Switch Live Stream - Flutter

Overview

switchTo() moves the participant to another live stream without leave() and a new join.

switchTo()

Parameters

• roomId (String, required): ID of the new liveStream to join
• token (String, optional, named): VideoSDK token for the new liveStream. Without it, the SDK uses the token you joined with.

switchTo() returns a Future that throws a VideoSDKError when the SDK refuses the switch, for example 3073 (ERROR_INVALID_PARAMETER) for an empty id. When the move to the new liveStream completes:

• Events.roomLeft fires with LeaveReason.SWITCH_ROOM for the liveStream you left.
• Events.roomJoined fires again, with a Map whose switchRoomId is the id of the liveStream you switched to.

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

class LiveStreamView extends StatefulWidget {
  final Room livestream;
  final String token;

  const LiveStreamView({
    Key? key,
    required this.livestream,
    required this.token,
  }) : super(key: key);

  @override
  State<LiveStreamView> createState() => _LiveStreamViewState();
}

class _LiveStreamViewState extends State<LiveStreamView> {
  late Room _room;

  @override
  void initState() {
    super.initState();
    _room = widget.livestream;
    registerEvents();
  }

  void registerEvents() {
    _room.on(Events.roomLeft, _onRoomLeft);
    _room.on(Events.roomJoined, _onRoomJoined);
  }

  void _onRoomLeft(LeaveReason? reason) {
    // A switch also fires roomLeft, so keep the liveStream screen open.
    if (reason == LeaveReason.SWITCH_ROOM) return;
    // Close the liveStream screen here for any other reason.
  }

  void _onRoomJoined(Map<String, dynamic>? switchInfo) {
    if (switchInfo != null) {
      print("Switched to liveStream ${switchInfo['switchRoomId']}");
    }
  }

  Future<void> _handleSwitchRoom() async {
    try {
      // token is optional
      await _room.switchTo("<Desired - livestream-id>", token: widget.token);
    } on VideoSDKError catch (e) {
      print("Switch failed: ${e.code} ${e.name}");
    }
  }

  @override
  void dispose() {
    _room.off(Events.roomLeft, _onRoomLeft);
    _room.off(Events.roomJoined, _onRoomJoined);
    super.dispose();
  }

  @override
  Widget build(BuildContext context) {
    return ElevatedButton(
      child: const Text('Switch livestream'),
      onPressed: () => _handleSwitchRoom(),
    );
  }
}

Important Considerations

Room Status

• The destination liveStream must be active before attempting to switch.
• If the destination liveStream is inactive or doesn't exist, the switch will fail.

Leave Handling

• Events.roomLeft also fires when you switch, with LeaveReason.SWITCH_ROOM. If your roomLeft handler closes the liveStream screen, skip it for this reason, as the example does. The room stays usable after a switch.

Token Management

• Token Expiry: Be careful with short-lived tokens when using the switch feature.
  • If you're using short-lived tokens for security reasons, always provide a new token in the switchTo method.
  • Tokens that expire during a liveStream can cause unexpected disconnections.
• Best Practice: For frequent switches, use tokens with reasonable expiry times or implement a token refresh mechanism.

API Reference

• switchTo
• Events.roomJoined
• Events.roomLeft