Not putting my CsipSimple Voip call on hold when third party call pick

Question

I am develop a Voip Application using cSipSimple. now i want to show a busy tone when third party app call are coming (whatsapp, instagram and etc.)now the scenario is that i am on my voip call and some one call on my GSM number and i am picking up phone my voip call is automacitally going on to Hold but the next scenario is that when third party app calling and i am picking up that time my voip call is continue and third party call not working. now i want when third party app calling and i am picking up call my voip call putting on hold and i am connect with third party call. is there any method or receiver to detect third party call are coming??

i am try this How do I detect skype/telegram/whatsapp calls when my messenger app is in a call or wants to make a call? but its didn't work.

I am using this code for Detecting GSM Call and put my voip call on hold.

 public void onGSMStateChanged(int state, String incomingNumber) throws SameThreadException {
        // Avoid ringing if new GSM state is not idle
        if (state != TelephonyManager.CALL_STATE_IDLE && mediaManager != null) {
            mediaManager.stopRingAndUnfocus();
        }

        // If new call state is not idle
        if (state != TelephonyManager.CALL_STATE_IDLE && userAgentReceiver != null) {
            SipCallSession currentActiveCall = userAgentReceiver.getActiveCallOngoing();
            // If we have a sip call on our side
            if (currentActiveCall != null) {
                AudioManager am = (AudioManager) service.getSystemService(Context.AUDIO_SERVICE);
                if (state == TelephonyManager.CALL_STATE_OFFHOOK) {
                    // GSM is now off hook => hold current sip call
                    hasBeenHoldByGSM = currentActiveCall.getCallId();
                    callHold(hasBeenHoldByGSM);
                    pjsua.set_no_snd_dev();
                    am.setMode(AudioManager.MODE_IN_CALL);
                } else {
                    // We have a ringing incoming call.
                    // Avoid ringing
                    hasBeenChangedRingerMode = am.getRingerMode();
                    am.setRingerMode(AudioManager.RINGER_MODE_SILENT);
                    // And try to notify with tone
                    if (mediaManager != null) {
                        mediaManager.playInCallTone(MediaManager.TONE_CALL_WAITING);
                    }
                }
            }
        } else {
            // GSM is now back to an IDLE state, resume previously stopped SIP
            // calls
            if (hasBeenHoldByGSM != null && isCreated()) {
                pjsua.set_snd_dev(0, 0);
                callReinvite(hasBeenHoldByGSM, true);
                hasBeenHoldByGSM = null;
            }

            // GSM is now back to an IDLE state, reset ringerMode if was
            // changed.
            if (hasBeenChangedRingerMode != null) {
                AudioManager am = (AudioManager) service.getSystemService(Context.AUDIO_SERVICE);
                am.setRingerMode(hasBeenChangedRingerMode);
                hasBeenChangedRingerMode = null;
            }
        }
    }

Thanks in advance and help will be appreciate!!