Listen to all SMSes and do something when the definite message is received in Xamarin Android

Question

I want my android app to listen in all incoming messages and do what it is supposed to do when it receives the intended message. For example, I want to send the location of the phone to a preset number when it receives the message that the phone is missing, I do not care from which number it receives the message, only the message that will sent should be send to the specified number (for example my second number). I wrote the messaging codes and they are in the program and my only problem is receiving the messages and distinguishing them from each other and separating the correct message.

I apologize if my question is superficial or my explanation is inaccurate. I'm new in Xamarin and I have not become a professional yet. If the explanation is not complete, tell me where the problem is, I will explain more. Thanks

Answer 1

You could try to use BroadcastReceiver(android.provider.Telephony.SMS_RECEIVED) to listener the SMSes.

For more detail information, please refer to the official document: Broadcast Receivers in Xamarin.Android.

Something like:

[BroadcastReceiver(Enabled = true)]
[IntentFilter(new[] { "android.provider.Telephony.SMS_RECEIVED" })]
class SMSBroadcastReceiver: BroadcastReceiver
{
    public static string IntentAction = "android.provider.Telephony.SMS_RECEIVED";
    public override void OnReceive(Context context, Intent intent)
    {
       if (intent.Action != SmsRetriever.SmsRetrievedAction)
        return;

       var extrasBundleundle = intent.Extras;
       if (extrasBundleundle == null) return;
       var status = (Statuses)extrasBundleundle.Get(SmsRetriever.ExtraStatus);
       switch (status.StatusCode)
         {
            case CommonStatusCodes.Success:
            // Get SMS message contents
            var messageContent = (string)extrasBundleundle.Get(SmsRetriever.ExtraSmsMessage);
            
              break;

            case CommonStatusCodes.Timeout:
            
              break;
         }          
    }
}

don't forget to add the permission <uses-permission android:name=”android.permission.RECEIVE_SMS”/>