Option to send sms using Sim1 or Sim2 programmatically

You can use this code for API level 22+ (Android 5.0) LOLLIPOP_MR1.

private void sendDirectSMS() {

    private static String SENT = "SMS_SENT", DELIVERED = "SMS_DELIVERED";

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

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

    // SEND BroadcastReceiver
    BroadcastReceiver sendSMS = new BroadcastReceiver() {
        @Override
        public void onReceive(Context arg0, Intent arg1) {
            switch (getResultCode()) {
                case Activity.RESULT_OK:
                    showSnackBar(getString(R.string.sms_sent));
                    Analytics.track(AnalyticsEvents.SEND_REMINDER_SMS_APP_SUCCESS);
                    break;
                case SmsManager.RESULT_ERROR_GENERIC_FAILURE:
                    showSnackBar(getString(R.string.sms_send_failed_try_again));
                    Analytics.track(AnalyticsEvents.SEND_REMINDER_SMS_APP_FAILED);
                    break;
                case SmsManager.RESULT_ERROR_NO_SERVICE:
                    showSnackBar(getString(R.string.no_service_sms_failed));
                    Analytics.track(AnalyticsEvents.SEND_REMINDER_SMS_APP_FAILED);
                    break;
                case SmsManager.RESULT_ERROR_NULL_PDU:
                    showSnackBar(getString(R.string.no_service_sms_failed));
                    Analytics.track(AnalyticsEvents.SEND_REMINDER_SMS_APP_FAILED);
                    break;
                case SmsManager.RESULT_ERROR_RADIO_OFF:
                    showSnackBar(getString(R.string.no_service_sms_failed));
                    Analytics.track(AnalyticsEvents.SEND_REMINDER_SMS_APP_FAILED);
                    break;
            }
        }
    };

    // DELIVERY BroadcastReceiver
    BroadcastReceiver deliverSMS = new BroadcastReceiver() {
        @Override
        public void onReceive(Context arg0, Intent arg1) {
            switch (getResultCode()) {
                case Activity.RESULT_OK:
                    Toast.makeText(getBaseContext(), R.string.sms_delivered,
                        Toast.LENGTH_SHORT).show();
                    break;
                case Activity.RESULT_CANCELED:
                    Toast.makeText(getBaseContext(), R.string.sms_not_delivered,
                        Toast.LENGTH_SHORT).show();
                    break;
            }
        }
    };

    registerReceiver(sendSMS, new IntentFilter(SENT));
    registerReceiver(deliverSMS, new IntentFilter(DELIVERED));
    String smsText = getSmsText();

    if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.LOLLIPOP_MR1) {
        SubscriptionManager localSubscriptionManager = SubscriptionManager.from(context);
        if (localSubscriptionManager.getActiveSubscriptionInfoCount() > 1) {
            List localList = localSubscriptionManager.getActiveSubscriptionInfoList();

            SubscriptionInfo simInfo1 = (SubscriptionInfo) localList.get(0);
            SubscriptionInfo simInfo2 = (SubscriptionInfo) localList.get(1);

            //SendSMS From SIM One
            SmsManager.getSmsManagerForSubscriptionId(simInfo1.getSubscriptionId()).sendTextMessage(customer.getMobile(), null, smsText, sentPI, deliveredPI);

            //SendSMS From SIM Two
            SmsManager.getSmsManagerForSubscriptionId(simInfo2.getSubscriptionId()).sendTextMessage(customer.getMobile(), null, smsText, sentPI, deliveredPI);
        }
    } else {
        SmsManager.getDefault().sendTextMessage(customer.getMobile(), null, smsText, sentPI, deliveredPI);
        Toast.makeText(getBaseContext(), R.string.sms_sending, Toast.LENGTH_SHORT).show();
    }
}

Don’t forget to add permission in your AndoridManifest.xml.

<uses-permission android:name="android.permission.SEND_SMS"/>
<uses-permission android:name="android.permission.READ_PHONE_STATE"/>