main.cpp Example File

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 #include <QtBluetooth/qlowenergyadvertisingdata.h>
 #include <QtBluetooth/qlowenergyadvertisingparameters.h>
 #include <QtBluetooth/qlowenergycharacteristic.h>
 #include <QtBluetooth/qlowenergycharacteristicdata.h>
 #include <QtBluetooth/qlowenergydescriptordata.h>
 #include <QtBluetooth/qlowenergycontroller.h>
 #include <QtBluetooth/qlowenergyservice.h>
 #include <QtBluetooth/qlowenergyservicedata.h>
 #include <QtCore/qbytearray.h>
 #include <QtCore/qcoreapplication.h>
 #include <QtCore/qlist.h>
 #include <QtCore/qloggingcategory.h>
 #include <QtCore/qscopedpointer.h>
 #include <QtCore/qtimer.h>

 int main(int argc, char *argv[])
 {
     //QLoggingCategory::setFilterRules(QStringLiteral("qt.bluetooth* = true"));
     QCoreApplication app(argc, argv);

     QLowEnergyAdvertisingData advertisingData;
     advertisingData.setDiscoverability(QLowEnergyAdvertisingData::DiscoverabilityGeneral);
     advertisingData.setIncludePowerLevel(true);
     advertisingData.setLocalName("HeartRateServer");
     advertisingData.setServices(QList<QBluetoothUuid>() << QBluetoothUuid::HeartRate);

     QLowEnergyCharacteristicData charData;
     charData.setUuid(QBluetoothUuid::HeartRateMeasurement);
     charData.setValue(QByteArray(2, 0));
     charData.setProperties(QLowEnergyCharacteristic::Notify);
     const QLowEnergyDescriptorData clientConfig(QBluetoothUuid::ClientCharacteristicConfiguration,
                                                 QByteArray(2, 0));
     charData.addDescriptor(clientConfig);

     QLowEnergyServiceData serviceData;
     serviceData.setType(QLowEnergyServiceData::ServiceTypePrimary);
     serviceData.setUuid(QBluetoothUuid::HeartRate);
     serviceData.addCharacteristic(charData);

     const QScopedPointer<QLowEnergyController> leController(QLowEnergyController::createPeripheral());
     QScopedPointer<QLowEnergyService> service(leController->addService(serviceData));
     leController->startAdvertising(QLowEnergyAdvertisingParameters(), advertisingData,
                                    advertisingData);

     QTimer heartbeatTimer;
     quint8 currentHeartRate = 60;
     enum ValueChange { ValueUp, ValueDown } valueChange = ValueUp;
     const auto heartbeatProvider = [&service, &currentHeartRate, &valueChange]() {
         QByteArray value;
         value.append(char(0)); // Flags that specify the format of the value.
         value.append(char(currentHeartRate)); // Actual value.
         QLowEnergyCharacteristic characteristic
                 = service->characteristic(QBluetoothUuid::HeartRateMeasurement);
         Q_ASSERT(characteristic.isValid());
         service->writeCharacteristic(characteristic, value); // Potentially causes notification.
         if (currentHeartRate == 60)
             valueChange = ValueUp;
         else if (currentHeartRate == 100)
             valueChange = ValueDown;
         if (valueChange == ValueUp)
             ++currentHeartRate;
         else
             --currentHeartRate;
     };
     QObject::connect(&heartbeatTimer, &QTimer::timeout, heartbeatProvider);
     heartbeatTimer.start(1000);

     auto reconnect = [&leController, advertisingData, &service, serviceData]()
     {
         service.reset(leController->addService(serviceData));
         if (!service.isNull())
             leController->startAdvertising(QLowEnergyAdvertisingParameters(),
                                            advertisingData, advertisingData);
     };
     QObject::connect(leController.data(), &QLowEnergyController::disconnected, reconnect);

     return app.exec();
 }