CallKit + WebRTC: CallKit call is getting disconnected when pressing lock / Power button in iOS

Question

It is a conferencing app and I am initiating outgoing call to make my VoIP call as high priority and doesn't interrupt the incoming call when i am in VoIP call.

I am using WebRTC + CallKit in my App. I started a call and when I press Lock / Power button then the CallKit call is getting disconnected and the My Voip call audio route changes to Receiver and remains.

Why locking the iPhone terminating the call.

Here is my Code.

 var callUUID: UUID?

extension AppDelegate {
    func initiateCallKitCall() {
        let config = CXProviderConfiguration(localizedName: "AppName")
        config.includesCallsInRecents = false;
        config.supportsVideo = true;
        config.maximumCallsPerCallGroup = 1
        provider = CXProvider(configuration: config)
        guard let provider = provider else { return }
        provider.setDelegate(self, queue: nil)
        callController = CXCallController()
        guard let callController = callController else { return }
        callUUID = UUID()
        let transaction = CXTransaction(action: CXStartCallAction(call: callUUID!, handle: CXHandle(type: .generic, value: "AppName")))
        callController.request(transaction, completion: { error in
            print("Error is : \(String(describing: error))")
        })

    }

    func endCallKitCall(userEnded: Bool) {
        self.userEnded = userEnded
        guard provider != nil else { return }
        guard let callController = callController else { return }
        if let uuid = callUUID {
            let endCallAction = CXEndCallAction(call: uuid)
            callController.request(
                CXTransaction(action: endCallAction),
                completion: { error in
                    if let error = error {
                        print("Error: \(error)")
                    } else {
                        print("Success")
                    }
                })
        }
    }

    func isCallGoing() -> Bool {
        let callController = CXCallController()
        if callController.callObserver.calls.count != 0 {
            return true
        }
        return false
    }
}

extension AppDelegate: CXProviderDelegate {

    func providerDidReset(_ provider: CXProvider) {
        print("-Provider-providerDidReset")
    }

    func provider(_ provider: CXProvider, perform action: CXAnswerCallAction) {
        print("-Provider-perform action: CXAnswerCallAction")
        action.fulfill()
    }

    func provider(_ provider: CXProvider, perform action: CXEndCallAction) {
        action.fulfill()
        print("-Provider: End Call")
    }

    func provider(_ provider: CXProvider, perform action: CXStartCallAction) {
        action.fulfill()

        DispatchQueue.main.asyncAfter(wallDeadline: DispatchWallTime.now() + 3) {
            provider.reportOutgoingCall(with: action.callUUID, startedConnectingAt: Date())
            DispatchQueue.main.asyncAfter(wallDeadline: DispatchWallTime.now() + 1.5) {
                provider.reportOutgoingCall(with: action.callUUID, connectedAt: Date())
            }
        }
    }

    func provider(_ provider: CXProvider, perform action: CXSetHeldCallAction) {
        action.fulfill()
    }

    func provider(_ provider: CXProvider, didActivate audioSession: AVAudioSession) {
        RTCAudioSession.sharedInstance().audioSessionDidActivate(audioSession)
        RTCAudioSession.sharedInstance().isAudioEnabled = true
    }

    func provider(_ provider: CXProvider, didDeactivate audioSession: AVAudioSession) {
        RTCAudioSession.sharedInstance().audioSessionDidDeactivate(audioSession)
        RTCAudioSession.sharedInstance().isAudioEnabled = false
    }
}

Answer 1

The power button ends a call if and only if the call is running through the built-in speaker on top of the screen (receiver). In any other case (i.e. the audio is playing through headphones, Bluetooth or built-in loudspeaker) the power button will not end the call.

The same is true with the native phone calls.