Qt 5.9 | Qt Bluetooth | Bluetooth Low Energy Heart Rate Game | devicefinder.cpp Example File

Qt 5.9.9 Reference Documentation

# devicefinder.cpp Example File

heartrate-game/devicefinder.cpp

      /***************************************************************************
      **
      ** Copyright (C) 2017 The Qt Company Ltd.
      ** Contact: https://www.qt.io/licensing/
      **
      ** This file is part of the examples of the QtBluetooth module of the Qt Toolkit.
      **
      ** $QT_BEGIN_LICENSE:BSD$
      ** Commercial License Usage
      ** Licensees holding valid commercial Qt licenses may use this file in
      ** accordance with the commercial license agreement provided with the
      ** Software or, alternatively, in accordance with the terms contained in
      ** a written agreement between you and The Qt Company. For licensing terms
      ** and conditions see https://www.qt.io/terms-conditions. For further
      ** information use the contact form at https://www.qt.io/contact-us.
      **
      ** BSD License Usage
      ** Alternatively, you may use this file under the terms of the BSD license
      ** as follows:
      **
      ** "Redistribution and use in source and binary forms, with or without
      ** modification, are permitted provided that the following conditions are
      ** met:
      **   * Redistributions of source code must retain the above copyright
      **     notice, this list of conditions and the following disclaimer.
      **   * Redistributions in binary form must reproduce the above copyright
      **     notice, this list of conditions and the following disclaimer in
      **     the documentation and/or other materials provided with the
      **     distribution.
      **   * Neither the name of The Qt Company Ltd nor the names of its
      **     contributors may be used to endorse or promote products derived
      **     from this software without specific prior written permission.
      **
      **
      ** THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
      ** "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
      ** LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
      ** A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
      ** OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
      ** SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
      ** LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
      ** DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
      ** THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
      ** (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
      ** OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE."
      **
      ** $QT_END_LICENSE$
      **
      ****************************************************************************/

      #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);
      }