Class ChartWidget

examples/Grids/CartesianGrid/main.cpp:27–174

using namespace KDChart;

class ChartWidget : public QWidget
{
    Q_OBJECT
public:
    explicit ChartWidget(QWidget *parent = nullptr)
        : QWidget(parent)
    {
        m_model.insertRows(0, 6, QModelIndex());
        m_model.insertColumns(0, 4, QModelIndex());
        for (int row = 0; row < 6; ++row) {
            for (int column = 0; column < 4; ++column) {
                QModelIndex index = m_model.index(row, column, QModelIndex());
                m_model.setData(index, QVariant(row * 0.5 + column));
            }
        }

        auto *diagram = new LineDiagram;
        diagram->setModel(&m_model);

        auto *xAxis = new CartesianAxis(diagram);
        auto *yAxis = new CartesianAxis(diagram);
        xAxis->setPosition(KDChart::CartesianAxis::Bottom);
        yAxis->setPosition(KDChart::CartesianAxis::Left);
        diagram->addAxis(xAxis);
        diagram->addAxis(yAxis);

        m_chart.coordinatePlane()->replaceDiagram(diagram);

        /* Header */

        // Add at one Header and set it up
        auto *header = new HeaderFooter(&m_chart);
        header->setPosition(Position::North);
        header->setText("A Line Chart with Grid Configured");
        m_chart.addHeaderFooter(header);

        // Configure the Header text attributes
        TextAttributes hta;
        hta.setPen(QPen(Qt::red));

        // let the header resize itself
        // together with the widget.
        // so-called relative size
        Measure m(35.0);
        m.setRelativeMode(header->autoReferenceArea(),
                          KDChartEnums::MeasureOrientationMinimum);
        hta.setFontSize(m);
        // min font size
        m.setValue(3.0);
        m.setCalculationMode(KDChartEnums::MeasureCalculationModeAbsolute);
        hta.setMinimalFontSize(m);
        header->setTextAttributes(hta);

        // Configure the Header's Background
        BackgroundAttributes hba;
        hba.setBrush(Qt::white);
        hba.setVisible(true);
        header->setBackgroundAttributes(hba);