Struct Runtime 

pub struct Runtime { /* private fields */ }

The execution engine for a vtui application.

A Runtime owns all state required to execute a component tree, including registered draw handlers, event listeners, and internal queues. It is built from a fully-declared Component and is responsible for driving the draw–update lifecycle.

Event loop model

The runtime operates in a strict, single-threaded loop with well-defined phases:

Draws occur first in order to calculate layout for potential hit-testing events such as mouse clicks. These occur synchronously from parent to children components.

A runtime update is performed immediately after, which blocks the event loop until it can consume some event. This can range from user IO, promise completions/cancellations, tick events, and more. It is also possible for the runtime to perform batching or coalescing of events in a manner that is invariant to the draw function.

During a runtime update, a listener may potentially politely request shutdown. Once the runtime is comfortable with a shutdown, the event loop exits.

Concurrency

The runtime is single-threaded and not Send or Sync. Concurrent systems, such as async tasks or input streams, may enqueue events via channels, but the runtime itself processes all events deterministically on one thread.

Implementations

impl Runtime

pub fn new(draw: Option<Box<dyn FnMut(DrawContext<'_>)>>) -> Self

pub fn update(&mut self)

pub fn draw(&mut self, frame: &mut Frame<'_>)

pub fn should_exit(&self) -> bool

Trait Implementations

impl Default for Runtime

fn default() -> Runtime

Returns the “default value” for a type.