This guide walks you through adding voice and video calling capabilities to your Android application using the CometChat UI Kit.
Make sure you’ve completed the Getting Started guide before proceeding.
enableCalling: true makes the Calls SDK dependency mandatory — otherwise the app crashes at
launch. With the flag set, CometChatUIKit.initFromSettings() calls initCometChatCalls(), which
throws if com.cometchat:calls-sdk-android is absent:
java.lang.NoClassDefFoundError: Failed resolution of: Lcom/cometchat/calls/core/CometChatCalls$SessionSettingsBuilder; at com.cometchat.uikit.core.CometChatUIKit.initCometChatCalls(CometChatUIKit.kt:229)
The crash happens in onCreate, before any UI renders — the flag name gives no hint that a
dependency is implied. Change the flag and the dependency together, or leave enableCalling as
false in an app that does not use calling.
After adding this dependency, the Android UI Kit will automatically detect it and activate the calling features.Once calling is active, the voice and video call buttons render in the MessageHeader:
Kotlin (XML Views)
Jetpack Compose
The call buttons appear automatically — CometChatMessageHeader detects that calling is enabled, so no extra code is needed.
The CometChatMessageHeader composable hides the call buttons by default (hideVoiceCallButton and hideVideoCallButton both default to true). Show them explicitly:
CometChatMessageHeader( user = user, hideVoiceCallButton = false, hideVideoCallButton = false)
Enabling calling in an app that already has logged-in users requires a re-login.CometChatUIKit.login() short-circuits when the same uid already has a persisted session — it returns onSuccess without logging the Calls SDK in, so the Calls SDK has no auth token and CometChatCallLogs shows a silent error state (logcat: User auth token cannot be null). After calling is first enabled, log out and log in again (CometChatUIKit.logout(...) then CometChatUIKit.login(...)), and wire onError on CometChatCallLogs during development so this failure is visible.
To receive incoming calls globally in your app, add a CallListener before initializing the CometChat UI Kit. We recommend creating a custom Application class:
Kotlin (XML Views)
Jetpack Compose
class BaseApplication : Application() { companion object { private val LISTENER_ID = "${BaseApplication::class.java.simpleName}${System.currentTimeMillis()}" } override fun onCreate() { super.onCreate() CometChat.addCallListener(LISTENER_ID, object : CometChat.CallListener { override fun onIncomingCallReceived(call: Call) { // Get the current activity context val currentActivity = getCurrentActivity() // Implement this method currentActivity?.let { val incomingCallView = CometChatIncomingCall(it) incomingCallView.call = call incomingCallView.fitsSystemWindows = true incomingCallView.onError = OnError { exception -> // Handle errors } // Display the component (e.g., as dialog or full-screen overlay) } } override fun onOutgoingCallAccepted(call: Call) { // Handle accepted outgoing call } override fun onOutgoingCallRejected(call: Call) { // Handle rejected outgoing call } override fun onIncomingCallCancelled(call: Call) { // Handle cancelled incoming call } }) }}
class BaseApplication : Application() { companion object { private val LISTENER_ID = "${BaseApplication::class.java.simpleName}${System.currentTimeMillis()}" } override fun onCreate() { super.onCreate() CometChat.addCallListener(LISTENER_ID, object : CometChat.CallListener { override fun onIncomingCallReceived(call: Call) { CometChatCallActivity.launchIncomingCallScreen(this@BaseApplication, call, null) // Pass null or IncomingCallConfiguration if need to configure CometChatIncomingCall component } override fun onOutgoingCallAccepted(call: Call) { // Handle accepted outgoing call } override fun onOutgoingCallRejected(call: Call) { // Handle rejected outgoing call } override fun onIncomingCallCancelled(call: Call) { // Handle cancelled incoming call } }) }}
