addPlotWidget();

    // initialize menu actions

    showGridAction.setToolTip("Show Grid");

    showMinorGridAction.setToolTip("Show Minor Grid");

    unzoomAction.setToolTip("Unzoom the Plot");

    darkBackgroundAction.setToolTip("Enable Dark Plot Background");

    showLegendAction.setToolTip("Display the Legend on Plot");

    showMultiAction.setToolTip("Display All Channels Separately");

    showGridAction.setShortcut(QKeySequence("G"));

    showMinorGridAction.setShortcut(QKeySequence("M"));

    showGridAction.setCheckable(true);

    showMinorGridAction.setCheckable(true);

    darkBackgroundAction.setCheckable(true);

    showLegendAction.setCheckable(true);

    showMultiAction.setCheckable(true);

    showGridAction.setChecked(false);

    showMinorGridAction.setChecked(false);

    darkBackgroundAction.setChecked(false);

    showLegendAction.setChecked(true);

    showMultiAction.setChecked(false);

    showMinorGridAction.setEnabled(false);

    connect(&showGridAction, SELECT<bool>::OVERLOAD_OF(&QAction::triggered),

            this, &PlotManager::showGrid);

    connect(&showGridAction, SELECT<bool>::OVERLOAD_OF(&QAction::triggered),

            &showMinorGridAction, &QAction::setEnabled);

    connect(&showMinorGridAction, SELECT<bool>::OVERLOAD_OF(&QAction::triggered),

            this, &PlotManager::showMinorGrid);

    connect(&unzoomAction, &QAction::triggered, this, &PlotManager::unzoom);

    connect(&darkBackgroundAction, SELECT<bool>::OVERLOAD_OF(&QAction::triggered),

            this, &PlotManager::darkBackground);

    connect(&showLegendAction, SELECT<bool>::OVERLOAD_OF(&QAction::triggered),

            this, &PlotManager::showLegend);

    connect(&showLegendAction, SELECT<bool>::OVERLOAD_OF(&QAction::triggered),

            this, &PlotManager::showLegend);

    connect(&showMultiAction, SELECT<bool>::OVERLOAD_OF(&QAction::triggered),

            this, &PlotManager::setMulti);

    // connect to channel info model

    if (_infoModel != NULL)     // TODO: remove when snapshots have infomodel

    {

        connect(_infoModel, &QAbstractItemModel::dataChanged,

                this, &PlotManager::onChannelInfoChanged);

    }

}

PlotManager::~PlotManager()

{

    while (curves.size())

    {

        delete curves.takeLast();

    }

    // remove all widgets

    while (plotWidgets.size())

    {

        delete plotWidgets.takeLast();

    }

    if (scrollArea != NULL) delete scrollArea;

}

void PlotManager::onChannelInfoChanged(const QModelIndex &topLeft,

                                       const QModelIndex &bottomRight,

                                       const QVector<int> &roles)

{

    int start = topLeft.row();

    int end = bottomRight.row();

    for (int ci = start; ci <= end; ci++)

    {

        QString name = topLeft.sibling(ci, ChannelInfoModel::COLUMN_NAME).data(Qt::EditRole).toString();

        QColor color = topLeft.sibling(ci, ChannelInfoModel::COLUMN_NAME).data(Qt::ForegroundRole).value<QColor>();

        bool visible = topLeft.sibling(ci, ChannelInfoModel::COLUMN_VISIBILITY).data(Qt::CheckStateRole).toBool();

        curves[ci]->setTitle(name);

        curves[ci]->setPen(color);

        curves[ci]->setVisible(visible);

        // replot only updated widgets

        if (isMulti)

        {

            plotWidgets[ci]->updateSymbols(); // required for color change

            plotWidgets[ci]->replot();

        }

    }

    // replot single widget

    if (!isMulti)

    {

        plotWidgets[0]->updateSymbols();

        replot();

    }

}

void PlotManager::setMulti(bool enabled)

{

    if (enabled == isMulti) return;

    isMulti = enabled;

    // detach all curves

    for (auto curve : curves)

    {

        curve->detach();

    }

    // remove all widgets

    while (plotWidgets.size())

    {

        delete plotWidgets.takeLast();

    }

    // setup new layout

    setupLayout(isMulti);

    if (isMulti)

    {

        // add new widgets and attach