This section will guide you to start the call/conference directly with the session id of your choice. The session id is the most important parameter as all the users joining the same session id will be connected to the same call/conference.

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Implementation

The most important class that will be used in the implementation is the CallSettings class. This class allows you to set the various parameters for the call/conference. In order to set the various parameters of the CallSettings class, you need to use the CallSettingsBuilder class. Below are the various options available with the CallSettings class. The mandatory parameter is the sessionId for the call/conference. You can use the setSessionId() method of the CallSettingsBuilder to set the session Id of the call. A basic example of how to start a direct call: 
let sessionID = "SESSION_ID";
let audioOnly = false;
let deafaultLayout = true;
let callListener = new CometChat.OngoingCallListener({
    onUserListUpdated: userList => {
			console.log("user list:", userList);
    },
    onCallEnded: call => {
      console.log("Call ended:", call);
    },
    onError: error => {
        console.log('Call Error: ', error);
    },
		onAudioModesUpdated: (audioModes) => {
        console.log("audio modes:", audioModes);
    }
});

let callSettings = new CometChat.CallSettingsBuilder()
                    .enableDefaultLayout(deafaultLayout)
                    .setSessionID(sessionID)
                    .setIsAudioOnlyCall(audioOnly)
                    .setCallEventListener(callListener)
                    .build();

render(){
   return(
      <View style={{height: '100%', width: '100%', position: 'relative'}}>
          <CometChat.CallingComponent callsettings= {callSettings} />
       </View>
   );
}
The setAudioOnlyCall() method allows you to set if the call is supposed to be an audio call or an audio-video call. If set to true, the call will be an audio-only call else when set to false the call will be an audio-video call. The default is false, so if not set, the call will be an audio-video call.

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Settings

The CallSettings class is the most important class when it comes to the implementation of the Calling feature. This is the class that allows you to customize the overall calling experience. The properties for the call/conference can be set using the CallSettingsBuilder class. This will eventually give you and object of the CallSettings class which you can pass to the startCall() method to start the call. The mandatory parameters that are required to be present for any call/conference to work are:
  1. sessionId - The unique session Id for the call/conference session.
The options available for customization of calls are:
SettingDescription
enableDefaultLayout(defaultLayout: boolean)If set to true enables the default layout for handling the call operations. If set to false it hides the button layout and just displays the Call View. Default value = true
showEndCallButton(showEndCallButton: boolean)If set to true it displays the EndCallButton in Button Layout. if set to false it hides the EndCallButton in Button Layout. Default value = true
showPauseVideoButton(showPauseVideoButton: boolean)If set to true it displays the PauseVideoButton in Button Layout. if set to false it hides the PauseVideoButton in Button Layout. Default value = true
showMuteAudioButton(showMuteAudioButton: boolean)If set to true it displays the MuteAudioButton in Button Layout. if set to false it hides the MuteAudioButton in Button Layout. Default value = true
showSwitchCameraButton(showSwitchCameraButton: boolean)If set to true it displays the SwitchCameraButton in Button Layout. if set to false it hides the SwitchCameraButton in Button Layout. Default value = true
showAudioModeButton(showAudioModeButton: boolean)If set to true it displays the AudioModeButton in Button Layout. if set to false it hides the AudioModeButton in Button Layout. Default value = true
setIsAudioOnlyCall(audioOnly: boolean)If set to true, the call will be strictly an audio call. If ser to false, the call will be an audio-video call. Default value = false
setMode(mode: string)CometChat provides 3 options for the calling UI. 1. CometChat.CALL_MODE.DEFAULT 2. CometChat.CALL_MODE.SPOTLIGHT 3. CometChat.CALL_MODE.SINGLE Default value = CometChat.CALL_MODE.DEFAULT
startWithAudioMuted(audioMuted: boolean)This ensures the call is started with the audio muted if set to true. Default value = false
startWithVideoMuted(videoMuted: boolean)This ensures the call is started with the video paused if set to true. Default value = false
setDefaultAudioMode(audioMode: string)This method can be used if you wish to start the call with a specific audio mode. The available options are 1. CometChat.AUDIO_MODE.SPEAKER = “SPEAKER” 2. CometChat.AUDIO_MODE.EARPIECE = “EARPIECE” 3. CometChat.AUDIO_MODE.BLUETOOTH = “BLUETOOTH” 4. CometChat.AUDIO_MODE.HEADPHONES = “HEADPHONES”
In case you wish to achieve a completely customized UI for the Calling experience, you can do so by embedding default android buttons to the screen as per your requirement and then use the below methods to achieve different functionalities for the embedded buttons. For the use case where you wish to align your custom buttons and not use the default layout provided by the SDK you can embed the buttons in your layout and use the below methods to perform the corresponding operations:

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Switch Camera

You can call the switchCamera() Method to toggle between camera sources. 
let callController = CometChat.CallController.getInstance();
callController.switchCamera();

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Mute Audio

You can call muteAudio(mute: boolean) Method to mute your Audio Stream to the end-user. 
let callController = CometChat.CallController.getInstance();
callController.muteAudio(true);
if set to true the Audio Stream is muted and if set to false Audio Stream is transmitted.

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Pause Video

You can call pauseVideo(pause: boolean) Method to pause Video Stream to the end-user. 
let callController = CometChat.CallController.getInstance();
callController.pauseVideo(true);
if set to true the Video Stream is muted and if set to false Video Stream is transmitted.

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Set Audio Mode

You can call the setAudioMode(mode: string) to set the output of the audio stream. 
let callController = CometChat.CallController.getInstance();
let earPieceMode = CometChat.AUDIO_MODE.EARPIECE;
callController.setAudioMode(earPieceMode);
The audio mode string can have either one of the below 4 values:
  • CometChat.AUDIO_MODE.SPEAKER = “SPEAKER”
  • CometChat.AUDIO_MODE.EARPIECE = “EARPIECE”
  • CometChat.AUDIO_MODE.BLUETOOTH = “BLUETOOTH”
  • CometChat.AUDIO_MODE.HEADPHONES= “HEADPHONES”

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End Call

You can use the CometChat.endCall() method of the CometChat class to end the call. 
CometChat.endCall("SESSION_ID_FOR_THE_CALL").then(
	call => {
		console.log('call ended', call);
	}, error => {
		console.log('error', error);
	}
);

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Get the list of available audio modes

This method will return the list of available audio modes. Based on the list received, you can set the audio mode for the ongoing call using the setAudioMode() method. 
let callController = CometChat.CallController.getInstance();
callController.getAudioOutputModes().then(
    modes => {
      console.log('getAudioOutputModes :: modes', modes);
    }, error => {
      console.log('getAudioOutputModes :: error', error);
    }
);
The AudioMode class has the below properties:
  1. mode - The mode can be either one of the below values:
  • CometChat.AUDIO_MODE.SPEAKER = “SPEAKER”
  • CometChat.AUDIO_MODE.EARPIECE = “EARPIECE”
  • CometChat.AUDIO_MODE.BLUETOOTH = “BLUETOOTH”
  • CometChat.AUDIO_MODE.HEADPHONES= “HEADPHONES”
  1. isSelected - This is a boolean value that indicates if the audio mode is the active mode.
The CometChat.getActiveCall() method in case of Direct Calling will return null and all the details related to the call session will have to be saved and maintained at your end.

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Call Participant Count

In order to get the number of participants in any call, you can use the getCallParticipantCount() method. This method takes the session id for the call and returns the number or participants that are active in the call. 
let sessionId = "CALL_SESSION_ID";
let callType = "DIRECT";

CometChat.getCallParticipantCount(sessionId, callType).then(
	count => {
		console.log("Participants count =", count);
	}, error => {
		console.log("Some error occurred =", error);
	}
);