How is it possible to do USSD requests on Android?

Question

Some custom dialer apps (for example, Dialer from MotoBlur) are able to do USSD requests. Is it realy impossible to do this via SDK?

Answer 1

Ussd api was added in API26. So since Oreo working with ussd looks smt like this:

    TelephonyManager manager = (TelephonyManager)getSystemService(TELEPHONY_SERVICE);
    manager.sendUssdRequest("*100#", new TelephonyManager.UssdResponseCallback() {
        @Override
        public void onReceiveUssdResponse(TelephonyManager telephonyManager, String request, CharSequence response) {
            super.onReceiveUssdResponse(telephonyManager, request, response);
        }

        @Override
        public void onReceiveUssdResponseFailed(TelephonyManager telephonyManager, String request, int failureCode) {
            super.onReceiveUssdResponseFailed(telephonyManager, request, failureCode);
        }
    }, new Handler());

    TelephonyManager manager2 = manager.createForSubscriptionId(subIdForSecondSlotFromSubscriptonManager);
    manager2.sendUssdRequest(...);

To get the simIDs, you can use the below:

    SubscriptionManager subscriptionManager = (SubscriptionManager) getSystemService(Context.TELEPHONY_SUBSCRIPTION_SERVICE);

    List<SubscriptionInfo> subscriptionInfoList = subscriptionManager.getActiveSubscriptionInfoList();

    for (SubscriptionInfo subscriptionInfo : subscriptionInfoList) {
        int subscriptionId = subscriptionInfo.getSubscriptionId();
        Log.d("Sims", "subscriptionId:" + subscriptionId);
    }

    if (subscriptionInfoList != null) {
        if (subscriptionInfoList.size() == 1) {
            sim1 = subscriptionInfoList.get(0).getDisplayName().toString();
            tvSim1.setText(sim1);
        } else {
            sim1 = subscriptionInfoList.get(0).getDisplayName().toString();
            sim2 = subscriptionInfoList.get(1).getDisplayName().toString();

            tvSim1.setText(sim1);
            tvSim2.setText(sim2);
        }

    }

Answer 2

You can intercept the USSD reponse , In order to do that you need to implement IExtendedNetworkService.aidl interface which binds the service with PhoneUtils. It then can intercept any USSD response and you can read that in your app easily . FYI https://github.com/alaasalman/ussdinterceptor

Answer 3

You can dial ussd requests like any other number with an call-intent like this one:

String encodedHash = Uri.encode("#");
String ussd = "*" + encodedHash + "12345" + encodedHash;
startActivityForResult(new Intent("android.intent.action.CALL", Uri.parse("tel:" + ussd)), 1);

However, afaik, it's currently not possible to parse the result string in your app.