How to prompt for sim selection before sending an SMS in dual sim phones using SMS manager programmatically?

Question

How to find SubscriptionId by prompting sim selection?

 SmsManager smsManager = null;
                   if (android.os.Build.VERSION.SDK_INT >= android.os.Build.VERSION_CODES.LOLLIPOP_MR1) {
                     smsManager = SmsManager.getSmsManagerForSubscriptionId();
                   }else{
                       smsManager = SmsManager.getDefault();
                   }`

subcription id needed inside getSmsManagerForSubscriptionId()

Answer 1

You can subscriptionManagerObj.getActiveSubscriptionInfoList() to get subscriptionIds based on Sim Slot. Based on the documentation

Get the SubscriptionInfo(s) of the currently inserted SIM(s). The records will be sorted by getSimSlotIndex() then by getSubscriptionId()

 SmsManager smsManager = null;
 if (android.os.Build.VERSION.SDK_INT >= android.os.Build.VERSION_CODES.LOLLIPOP_MR1) {

    SubscriptionManager subscriptionManager = (SubscriptionManager)getSystemService(Context.TELEPHONY_SUBSCRIPTION_SERVICE);
    List<SubscriptionInfo> subscriptionInfoList=subscriptionManager.getActiveSubscriptionInfoList();
    int subId = subscriptionInfoList.get(0).getSubscriptionId();// change index to 1 if you want to get Subscrption Id for slot 1.
    smsManager = SmsManager.getSmsManagerForSubscriptionId(subId);

 }else{
      smsManager = SmsManager.getDefault();
 }