Trait Camera 

pub trait Camera: Send + Sync {
    // Required methods
    fn start(&self) -> Result<String, CameraError>;
    fn latest_frame(&self) -> Option<CameraFrame>;
    fn stop(&self);

    // Provided methods
    fn capture_still(&self) -> Option<CameraStill> { ... }
    fn set_torch(&self, _on: bool) -> bool { ... }
    fn lenses(&self) -> Vec<CameraLens> { ... }
    fn lens(&self) -> Option<String> { ... }
    fn use_lens(&self, _id: &str) -> bool { ... }
    fn has_flash(&self) -> bool { ... }
    fn set_flash(&self, _mode: FlashMode) -> bool { ... }
}

A running (or startable) live camera. Implementations are Send + Sync so a background preview pump can start/stop and poll frames off the UI thread.

Required Methods

fn start(&self) -> Result<String, CameraError>

Start the capture session, returning a human-readable device name. Safe to call again while already running (idempotent).

fn latest_frame(&self) -> Option<CameraFrame>

The most recent frame, or None if none has arrived yet.

fn stop(&self)

Stop the session and release the device.

Provided Methods

fn capture_still(&self) -> Option<CameraStill>

Capture a full-resolution still through the platform photo pipeline.

Blocks up to a few seconds while the device exposes and encodes. Returns None where the backend has no dedicated photo path (callers should fall back to latest_frame) or when the capture fails.

fn set_torch(&self, _on: bool) -> bool

Toggle the capture device’s torch (flashlight) while the session runs. Scanner-style apps light dim scenes instead of trying to analyze photon-starved frames. Returns false where the device has no torch or the backend has none wired; the torch dies with the session.

fn lenses(&self) -> Vec<CameraLens>

The capture devices the app may pick between, back cameras first and in field-of-view order (widest first). An empty list means the app shows no lens control: either the platform has one camera or the backend does not list them.

fn lens(&self) -> Option<String>

The id of the device the session uses, or None when nothing is open and the backend has no stored choice.

fn use_lens(&self, _id: &str) -> bool

Open id instead of the current device, keeping the session running. Returns false when the id is unknown or the backend cannot switch.

fn has_flash(&self) -> bool

Whether the current device has a flash for stills.

fn set_flash(&self, _mode: FlashMode) -> bool

What the flash does on the next capture_still. Returns false where the device has no flash or the backend has none wired; the mode dies with the session.

Dyn Compatibility

This trait is dyn compatible.

In older versions of Rust, dyn compatibility was called "object safety".

Implementors