Android API: how to send empty sms with delivery report requirement?

Question

Android

Hello. I'm new to android coding. Killed the evening, did not find a way to resolve the issue.

Can you tell me how can I send an empty SMS requesting a delivery report?
Now only this without delivery report. And the problem is that you need to send an empty SMS. And if I replace "Test Message" with null or "", then the application crashes when sent. Thank you in advance.
SmsManager sm = SmsManager.getDefault();
sm.sendTextMessage(phoneNo, null, "Test Message", null, null);

Answer 1

Space? Or is it the lack of characters that is critical?

Answer 2

In the sendTextMessage method, there is such a check , so you can’t just send an empty message.
if (TextUtils.isEmpty(text)) {
throw new IllegalArgumentException("Invalid message body");
}