curves[ci]->setItemAttribute(QwtPlotItem::Legend, visible);

        // replot only updated widgets

        if (isMulti)

        {

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

            plotWidgets[ci]->updateLegend(curves[ci]);

            plotWidgets[ci]->setVisible(visible);

            if (visible)

            {

                plotWidgets[ci]->replot();

            }

        }

    }

    checkNoVisChannels();

    // replot single widget

    if (!isMulti)

    {

        plotWidgets[0]->updateSymbols();

        plotWidgets[0]->updateLegend();

        replot();

    }

}

void PlotManager::checkNoVisChannels()

{

    // if all channels are hidden show indicator

    bool allhidden = std::none_of(curves.cbegin(), curves.cend(),

                                  [](QwtPlotCurve* c) {return c->isVisible();});

    plotWidgets[0]->showNoChannel(allhidden);

    if (isMulti)

    {

        plotWidgets[0]->showNoChannel(allhidden);

        plotWidgets[0]->setVisible(true);

    }

}

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

        for (auto curve : curves)

        {

            auto plot = addPlotWidget();

            plot->setVisible(curve->isVisible());

            curve->attach(plot);

        }

    }

    else

    {

        // add a single widget

        auto plot = addPlotWidget();

        // attach all curves

        for (auto curve : curves)

        {

            curve->attach(plot);

        }

    }

    checkNoVisChannels();

}

void PlotManager::showBarPlot(bool show)

{

    // A secondary plot can only be shown if splitter is provided.

    Q_ASSERT(_splitter != NULL);

    if (show)

    {

        Q_ASSERT(barPlot == NULL);

        barPlot = new BarPlot(_channelMan, _splitter);

    }

    else

    {

        Q_ASSERT(barPlot != NULL);

        delete barPlot;

        barPlot = NULL;

    }

}

void PlotManager::setupLayout(bool multiPlot)

{

    // delete previous layout if it exists

    if (_plotArea->layout() != 0)

    {

        delete _plotArea->layout();

    }

    if (multiPlot)

    {

        // setup a scroll area

        scrollArea = new QScrollArea();

        auto scrolledPlotArea = new QWidget(scrollArea);

        scrollArea->setWidget(scrolledPlotArea);

        scrollArea->setWidgetResizable(true);

        _plotArea->setLayout(new QVBoxLayout());

        _plotArea->layout()->addWidget(scrollArea);

        _plotArea->layout()->setContentsMargins(0,0,0,0);

        layout = new QVBoxLayout(scrolledPlotArea);

    }

    else

    {

        // delete scrollArea left from multi layout

        if (scrollArea != NULL)

        {

            delete scrollArea;

            scrollArea = NULL;

        }

        layout = new QVBoxLayout(_plotArea);

    }

    layout->setContentsMargins(2,2,2,2);

    layout->setSpacing(1);

}

Plot* PlotManager::addPlotWidget()

{

    auto plot = new Plot();

    plotWidgets.append(plot);

    layout->addWidget(plot);

    plot->darkBackground(darkBackgroundAction.isChecked());

    plot->showGrid(showGridAction.isChecked());

    plot->showMinorGrid(showMinorGridAction.isChecked());

    plot->showLegend(showLegendAction.isChecked());

    plot->showDemoIndicator(isDemoShown);

    plot->setYAxis(_autoScaled, _yMin, _yMax);

    plot->setNumOfSamples(_numOfSamples);

    plot->setSymbols(showSymbols);

    plot->setPlotWidth(_plotWidth);

    if (_xAxisAsIndex)

    {

        plot->setXAxis(0, _numOfSamples);

    }

    else

    {

        plot->setXAxis(_xMin, _xMax);

    }

    return plot;

}

void PlotManager::addCurve(QString title, FrameBuffer* buffer)

{

    auto curve = new QwtPlotCurve(title);

    auto series = new FrameBufferSeries(buffer);

    series->setXAxis(_xAxisAsIndex, _xMin, _xMax);

    curve->setSamples(series);

    _addCurve(curve);

}

void PlotManager::addCurve(QString title, QVector<QPointF> data)

{

    auto curve = new QwtPlotCurve(title);

    curve->setSamples(data);

    _addCurve(curve);

}

void PlotManager::_addCurve(QwtPlotCurve* curve)

{

    // store and init the curve

    curves.append(curve);