Ignore sticky network intent.

android/src/main/scala/com/nutomic/ensichat/util/NetworkChangedReceiver.scala

@@ -1,11 +1,28 @@
 package com.nutomic.ensichat.util
 
 import android.content.{BroadcastReceiver, Context, Intent}
+import android.net.ConnectivityManager
 import com.nutomic.ensichat.service.ChatService
 
+/**
+ * Forwards network changed intents to [[ChatService]].
+ *
+ * HACK: Because [[ConnectivityManager.CONNECTIVITY_ACTION]] is a sticky intent, and we register it
+ *       from Scala, an intent is sent as soon as the receiver is registered. As a workaround, we
+ *       ignore the first intent received.
+ *       Alternatively, we can register the receiver in the manifest, but that will start the
+ *       service (so it only works if the service runs permanently, with no exit).
+ */
 class NetworkChangedReceiver extends BroadcastReceiver {
 
+  private var isFirstIntent = true
+
   override def onReceive(context: Context, intent: Intent): Unit = {
+    if (isFirstIntent) {
+      isFirstIntent = false
+      return
+    }
+
     val intent = new Intent(context, classOf[ChatService])
     intent.setAction(ChatService.ActionNetworkChanged)
     context.startService(intent)