How to using realtime camera streaming in swiftui? - streaming

Question

I build a StreamingView like this:
struct StreamingView: UIViewRepresentable {
func updateUIView(_ uiView: UIView, context: UIViewRepresentableContext<StreamingView>) {
//
}
func makeUIView(context: UIViewRepresentableContext<StreamingView>) -> UIView {
let view = UIView()
let captureSession = AVCaptureSession()
captureSession.sessionPreset = .photo
guard let captureDevice = AVCaptureDevice.default(for: .video) else { return view}
guard let input = try? AVCaptureDeviceInput(device: captureDevice) else { return view}
captureSession.addInput(input)
captureSession.startRunning()
let previewLayer = AVCaptureVideoPreviewLayer(session: captureSession)
view.layer.addSublayer(previewLayer)
previewLayer.frame = view.frame
return view
}
}
but It didn't work. how could I build a pure swiftui view for streaming?

Answer 1

Try the below demo code
Note: make sure all preparations done, like turned on Camera in capabilities, added NSCameraUsageDescription in Info.plist... and camera can be tested only on a real device.
import SwiftUI
import UIKit
import AVFoundation
class PreviewView: UIView {
private var captureSession: AVCaptureSession?
init() {
super.init(frame: .zero)
var allowedAccess = false
let blocker = DispatchGroup()
blocker.enter()
AVCaptureDevice.requestAccess(for: .video) { flag in
allowedAccess = flag
blocker.leave()
}
blocker.wait()
if !allowedAccess {
print("!!! NO ACCESS TO CAMERA")
return
}
// setup session
let session = AVCaptureSession()
session.beginConfiguration()
let videoDevice = AVCaptureDevice.default(.builtInWideAngleCamera,
for: .video, position: .unspecified) //alternate AVCaptureDevice.default(for: .video)
guard videoDevice != nil, let videoDeviceInput = try? AVCaptureDeviceInput(device: videoDevice!), session.canAddInput(videoDeviceInput) else {
print("!!! NO CAMERA DETECTED")
return
}
session.addInput(videoDeviceInput)
session.commitConfiguration()
self.captureSession = session
}
override class var layerClass: AnyClass {
AVCaptureVideoPreviewLayer.self
}
required init?(coder: NSCoder) {
fatalError("init(coder:) has not been implemented")
}
var videoPreviewLayer: AVCaptureVideoPreviewLayer {
return layer as! AVCaptureVideoPreviewLayer
}
override func didMoveToSuperview() {
super.didMoveToSuperview()
if nil != self.superview {
self.videoPreviewLayer.session = self.captureSession
self.videoPreviewLayer.videoGravity = .resizeAspect
self.captureSession?.startRunning()
} else {
self.captureSession?.stopRunning()
}
}
}
struct PreviewHolder: UIViewRepresentable {
func makeUIView(context: UIViewRepresentableContext<PreviewHolder>) -> PreviewView {
PreviewView()
}
func updateUIView(_ uiView: PreviewView, context: UIViewRepresentableContext<PreviewHolder>) {
}
typealias UIViewType = PreviewView
}
struct DemoVideoStreaming: View {
var body: some View {
VStack {
PreviewHolder()
}.frame(minWidth: 0, maxWidth: .infinity, minHeight: 0, maxHeight: .infinity, alignment: .center)
}
}