# Request voice service state updates

This sample application demonstrates how to request voice service state corresponding to a SIM
in the device.

1. Implement ResponseCallback interface to receive subsystem initialization status

std::promise<telux::common::ServiceStatus> cbProm = std::promise<telux::common::ServiceStatus>();
    void initResponseCb(telux::common::ServiceStatus status) {
       if(subSystemsStatus == SERVICE_AVAILABLE) {
          std::cout << Phone Manager subsystem is ready << std::endl;
       } else if(subSystemsStatus == SERVICE_FAILED) {
          std::cout << Phone Manager subsystem initialization failed << std::endl;
       }
       cbProm.set_value(status);
    }
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2. Get the PhoneFactory and PhoneManager instance

auto &phoneFactory = PhoneFactory::getInstance();
    auto phoneManager = phoneFactory.getPhoneManager(initResponseCb);
    if(phoneManager == NULL) {
       std::cout << " Failed to get Phone Manager instance" << std::endl;
       return -1;
    }
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3. Wait for Phone Manager subsystem to be ready

telux::common::ServiceStatus status = cbProm.get_future().get();
    if(status != SERVICE_AVAILABLE) {
       std::cout << Unable to initialize Phone Manager subsystem << std::endl;
       return -1;
    }
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4. Get the phone object corresponding to a phone ID

auto phone = phoneManager->getPhone(DEFAULT_PHONE_ID);
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5. Implement IOperatingModeCallback interface and instantiate MyOperatingModeCallback

std::promise<bool> callbackPromise;
    telux::tel::OperatingMode operatingMode;
    class MyOperatingModeCallback : public telux::tel::IOperatingModeCallback {
    public:
       void operatingModeResponse(telux::tel::OperatingMode mode, telux::common::ErrorCode error) {
         if(error == telux::common::ErrorCode::SUCCESS) {
             std::cout << "Operating Mode is : " << static_cast<int>(mode)
                 << std::endl;
             operatingMode = static_cast<telux::tel::OperatingMode>(mode);
         } else {
             std::cout << "Operating Mode is : Unknown, errorCode: " << static_cast<int>(error)
             << std::endl;
         }
         callbackPromise.set_value(true);
       }
    };
    
    auto myOperatingModeCallback = std::make_shared<MyOperatingModeCallback>();
    
    void setOperatingModeResponse(telux::common::ErrorCode error) {
         std::cout << "Set Operating Mode is :, errorCode: " << static_cast<int>(error)
             << std::endl;
    }
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6. Request the operating mode of device and set the operating mode to ONLINE, if the operating mode is OFFLINE to perform any operations on the phone

phoneManager->requestOperatingMode(myOperatingModeCallback);
    if((callbackPromise.get_future().get()) &&
       (telux::tel::operatingMode == telux::tel::OperatingMode::OFFLINE )) {
       phoneManager->setOperatingMode(telux::tel::OperatingMode::ONLINE, &setOperatingModeResponse);
    }
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7. Implement IVoiceServiceStateCallback interface

class MyVoiceServiceStateCallback : public telux::tel::IVoiceServiceStateCallback {
    public:
       void voiceServiceStateResponse(const std::shared_ptr<telux::tel::VoiceServiceInfo> &serviceInfo, telux::common::ErrorCode error) override;
    };
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8. Instantiate MyVoiceServiceStateCallback

auto myVoiceServiceStateCallback = std::make_shared<MyVoiceServiceStateCallback>();
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9. Send voice service state request

phone->requestVoiceServiceState(myVoiceServiceStateCallback);
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After receiving voiceServiceStateResponse in MyVoiceServiceStateCallback, the status of voice registration can be accessed by using the VoiceServiceInfo.

Last Published: Jun 24, 2026

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