- Local peer is a device running the app right now.
- Remote peer is an opponent device.
- Signaling. At this phase, the peers’ local IPs and ports where they can be reached (ICE candidates) are exchanged as well as their media capabilities and call session control messages.
- Discovery. At this phase, the public IPs and ports at which endpoints can be reached are discovered by STUN/TURN server.
- Establishing a connection. At this phase, the data are sent directly to each party of the communication process.
In order to start using Video Calling Module, you need to connect to QuickBlox Chat first. The signaling in the QuickBox WebRTC module is implemented over the XMPP protocol using QuickBlox Chat Module. It acts as a signaling transport for Video Calling API.
Please use this WebRTC Video Calling to make the Group Calls with 4 or fewer users. Because of Mesh architecture we use for multi-point where every participant sends and receives its media to all other participants, the current solution supports group calls with up to 4 people.
Before you begin
- Register a QuickBlox account. This is a matter of a few minutes and you will be able to use this account to build your apps.
- Configure QuickBlox SDK for your app. Check out Setup page for more details.
- Create a user session to be able to use QuickBlox functionality. See Authentication page to learn how to do it.
- Connect to the Chat server to provide a signaling mechanism for Video Calling API. Follow our Chat page to learn about chat connection settings and configuration.
Initialize WebRTC
WebRTC module allows to process calls. When a call is initiated or received, a call session is created. If the module is not initialized, it will not be able to create a call session and process calls consequently. To initialize WebRTC module callinit()
method.
Dart
If you miss calling
init()
method, a Exception
is returned: The call service is not connected
.Manage calls
Each WebRTC session is assigned a unique session identifier (
sessionId
). You can get the sessionId
from the session
value returned from call()
, accept()
, reject()
, hangUp()
methods or from any event emitted by QB.webrtc
module. See a full list of callbacks here.StreamSubscription
that you should unsubscribe when you need in dispose()
method. Learn more details about the event handler configuration in the Event handler section.
Dart
The example above shows assigning one handler for all module events but you can assign separate handlers for each event.
Initiate a call
To call users, you should create a call session and start calling usingcall()
method.
Dart
Argument | Description | Description |
---|---|---|
opponentsIds | yes | A list of opponents IDs. |
sessionType | yes | Call type: QB.webrtc.RTC\_SESSION\_TYPE.VIDEO , QB.webrtc.RTC\_SESSION\_TYPE.AUDIO . |
NoteAfter this, your opponents will receive an event
QB.webrtc.EVENT_TYPE.CALL
.Accept a call
To accept a call request, callaccept()
method and pass sessionId
to tell SDK which call session to accept.
Dart
Argument | Required | Description |
---|---|---|
sessionId | yes | Call session identifier. |
userInfo | no | Custom user data. |
Reject a call
To reject a call request, usereject()
method and pass sessionId
parameter to tell SDK which call session to reject.
Dart
Argument | Required | Description |
---|---|---|
sessionId | yes | Call session identifier. |
userInfo | no | Custom user data. |
End a call
To end a call, usehangUp()
method and pass sessionId
parameter to tell SDK which call session to end.
Dart
Argument | Required | Description |
---|---|---|
sessionId | yes | Call session identifier. |
userInfo | no | Custom user data. |
Release resource
When you don’t want to receive and process video calls, for example, when a user is logged out, you have to releaseQB.webrtc
module. Call release()
method that allows to unregister QB.webrtc
module from receiving any video chat events and closes existing signaling channels.
Dart
release()
method should be called when a video track is no more valid. If you don’t call this method, you will get a memory leak.Local/remote video view
Set up two RTCVideoView for remote and local video tracks to be able to show the video.- A remote video track represents a remote peer video stream from a remote camera app. Specify initial value to RTCVideoView -
RTCVideoViewController
for the remote camera app of the remote peer. - A local video track represents a local peer video stream from a local camera app. Specify initial value to RTCVideoView is
RTCVideoViewController
for the local camera app of the local peer.
QBRTCEventTypes.RECEIVED_VIDEO_TRACK
manually. Thus, once the SDK receives data that a remote video track was received, it creates the event of RECEIVED_VIDEO_TRACK
type with userId
and sessionId
properties.
Dart
play()
and pass sessionId
and userId
parameters to it. If userId
matches with the one in properties, the video starts playing.
Dart
Argument | Required | Description |
---|---|---|
sessionId | yes | Call session identifier. |
userId | yes | The ID of the local peer. |
opponentId | yes | The ID of the remote peer. |
Event handler
To process events such as incoming call, call reject, hang up, etc. you need to set up the event handler. The event handler processes various events that happen with the call session or peer connection in your app. The events are emitted by the WebRTC module of QuickBlox Flutter SDK.Once the WebRTC module is initialized, it can start emitting events, so you can assign event handler even before module initialization.
accept()
method is called when your call has been accepted by the user. This method receives information about the call session and additional key-value data about the user.
QuickBlox Flutter SDK persistently interacts with the server via XMPP connection that works as a signaling transport for establishing a call between two or more peers. It receives the callbacks of the asynchronous events which happen with the call and peer connection. This allows you to track these events and build your own video calling features around them.
Call session events
The table below lists all supported call session event types.Event type | Description |
---|---|
QBRTCEventTypes.CALL | An incoming call event has been received by the peer after the call session has been initiated. |
QBRTCEventTypes.ACCEPT | An incoming call has been accepted by the peer. |
QBRTCEventTypes.REJECT | An incoming call has been rejected by the remote peer without accepting the call. |
QBRTCEventTypes.HANG_UP | An accepted call has been ended by the peer by pressing the hang-up button. |
QBRTCEventTypes.RECEIVED_VIDEO_TRACK | A remote video track has been received by the remote peer. |
QBRTCEventTypes.PEER_CONNECTION_STATE_CHANGED | A peer connection state has been changed. View all available peer connection states in the Peer connection states section. |
QBRTCEventTypes.NOT_ANSWER | No answer received from the remote peer within the timer expiration period. |
QBRTCEventTypes.CALL_END | An accepted call has been ended. A call session was closed. |
Dart
Argument | Required | Description |
---|---|---|
type | yes | The name of the event you have subscribed to. |
payload | yes | Available if the event transmits the data. Almost all events contain session (to identify in which session this event occurred) and userId (to indicate initiator of the event) properties. |
Peer connection state
The peer connection state can change. To monitor the states of your peer connections (users), you need to add an event handler forQB.webrtc.EVENT\_TYPE.PEER\_CONNECTION\_STATE\_CHANGED
event type.
Dart
Connection state | Description |
---|---|
QBRTCPeerConnectionStates.NEW | Gathering information to establish connection. |
QBRTCPeerConnectionStates.CONNECTED | A peer is connected to the call session. |
QBRTCPeerConnectionStates.FAILED | A peer failed to join the call session. |
QBRTCPeerConnectionStates.DISCONNECTED | A peer is disconnected from the call session. |
QBRTCPeerConnectionStates.CLOSED | A call session is closed by the peer. |
Resources
A regular call workflow.