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. CallSettingsBuilder class takes the 2 mandatory parameters as a part of the constructor:
  1. UIView i.e a view in which you want to show the callingView inside it.
  2. An object of the RelativeLayout. The calling UI will be loaded in this relative layout provided.
The other 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 = "12345" //you can set anything
let callView = // a UIView you want to show the calling view in

let callSettings = CallSettings.CallSettingsBuilder(callView: callView, sessionId:sessionID).setAudioOnlyCall(audioOnly: true).enableDefaultLayout(defaultLayout: true).build()

  CometChat.startCall(callSettings: callSettings, userJoined: { (user) in

     print("userJoined \(user)")
  }, userLeft: { (user) in

     print("userLeft \(user)")
  }, userListUpdated: { (userList) in
     
       print("userList \(userList)")
  }, audioModesUpdated: { (audioList) in
     
       print("audioList \(audioList)")             
  }, onError: { (error) in

      print("OnError \(error!.errorDescription)")
  }) { (call) in

      print("onCallended \(call)")
  }
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 will is false, so if not set, the call will be an audio-video call.
ParameterDescription
viewThe view that you want to show the calling view in.
sessionIDThe unique session ID available in the Call object
The OngoingCallListener listener provides you with the below callback methods:
Callback MethodDescription
userJoinedThis method is called when any other user joins the call. The user details can be obtained from the User object provided.
userLeftThis method is called when a user leaves the call. The details of the user can be obtained from the provided User object.
onErrorThis method is called when there is some error in establishing the call.
callEndedThis method is called when the call is successfully ended. The call details can be obtained from the Call object provided.
userListUpdatedThis method is called when there is some error in establishing the call.
audioModesUpdatedThis method is called when the call is successfully ended. The call details can be obtained from the Call object provided.

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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. UIView i.e a view in which you want to show the callingView inside it.
  2. An object of the RelativeLayout. The calling UI will be loaded in this relative layout provided.
The options available for customization of calls are:
SettingDescription
enableDefaultLayout(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
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
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(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(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(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
setMode(mode: CometChat.CallMode)Currently, you can set 3 modes in CallDisplayModeEnum. MODE_DEFAULT MODE_SINGLE MODE_SPOTLIGHT when MODE_DEFAULT is set our default screen will be displayed when MODE_SINGLE is set the user will be able to see the opponents video only when MODE_SPOTLIGHT is set the user will be able to see members joined count along with their name and can also pin/unpin users
setAudioOnlyCall(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
startWithAudioMuted(audioMuted: boolean)This ensures the call is started with the audio muted if set to true
startWithVideoMuted(videoMuted: boolean)This ensures the call is started with the video paused if set to true
setDefaultAudioMode(mode: CometChat.AudioMode)This method can be used if you wish to start the call with a specific audio mode. The available options are 1. SPEAKER 2. EARPIECE 3. BLUETOOTH 4. 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 own custom buttons and not use the default layout provided by CometChat, 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 switchCamera() Method to toggle between camera sources. 
let callmanager = CallManager()
callmanager.switchCamera()

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Mute Audio

You can call muteAudio() Method to mute your Audio Stream to the end-user. 
let callmanager = CallManager()
callmanager.muteAudio(mute: true) //toggle this value for unmuting the user's audio
If set to true the Audio Stream is muted and if set tofalse Audio Stream is transmitted.

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Pause Video

You can call pauseVideo() Method to pause Video Stream to the end-user. 
let callmanager = CallManager()
callmanager.pauseVideo(pauseVideo: true) //toggle this value for resuming the user's video
If set to true the Video Stream is muted and if set tofalse Video Stream is transmitted.

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Set Audio Mode

You can call setAudioMode() to set the output of the audio stream. 
let callmanager = CallManager()
callmanager.audioMode(setAudioMode: .EARPIECE)
The audio mode can have either one of the below 4 values:
  • SPEAKER
  • EARPIECE
  • BLUETOOTH
  • HEADPHONES

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End Call

You can use the CometChat.endCall() method of the CometChat class to end the call. 
var sessionID = "" // sessionId of the call

CometChat.endCall(sessionID: sessionID, onSuccess: { (call) in
            
    print("Call Ended Successfully")
}) { (error) in

    print("Error in ending the call \(error?.errorDescription)")
}

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Get 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. 
CometChat.getAudioModes { (modes) in
	print("Available audio modes received \(modes)")
}
The AudioMode class has the below properties:
  1. mode - The mode can be either one of the below values:
  • SPEAKER
  • EARPIECE
  • BLUETOOTH
  • HEADPHONES
  1. isSelected - This is a boolean value that indicates if the audio mode is the active mode.
Please noteThe CometChat.getActiveCall() method in case of Direct Calling will return nil 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 of the call and returns the number of participants that are active in the call. 
let sessionID = "12345"

 CometChat.getCallParticipantCount(sessionId: "", type: .DIRECT, onSucces:  {
      (count) in
      print("Count \(count)")
 }, onError: { (error) in
      print("OnError \(error?.errorDescription)")
 })