How to fix Call to main actor-isolated initializer 'init(frame:)' in a synchronous nonisolated context in Apple AVCam app? porting to swift 6

Using Swift
1

I am testing some swift 6 migrations in xcode 16.1 beta and I am trying to migrate the Apple CamAV app that was created in wwdc24 to swift 6 but I don't know how to fix this error in the init.

Errors:

Call to main actor-isolated initializer 'init(frame:)' in a synchronous nonisolated context; this is an error in the Swift 6 language mode

For all imageView properties.
Main actor-isolated property 'contentMode' can not be mutated from a nonisolated context; this is an error in the Swift 6 language mode

class PreviewView: UIView, PreviewTarget {

    init() {
        super.init(frame: .zero)
#if targetEnvironment(simulator)
        // The capture APIs require running on a real device. If running
        // in Simulator, display a static image to represent the video feed.
        let imageView = UIImageView(frame: UIScreen.main.bounds)
        imageView.image = UIImage(named: "video_mode")
        imageView.contentMode = .scaleAspectFill
        imageView.autoresizingMask = [.flexibleWidth, .flexibleHeight]
        addSubview(imageView)
#endif
    }
    
    required init?(coder: NSCoder) {
        fatalError("init(coder:) has not been implemented")
    }
    
    // Use the preview layer as the view's backing layer.
    override class var layerClass: AnyClass {
        AVCaptureVideoPreviewLayer.self
    }
    
    var previewLayer: AVCaptureVideoPreviewLayer {
        layer as! AVCaptureVideoPreviewLayer
    }
    
    nonisolated func setSession(_ session: AVCaptureSession) {
        // Connects the session with the preview layer, which allows the layer
        // to provide a live view of the captured content.
        Task { @MainActor in
            previewLayer.session = session
        }
    }
}
2 Likes