Trait AVCaptureMetadataOutputObjectsDelegate 

pub unsafe trait AVCaptureMetadataOutputObjectsDelegate: NSObjectProtocol {
    // Provided method
    unsafe fn captureOutput_didOutputMetadataObjects_fromConnection(
        &self,
        output: &AVCaptureMetadataOutput,
        metadata_objects: &NSArray<AVMetadataObject>,
        connection: &AVCaptureConnection,
    )
       where Self: Sized + Message { ... }
}

Available on crate feature AVCaptureMetadataOutput only.

Defines an interface for delegates of AVCaptureMetadataOutput to receive emitted objects.

See also Apple’s documentation

Provided Methods

unsafe fn captureOutput_didOutputMetadataObjects_fromConnection( &self, output: &AVCaptureMetadataOutput, metadata_objects: &NSArray<AVMetadataObject>, connection: &AVCaptureConnection, )

where Self: Sized + Message,

Available on crate features AVCaptureOutputBase and AVCaptureSession and AVMetadataObject only.

Called whenever an AVCaptureMetadataOutput instance emits new objects through a connection.

Parameter output: The AVCaptureMetadataOutput instance that emitted the objects.

Parameter metadataObjects: An array of AVMetadataObject subclasses (see AVMetadataObject.h).

Parameter connection: The AVCaptureConnection through which the objects were emitted.

Delegates receive this message whenever the output captures and emits new objects, as specified by its metadataObjectTypes property. Delegates can use the provided objects in conjunction with other APIs for further processing. This method will be called on the dispatch queue specified by the output’s metadataObjectsCallbackQueue property. This method may be called frequently, so it must be efficient to prevent capture performance problems, including dropped metadata objects.

Clients that need to reference metadata objects outside of the scope of this method must retain them and then release them when they are finished with them.

Trait Implementations

impl ProtocolType for dyn AVCaptureMetadataOutputObjectsDelegate

const NAME: &'static str = "AVCaptureMetadataOutputObjectsDelegate"

The name of the Objective-C protocol that this type represents.

fn protocol() -> Option<&'static AnyProtocol>

Get a reference to the Objective-C protocol object that this type represents.

impl<T> ImplementedBy<T> for dyn AVCaptureMetadataOutputObjectsDelegate

where T: ?Sized + Message + AVCaptureMetadataOutputObjectsDelegate,

Implementations on Foreign Types

impl<T> AVCaptureMetadataOutputObjectsDelegate for ProtocolObject<T>

where T: ?Sized + AVCaptureMetadataOutputObjectsDelegate,

Implementors