Change Video Input Device - Flutter

During the room at any point a participant wishes to switch his/her input video device, it can be done using the below mentioned methods.

getCameras()

• This method of the VideoSDK class will give you the list of all the available cameras which can be shown in a list.

• This method will return a list of CameraDeviceInfo which will contain the deviceId, label and kind of the camera input devices. On Android, labels look like Camera 1 (Front Camera). On iOS, the label is the camera's name, such as Front Camera, and deviceId is the same string.

changeCam()

• After selecting the desired device, you can switch the camera input by passing its deviceId to changeCam(deviceId: ...).

• Call changeCam() without a device to switch to the next camera, for example from the front camera to the back camera.

• To switch to a custom camera track instead, pass it as changeCam(customCameraTrack: track). This also turns the camera on.

• changeCam() returns a Future that throws a VideoSDKError if the switch fails, for example 3051 when the camera is not available. The same error also reaches your Events.error handler.

• VideoSDK.getSelectedVideoDevice() returns the camera in use: the one the room opened when you joined, or the one you switched to.

• To choose the camera the room starts with, pass defaultCamera to VideoSDK.createRoom(): FacingMode.FRONT, the default, or FacingMode.BACK.

Future<void> switchToNextCamera() async {
  try {
    // No device: switch to the next camera
    await _room.changeCam();
  } on VideoSDKError catch (error) {
    print("changeCam failed: ${error.code} ${error.name}");
  }
}

Example

import 'package:flutter/material.dart';
import 'package:videosdk/videosdk.dart';

class RoomScreen extends StatefulWidget {
  const RoomScreen({Key? key}) : super(key: key);

  @override
  _RoomScreenState createState() => _RoomScreenState();
}

class _RoomScreenState extends State<RoomScreen> {
  late Room _room;
  List<CameraDeviceInfo>? cameras = [];

  @override
  void initState() {
    super.initState(); 
    fetchCameras();
  }

  void fetchCameras() async {
    cameras = await VideoSDK.getCameras();
    setState(() {});  
  }

  Future<void> changeCam(CameraDeviceInfo device) async {
    try {
      await _room.changeCam(deviceId: device.deviceId);
    } on VideoSDKError catch (error) {
      print("changeCam failed: ${error.code} ${error.name}");
    }
  }

  @override
  Widget build(BuildContext context) {
    return Column(
      children: [
        ElevatedButton(
          child: const Text("Change Camera"),
          onPressed: () {
            showDialog(
              context: context,
              builder: (context) => AlertDialog(
                title: const Text("Select Camera Device"),
                content: Column(
                  mainAxisAlignment: MainAxisAlignment.center,
                  mainAxisSize: MainAxisSize.min,
                  children: <Widget>[
                    SingleChildScrollView(
                      reverse: true,
                      child: cameras != null && cameras!.isNotEmpty
                          ? Column(
                              children: cameras!.map(
                                (device) => ElevatedButton(
                                  child: Text(device.label),
                                  onPressed: () async {
                                    Navigator.pop(context);
                                    await changeCam(device);
                                  },
                                ),
                              ).toList(),
                            )
                          : const Text("No Camera Devices found."),
                    ),
                  ],
                ),
              ),
            );
          },
        ),
      ],
    );
  }
}

API Reference

The API references for all the methods and events utilised in this guide are provided below.

• getCameras()
• changeCam()
• getSelectedVideoDevice()
• createRoom()