Option to send sms using Sim1 or Sim2 programmatically

If you can use this code for API level 22+.

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();    }}

Also add permission.

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

SmsManager.getSmsManagerForSubscriptionId(int subscriptionId).sendTextMessage(String destinationAddress, String scAddress, String text,PendingIntent sentIntent, PendingIntent deliveryIntent);

this can be working after 5.1 Lollipop version.before that we need to see more. once i got the answer i will update.

You should check out tasker, you would be able to user it to build a toggle widget for that.