Try to prevent crash seen in Crashlytics

app/src/main/java/org/linphone/core/CoreContext.kt

@@ -55,6 +55,10 @@ class CoreContext @UiThread constructor(val context: Context) : HandlerThread("C
 
     lateinit var core: Core
 
+    fun isCoreAvailable(): Boolean {
+        return ::core.isInitialized
+    }
+
     val contactsManager = ContactsManager()
 
     val notificationsManager = NotificationsManager(context)

app/src/main/java/org/linphone/core/CoreFileTransferService.kt

@@ -44,6 +44,8 @@ class CoreFileTransferService : FileTransferService() {
 
     var builder = NotificationCompat.Builder(this, SERVICE_NOTIFICATION_CHANNEL_ID)
 
+    var listenerAdded = false
+
     private val coreListener = object : CoreListenerStub() {
         @WorkerThread
         override fun onRemainingNumberOfFileTransferChanged(
@@ -57,12 +59,19 @@ class CoreFileTransferService : FileTransferService() {
 
     override fun onCreate() {
         super.onCreate()
-        coreContext.core.addListener(coreListener)
+        if (!listenerAdded && coreContext.isCoreAvailable()) {
+            coreContext.core.addListener(coreListener)
+            listenerAdded = true
+        }
         Log.i("$TAG Created")
     }
 
     override fun onStartCommand(intent: Intent?, flags: Int, startId: Int): Int {
         Log.i("$TAG onStartCommand")
+        if (!listenerAdded && coreContext.isCoreAvailable()) {
+            coreContext.core.addListener(coreListener)
+            listenerAdded = true
+        }
         return super.onStartCommand(intent, flags, startId)
     }
 
@@ -74,6 +83,7 @@ class CoreFileTransferService : FileTransferService() {
     override fun onDestroy() {
         Log.i("$TAG onDestroy")
         coreContext.core.removeListener(coreListener)
+        listenerAdded = false
         super.onDestroy()
     }
 

app/src/main/java/org/linphone/telecom/TelecomManager.kt

@@ -164,7 +164,7 @@ class TelecomManager @WorkerThread constructor(context: Context) {
                     Log.i("$TAG Call added to Telecom's CallsManager")
                 }
             } catch (e: Exception) {
-                Log.e("$TAG Failed to add call to Telecom's CallsManager!")
+                Log.e("$TAG Failed to add call to Telecom's CallsManager: $e")
             }
         }
     }