Question

I am currently trying to develop an SMS application and allow a user to send SMS to multiple people.

As the SMS is long i have to use the sendMultipartTextMessage which is below

private void sendSMS(final String phoneNumber, String message) {
    String SENT = "SMS_SENT";
    String DELIVERED = "SMS_DELIVERED";

    SmsManager sms = SmsManager.getDefault();
    ArrayList<String> parts = sms.divideMessage(message);
    int messageCount = parts.size();

    Log.i("Message Count", "Message Count: " + messageCount);

    ArrayList<PendingIntent> deliveryIntents = new ArrayList<PendingIntent>();
    ArrayList<PendingIntent> sentIntents = new ArrayList<PendingIntent>();

    PendingIntent sentPI = PendingIntent.getBroadcast(this, 0, new Intent(SENT), 0);
    PendingIntent deliveredPI = PendingIntent.getBroadcast(this, 0, new Intent(DELIVERED), 0);

    for (int j = 0; j < messageCount; j++) {
        sentIntents.add(sentPI);
        deliveryIntents.add(deliveredPI);
    }

    // ---when the SMS has been sent---
    registerReceiver(new BroadcastReceiver() {
        @Override
        public void onReceive(Context arg0, Intent arg1) {
            switch (getResultCode()) {
            case Activity.RESULT_OK:
                Toast.makeText(getBaseContext(), "SMS sent",
                        Toast.LENGTH_SHORT).show();
                break;
            case SmsManager.RESULT_ERROR_GENERIC_FAILURE:
                Toast.makeText(getBaseContext(), "Generic failure",
                        Toast.LENGTH_SHORT).show();
                break;
            case SmsManager.RESULT_ERROR_NO_SERVICE:
                Toast.makeText(getBaseContext(), "No service",
                        Toast.LENGTH_SHORT).show();
                break;
            case SmsManager.RESULT_ERROR_NULL_PDU:
                Toast.makeText(getBaseContext(), "Null PDU",
                        Toast.LENGTH_SHORT).show();
                break;
            case SmsManager.RESULT_ERROR_RADIO_OFF:
                Toast.makeText(getBaseContext(), "Radio off",
                        Toast.LENGTH_SHORT).show();
                break;
            }
        }
    }, new IntentFilter(SENT));

    // ---when the SMS has been delivered---
    registerReceiver(new BroadcastReceiver() {
        @Override
        public void onReceive(Context arg0, Intent arg1) {
            switch (getResultCode()) {

            case Activity.RESULT_OK:
                Toast.makeText(getBaseContext(), "SMS delivered",
                        Toast.LENGTH_SHORT).show();
                break;
            case Activity.RESULT_CANCELED:
                Toast.makeText(getBaseContext(), "SMS not delivered",
                        Toast.LENGTH_SHORT).show();
                break;
            }
        }
    }, new IntentFilter(DELIVERED));

    sms.sendMultipartTextMessage(phoneNumber, null, parts, sentIntents, deliveryIntents);
}

I will encounter a generic error when i attempt to send it to multiple people in a loop like this and the message won’t be sent. I’m suspecting it is because the message is probably 3-4 parts and the android system cannot send the message in time even with the 3000 milliseconds delay.

    for (int t = 0; t < array.length; t++) {
        System.out.println("temp: " + array[t].toString());
        try {
            sendSMS(array[t].toString(), message);
            Thread.sleep(3000);
        } catch (InterruptedException e) {
            e.printStackTrace();
        }
    }

EDIT: The above code are in a AsyncTask which is executed inside a Service.

Answer 1

IHMO you are not using the right approach. I’m using a different one and it is working. I try to explain:

You should keep a counter for all pending intents because if the sms you are sending has two parts you will receive two RESULT_OK (or RESULT_ERROR_*) and only when you receive the results for all parts you should proceed sending the next sms. I don’t like the idea of blocking the thread… maybe this is the reason you are getting strange errors.

I refactored your code with my approach:

private int mMessageSentParts;
private int mMessageSentTotalParts;
private int mMessageSentCount;

private void startSendMessages(){

    registerBroadCastReceivers();

    mMessageSentCount = 0;
    sendSMS(array[mMessageSentCount].toString(), message);
}

private void sendNextMessage(){
    if(thereAreSmsToSend()){
        sendSMS(array[mMessageSentCount].toString(), message);
    }else{
        Toast.makeText(getBaseContext(), "All SMS have been sent",
                        Toast.LENGTH_SHORT).show();
    }
}

private boolean thereAreSmsToSend(){
    return mMessageSentCount < array.length;
}

private void sendSMS(final String phoneNumber, String message) {
    String SENT = "SMS_SENT";
    String DELIVERED = "SMS_DELIVERED";

    SmsManager sms = SmsManager.getDefault();
    ArrayList<String> parts = sms.divideMessage(message);
    mMessageSentTotalParts = parts.size();

    Log.i("Message Count", "Message Count: " + mMessageSentTotalParts);

    ArrayList<PendingIntent> deliveryIntents = new ArrayList<PendingIntent>();
    ArrayList<PendingIntent> sentIntents = new ArrayList<PendingIntent>();

    PendingIntent sentPI = PendingIntent.getBroadcast(this, 0, new Intent(SENT), 0);
    PendingIntent deliveredPI = PendingIntent.getBroadcast(this, 0, new Intent(DELIVERED), 0);

    for (int j = 0; j < mMessageSentTotalParts; j++) {
        sentIntents.add(sentPI);
        deliveryIntents.add(deliveredPI);
    }

    mMessageSentParts = 0;
    sms.sendMultipartTextMessage(phoneNumber, null, parts, sentIntents, deliveryIntents);
}

private void registerBroadCastReceivers(){

    registerReceiver(new BroadcastReceiver() {
        @Override
        public void onReceive(Context arg0, Intent arg1) {
            switch (getResultCode()) {
            case Activity.RESULT_OK:

                mMessageSentParts++;
                if ( mMessageSentParts == mMessageSentTotalParts ) {
                    mMessageSentCount++;
                    sendNextMessage();
                }

                Toast.makeText(getBaseContext(), "SMS sent",
                        Toast.LENGTH_SHORT).show();
                break;
            case SmsManager.RESULT_ERROR_GENERIC_FAILURE:
                Toast.makeText(getBaseContext(), "Generic failure",
                        Toast.LENGTH_SHORT).show();
                break;
            case SmsManager.RESULT_ERROR_NO_SERVICE:
                Toast.makeText(getBaseContext(), "No service",
                        Toast.LENGTH_SHORT).show();
                break;
            case SmsManager.RESULT_ERROR_NULL_PDU:
                Toast.makeText(getBaseContext(), "Null PDU",
                        Toast.LENGTH_SHORT).show();
                break;
            case SmsManager.RESULT_ERROR_RADIO_OFF:
                Toast.makeText(getBaseContext(), "Radio off",
                        Toast.LENGTH_SHORT).show();
                break;
            }
        }
    }, new IntentFilter(SENT));

    registerReceiver(new BroadcastReceiver() {
        @Override
        public void onReceive(Context arg0, Intent arg1) {
            switch (getResultCode()) {

            case Activity.RESULT_OK:
                Toast.makeText(getBaseContext(), "SMS delivered",
                        Toast.LENGTH_SHORT).show();
                break;
            case Activity.RESULT_CANCELED:
                Toast.makeText(getBaseContext(), "SMS not delivered",
                        Toast.LENGTH_SHORT).show();
                break;
            }
        }
    }, new IntentFilter(DELIVERED));

}