mainwindow.cpp Example File

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  ** This file is part of the examples of the QtSerialBus module.
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  #include "mainwindow.h"
  #include "ui_mainwindow.h"
  #include "connectdialog.h"

  #include <QCanBus>
  #include <QCanBusFrame>
  #include <QCloseEvent>
  #include <QDesktopServices>
  #include <QTimer>

  MainWindow::MainWindow(QWidget *parent) :
      QMainWindow(parent),
      m_ui(new Ui::MainWindow)
  {
      m_ui->setupUi(this);

      m_connectDialog = new ConnectDialog;

      m_status = new QLabel;
      m_ui->statusBar->addPermanentWidget(m_status);

      m_written = new QLabel;
      m_ui->statusBar->addWidget(m_written);

      initActionsConnections();
      QTimer::singleShot(50, m_connectDialog, &ConnectDialog::show);
  }

  MainWindow::~MainWindow()
  {
      delete m_canDevice;

      delete m_connectDialog;
      delete m_ui;
  }

  void MainWindow::initActionsConnections()
  {
      m_ui->actionDisconnect->setEnabled(false);
      m_ui->sendFrameBox->setEnabled(false);

      connect(m_ui->sendFrameBox, &SendFrameBox::sendFrame, this, &MainWindow::sendFrame);
      connect(m_ui->actionConnect, &QAction::triggered, m_connectDialog, &ConnectDialog::show);
      connect(m_connectDialog, &QDialog::accepted, this, &MainWindow::connectDevice);
      connect(m_ui->actionDisconnect, &QAction::triggered, this, &MainWindow::disconnectDevice);
      connect(m_ui->actionQuit, &QAction::triggered, this, &QWidget::close);
      connect(m_ui->actionAboutQt, &QAction::triggered, qApp, &QApplication::aboutQt);
      connect(m_ui->actionClearLog, &QAction::triggered, m_ui->receivedMessagesEdit, &QTextEdit::clear);
      connect(m_ui->actionPluginDocumentation, &QAction::triggered, this, []() {
          QDesktopServices::openUrl(QUrl("http://doc.qt.io/qt-5/qtcanbus-backends.html#can-bus-plugins"));
      });
  }

  void MainWindow::processErrors(QCanBusDevice::CanBusError error) const
  {
      switch (error) {
      case QCanBusDevice::ReadError:
      case QCanBusDevice::WriteError:
      case QCanBusDevice::ConnectionError:
      case QCanBusDevice::ConfigurationError:
      case QCanBusDevice::UnknownError:
          m_status->setText(m_canDevice->errorString());
          break;
      default:
          break;
      }
  }

  void MainWindow::connectDevice()
  {
      const ConnectDialog::Settings p = m_connectDialog->settings();

      QString errorString;
      m_canDevice = QCanBus::instance()->createDevice(p.pluginName, p.deviceInterfaceName,
                                                      &errorString);
      if (!m_canDevice) {
          m_status->setText(tr("Error creating device '%1', reason: '%2'")
                            .arg(p.pluginName).arg(errorString));
          return;
      }

      m_numberFramesWritten = 0;

      connect(m_canDevice, &QCanBusDevice::errorOccurred, this, &MainWindow::processErrors);
      connect(m_canDevice, &QCanBusDevice::framesReceived, this, &MainWindow::processReceivedFrames);
      connect(m_canDevice, &QCanBusDevice::framesWritten, this, &MainWindow::processFramesWritten);

      if (p.useConfigurationEnabled) {
          for (const ConnectDialog::ConfigurationItem &item : p.configurations)
              m_canDevice->setConfigurationParameter(item.first, item.second);
      }

      if (!m_canDevice->connectDevice()) {
          m_status->setText(tr("Connection error: %1").arg(m_canDevice->errorString()));

          delete m_canDevice;
          m_canDevice = nullptr;
      } else {
          m_ui->actionConnect->setEnabled(false);
          m_ui->actionDisconnect->setEnabled(true);

          m_ui->sendFrameBox->setEnabled(true);

          QVariant bitRate = m_canDevice->configurationParameter(QCanBusDevice::BitRateKey);
          if (bitRate.isValid()) {
              m_status->setText(tr("Plugin: %1, connected to %2 at %3 kBit/s")
                      .arg(p.pluginName).arg(p.deviceInterfaceName)
                      .arg(bitRate.toInt() / 1000));
          } else {
              m_status->setText(tr("Plugin: %1, connected to %2")
                      .arg(p.pluginName).arg(p.deviceInterfaceName));
          }
      }
  }

  void MainWindow::disconnectDevice()
  {
      if (!m_canDevice)
          return;

      m_canDevice->disconnectDevice();
      delete m_canDevice;
      m_canDevice = nullptr;

      m_ui->actionConnect->setEnabled(true);
      m_ui->actionDisconnect->setEnabled(false);

      m_ui->sendFrameBox->setEnabled(false);

      m_status->setText(tr("Disconnected"));
  }

  void MainWindow::processFramesWritten(qint64 count)
  {
      m_numberFramesWritten += count;
      m_written->setText(tr("%1 frames written").arg(m_numberFramesWritten));
  }

  void MainWindow::closeEvent(QCloseEvent *event)
  {
      m_connectDialog->close();
      event->accept();
  }

  static QString frameFlags(const QCanBusFrame &frame)
  {
      QString result = QLatin1String(" --- ");

      if (frame.hasBitrateSwitch())
          result[1] = QLatin1Char('B');
      if (frame.hasErrorStateIndicator())
          result[2] = QLatin1Char('E');
      if (frame.hasLocalEcho())
          result[3] = QLatin1Char('L');

      return result;
  }

  void MainWindow::processReceivedFrames()
  {
      if (!m_canDevice)
          return;

      while (m_canDevice->framesAvailable()) {
          const QCanBusFrame frame = m_canDevice->readFrame();

          QString view;
          if (frame.frameType() == QCanBusFrame::ErrorFrame)
              view = m_canDevice->interpretErrorFrame(frame);
          else
              view = frame.toString();

          const QString time = QString::fromLatin1("%1.%2  ")
                  .arg(frame.timeStamp().seconds(), 10, 10, QLatin1Char(' '))
                  .arg(frame.timeStamp().microSeconds() / 100, 4, 10, QLatin1Char('0'));

          const QString flags = frameFlags(frame);

          m_ui->receivedMessagesEdit->append(time + flags + view);
      }
  }

  void MainWindow::sendFrame(const QCanBusFrame &frame) const
  {
      if (!m_canDevice)
          return;

      m_canDevice->writeFrame(frame);
  }