Qt 5.11 | Qt Bluetooth | Bluetooth Low Energy Heart Rate Game | devicefinder.cpp Example File

Qt 5.11.3 Reference Documentation

# devicefinder.cpp Example File

heartrate-game/devicefinder.cpp

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      ** This file is part of the examples of the QtBluetooth module of the Qt Toolkit.
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      #include "devicefinder.h"
      #include "devicehandler.h"
      #include "deviceinfo.h"

      DeviceFinder::DeviceFinder(DeviceHandler *handler, QObject *parent):
          BluetoothBaseClass(parent),
          m_deviceHandler(handler)
      {
          m_deviceDiscoveryAgent = new QBluetoothDeviceDiscoveryAgent(this);
          m_deviceDiscoveryAgent->setLowEnergyDiscoveryTimeout(5000);

          connect(m_deviceDiscoveryAgent, &QBluetoothDeviceDiscoveryAgent::deviceDiscovered, this, &DeviceFinder::addDevice);
          connect(m_deviceDiscoveryAgent, static_cast<void (QBluetoothDeviceDiscoveryAgent::*)(QBluetoothDeviceDiscoveryAgent::Error)>(&QBluetoothDeviceDiscoveryAgent::error),
                  this, &DeviceFinder::scanError);

          connect(m_deviceDiscoveryAgent, &QBluetoothDeviceDiscoveryAgent::finished, this, &DeviceFinder::scanFinished);
          connect(m_deviceDiscoveryAgent, &QBluetoothDeviceDiscoveryAgent::canceled, this, &DeviceFinder::scanFinished);

      #ifdef SIMULATOR
          m_demoTimer.setSingleShot(true);
          m_demoTimer.setInterval(2000);
          connect(&m_demoTimer, &QTimer::timeout, this, &DeviceFinder::scanFinished);
      #endif
      }

      DeviceFinder::~DeviceFinder()
      {
          qDeleteAll(m_devices);
          m_devices.clear();
      }

      void DeviceFinder::startSearch()
      {
          clearMessages();
          m_deviceHandler->setDevice(0);
          qDeleteAll(m_devices);
          m_devices.clear();

          emit devicesChanged();

      #ifdef SIMULATOR
          m_demoTimer.start();
      #else
          m_deviceDiscoveryAgent->start(QBluetoothDeviceDiscoveryAgent::LowEnergyMethod);
      #endif
          emit scanningChanged();
          setInfo(tr("Scanning for devices..."));
      }

      void DeviceFinder::addDevice(const QBluetoothDeviceInfo &device)
      {
          // If device is LowEnergy-device, add it to the list
          if (device.coreConfigurations() & QBluetoothDeviceInfo::LowEnergyCoreConfiguration) {
              m_devices.append(new DeviceInfo(device));
              setInfo(tr("Low Energy device found. Scanning more..."));
              emit devicesChanged();
          }
          //...
      }

      void DeviceFinder::scanError(QBluetoothDeviceDiscoveryAgent::Error error)
      {
          if (error == QBluetoothDeviceDiscoveryAgent::PoweredOffError)
              setError(tr("The Bluetooth adaptor is powered off."));
          else if (error == QBluetoothDeviceDiscoveryAgent::InputOutputError)
              setError(tr("Writing or reading from the device resulted in an error."));
          else
              setError(tr("An unknown error has occurred."));
      }

      void DeviceFinder::scanFinished()
      {
      #ifdef SIMULATOR
          // Only for testing
          for (int i = 0; i < 4; i++)
              m_devices.append(new DeviceInfo(QBluetoothDeviceInfo()));
      #endif

          if (m_devices.size() == 0)
              setError(tr("No Low Energy devices found."));
          else
              setInfo(tr("Scanning done."));

          emit scanningChanged();
          emit devicesChanged();
      }

      void DeviceFinder::connectToService(const QString &address)
      {
          m_deviceDiscoveryAgent->stop();

          DeviceInfo *currentDevice = 0;
          for (int i = 0; i < m_devices.size(); i++) {
              if (((DeviceInfo*)m_devices.at(i))->getAddress() == address ) {
                  currentDevice = (DeviceInfo*)m_devices.at(i);
                  break;
              }
          }

          if (currentDevice)
              m_deviceHandler->setDevice(currentDevice);

          clearMessages();
      }

      bool DeviceFinder::scanning() const
      {
      #ifdef SIMULATOR
          return m_demoTimer.isActive();
      #else
          return m_deviceDiscoveryAgent->isActive();
      #endif
      }

      QVariant DeviceFinder::devices()
      {
          return QVariant::fromValue(m_devices);
      }