fn append_text_node(&mut self, node_id: u32, text: &str)

Appends the streamed tail to a Text node without resending its whole value.

Trait Implementations

impl Default for Batch

fn default() -> Self

Returns the “default value” for a type.