ui->plotToolBar->addAction(snapshotMan.takeSnapshotAction());

    ui->menuBar->insertMenu(ui->menuHelp->menuAction(), snapshotMan.menu());

    ui->menuBar->insertMenu(ui->menuHelp->menuAction(), commandPanel.menu());

    connect(commandPanel.newCommandAction(), &QAction::triggered, [this]()

            {

                this->ui->tabWidget->setCurrentWidget(&commandPanel);

            });

    setupAboutDialog();

    // init view menu

    for (auto a : ui->plot->menuActions())

    {

        ui->menuView->addAction(a);

    }

    ui->menuView->addSeparator();

    QMenu* tbMenu = ui->menuView->addMenu("Toolbars");

    tbMenu->addAction(ui->plotToolBar->toggleViewAction());

    tbMenu->addAction(portControl.toolBar()->toggleViewAction());

    // init UI signals

    // menu signals

    QObject::connect(ui->actionHelpAbout, &QAction::triggered,

              &aboutDialog, &QWidget::show);

    QObject::connect(ui->actionExportCsv, &QAction::triggered,

                     this, &MainWindow::onExportCsv);

    ui->actionQuit->setShortcutContext(Qt::ApplicationShortcut);

    QObject::connect(ui->actionQuit, &QAction::triggered,

                     this, &MainWindow::close);

    // port control signals

    QObject::connect(&portControl, &PortControl::portToggled,

                     this, &MainWindow::onPortToggled);

    QObject::connect(&portControl, &PortControl::skipByteRequested,

                     &dataFormatPanel, &DataFormatPanel::requestSkipByte);

    QObject::connect(ui->spNumOfSamples, SELECT<int>::OVERLOAD_OF(&QSpinBox::valueChanged),

                     this, &MainWindow::onNumOfSamplesChanged);

    QObject::connect(ui->cbAutoScale, &QCheckBox::toggled,

                     this, &MainWindow::onAutoScaleChecked);

    QObject::connect(ui->spYmin, SIGNAL(valueChanged(double)),

                     this, SLOT(onYScaleChanged()));

    QObject::connect(ui->spYmax, SIGNAL(valueChanged(double)),

                     this, SLOT(onYScaleChanged()));

    QObject::connect(ui->actionClear, SIGNAL(triggered(bool)),

                     this, SLOT(clearPlot()));

    QObject::connect(snapshotMan.takeSnapshotAction(), &QAction::triggered,

                     ui->plot, &Plot::flashSnapshotOverlay);

    // init port signals

    QObject::connect(&(this->serialPort), SIGNAL(error(QSerialPort::SerialPortError)),

                     this, SLOT(onPortError(QSerialPort::SerialPortError)));

    // set limits for axis limit boxes

    ui->spYmin->setRange((-1) * std::numeric_limits<double>::max(),

                         std::numeric_limits<double>::max());

    ui->spYmax->setRange((-1) * std::numeric_limits<double>::max(),

                         std::numeric_limits<double>::max());

    // init data format and reader

    QObject::connect(&dataFormatPanel, &DataFormatPanel::dataAdded,

                     ui->plot, &QwtPlot::replot);

    QObject::connect(ui->actionPause, &QAction::triggered,

                     &dataFormatPanel, &DataFormatPanel::pause);

    // init data arrays and plot

    numOfSamples = ui->spNumOfSamples->value();

    unsigned numOfChannels = dataFormatPanel.numOfChannels();

    channelMan.setNumOfSamples(ui->spNumOfSamples->value());

    channelMan.setNumOfChannels(dataFormatPanel.numOfChannels());

    connect(&dataFormatPanel, &DataFormatPanel::numOfChannelsChanged,

            &channelMan, &ChannelManager::setNumOfChannels);

    connect(&channelMan, &ChannelManager::numOfChannelsChanged,

            this, &MainWindow::onNumOfChannelsChanged);

    connect(&channelMan, &ChannelManager::channelNameChanged,

            this, &MainWindow::onChannelNameChanged);

    for (unsigned int i = 0; i < numOfChannels; i++)

    {

        curves.append(new QwtPlotCurve(channelMan.channelName(i)));

        curves[i]->setSamples(channelMan.channelBuffer(i));

        curves[i]->setPen(Plot::makeColor(i));

        curves[i]->attach(ui->plot);

    }

    // init auto scale

    ui->plot->setAxis(ui->cbAutoScale->isChecked(),

                      ui->spYmin->value(), ui->spYmax->value());

    // init scale range preset list

    for (int nbits = 8; nbits <= 24; nbits++) // signed binary formats

    {

        int rmax = pow(2, nbits-1)-1;

        int rmin = -rmax-1;

        Range r = {double(rmin),  double(rmax)};

        ui->cbRangePresets->addItem(

            QString().sprintf("Signed %d bits %d to +%d", nbits, rmin, rmax),

            QVariant::fromValue(r));

    }

    for (int nbits = 8; nbits <= 24; nbits++) // unsigned binary formats

    {

        int rmax = pow(2, nbits)-1;

        ui->cbRangePresets->addItem(

            QString().sprintf("Unsigned %d bits %d to +%d", nbits, 0, rmax),

            QVariant::fromValue(Range{0, double(rmax)}));

    }

    ui->cbRangePresets->addItem("-1 to +1", QVariant::fromValue(Range{-1, +1}));

    ui->cbRangePresets->addItem("0 to +1", QVariant::fromValue(Range{0, +1}));

    ui->cbRangePresets->addItem("-100 to +100", QVariant::fromValue(Range{-100, +100}));

    ui->cbRangePresets->addItem("0 to +100", QVariant::fromValue(Range{0, +100}));

    QObject::connect(ui->cbRangePresets, SIGNAL(activated(int)),

                     this, SLOT(onRangeSelected()));

    // Init sps (sample per second) counter

    spsLabel.setText("0sps");

    spsLabel.setToolTip("samples per second (total of all channels)");

    ui->statusBar->addPermanentWidget(&spsLabel);

    QObject::connect(&dataFormatPanel,

                     &DataFormatPanel::samplesPerSecondChanged,

                     this, &MainWindow::onSpsChanged);

    // init demo

    QObject::connect(ui->actionDemoMode, &QAction::toggled,

                     this, &MainWindow::enableDemo);

    {   // init demo indicator

        QwtText demoText(" DEMO RUNNING ");  // looks better with spaces

        demoText.setColor(QColor("white"));

        demoText.setBackgroundBrush(Qt::darkRed);

        demoText.setBorderRadius(4);

        demoText.setRenderFlags(Qt::AlignLeft | Qt::AlignTop);

        demoIndicator.setText(demoText);

        demoIndicator.hide();

        demoIndicator.attach(ui->plot);

    }

}

MainWindow::~MainWindow()

{

    for (auto curve : curves)

    {

        // also deletes respective FrameBuffer

        delete curve;

    }

    if (serialPort.isOpen())

    {

        serialPort.close();

    }

    delete ui;

    ui = NULL; // we check if ui is deleted in messageHandler

}

void MainWindow::setupAboutDialog()

{

    Ui_AboutDialog uiAboutDialog;

    uiAboutDialog.setupUi(&aboutDialog);

    QObject::connect(uiAboutDialog.pbAboutQt, &QPushButton::clicked,

                     [](){ QApplication::aboutQt();});

    QString aboutText = uiAboutDialog.lbAbout->text();

    aboutText.replace("$VERSION_STRING$", VERSION_STRING);

    aboutText.replace("$VERSION_REVISION$", VERSION_REVISION);

    uiAboutDialog.lbAbout->setText(aboutText);

}

void MainWindow::onPortToggled(bool open)

{

    // make sure demo mode is disabled

    if (open && isDemoRunning()) enableDemo(false);

<?xml version="1.0" encoding="UTF-8"?>

<ui version="4.0">

 <class>MainWindow</class>

 <widget class="QMainWindow" name="MainWindow">

  <property name="geometry">

   <rect>

    <x>0</x>

    <y>0</y>

    <width>653</width>

    <height>534</height>

   </rect>

  </property>

  <property name="windowTitle">

   <string>SerialPlot</string>

  </property>

  <widget class="QWidget" name="centralWidget">

   <layout class="QVBoxLayout" name="verticalLayout_2">

    <item>

     <widget class="Plot" name="plot" native="true">

      <property name="sizePolicy">

       <sizepolicy hsizetype="Preferred" vsizetype="Expanding">

        <horstretch>0</horstretch>

        <verstretch>0</verstretch>

       </sizepolicy>

      </property>

     </widget>

    </item>

    <item>

     <widget class="HidableTabWidget" name="tabWidget">

      <property name="sizePolicy">

       <sizepolicy hsizetype="Expanding" vsizetype="Minimum">

        <horstretch>0</horstretch>

        <verstretch>0</verstretch>

       </sizepolicy>

      </property>

      <property name="minimumSize">

       <size>

        <width>0</width>

        <height>0</height>

       </size>

      </property>

      <property name="maximumSize">

       <size>

        <width>16777215</width>

        <height>16777215</height>

       </size>

      </property>

      <property name="currentIndex">

       <number>0</number>

      </property>

      <property name="movable">

       <bool>false</bool>

      </property>

      <widget class="QWidget" name="tabPlot">

       <attribute name="title">

        <string>Plot</string>

       </attribute>

       <layout class="QHBoxLayout" name="horizontalLayout_4">

        <item>

          </property>

          </property>

        </item>

        <item>

         <widget class="Line" name="line">

          <property name="orientation">

           <enum>Qt::Vertical</enum>

          </property>

         </widget>

        </item>

        <item>

         <layout class="QFormLayout" name="formLayout_2">

          <property name="fieldGrowthPolicy">

           <enum>QFormLayout::AllNonFixedFieldsGrow</enum>

          </property>

          <item row="0" column="0">

           <widget class="QLabel" name="label_3">

            <property name="text">

             <string>Number Of Samples:</string>

            </property>

           </widget>

          </item>

          <item row="0" column="1">

           <widget class="QSpinBox" name="spNumOfSamples">

            <property name="toolTip">

             <string>length of X axis</string>

            </property>

            <property name="keyboardTracking">

             <bool>false</bool>

            </property>

            <property name="minimum">

             <number>2</number>

            </property>

            <property name="maximum">

             <number>10000</number>

            </property>

            <property name="value">

             <number>1000</number>

            </property>

           </widget>

          </item>

          <item row="1" column="0">

           <widget class="QCheckBox" name="cbAutoScale">

            <property name="text">

             <string>Auto Scale Y Axis</string>

            </property>

            <property name="checked">

             <bool>true</bool>

            </property>

           </widget>

          </item>

          <item row="2" column="0">

           <widget class="QLabel" name="lYmax">

            <property name="enabled">

             <bool>false</bool>

            </property>

            <property name="text">

             <string>Ymax</string>

            </property>

           </widget>

          </item>

          <item row="2" column="1">

           <widget class="QDoubleSpinBox" name="spYmax">

            <property name="enabled">

             <bool>false</bool>

            </property>

            <property name="maximumSize">

             <size>

              <width>75</width>

              <height>16777215</height>

             </size>

            </property>

            <property name="toolTip">

             <string>upper limit of Y axis</string>

            </property>

            <property name="maximum">

             <double>1000.000000000000000</double>

            </property>

            <property name="value">

             <double>1000.000000000000000</double>

            </property>

           </widget>

          </item>

          <item row="3" column="0">

           <widget class="QLabel" name="lYmin">

            <property name="enabled">

             <bool>false</bool>

            </property>

            <property name="text">

             <string>Ymin</string>

            </property>

           </widget>

          </item>

          <item row="3" column="1">

           <widget class="QDoubleSpinBox" name="spYmin">

            <property name="enabled">

             <bool>false</bool>

            </property>