ChartDirector 6.0 (C++ Edition)

Data Table (1)




This example demonstrates putting a data table under the x-axis.

In ChartDirector, the labels in a label based x-axis (that is, axis configured with Axis.setLabels or Axis.setLabels2) can be converted to a table using Axis.makeLabelTable.

Note: Axis.makeLabelTable is only supported on a label based axis with no label stepping. You should not use this method with other axis configuration.


The Axis.makeLabelTable returns a CDMLTable object representing the table. It can be used to add more content to the table and to configure the appearance of the table.

In this example, 3 rows with alternating background colors are added to the table using CDMLTable.appendRow. The cells in the rows are filled with data values using CDMLTable.setText. A column is added to the left of the table using CDMLTable.insertCol, and filled with the legend icons obtained using Layer.getLegendIcon.

Source Code Listing

[The following code is available in "cppdemo/datatable". A MFC version of the code is available in "mfcdemo/mfcdemo" (Windows edition only). A QT version of the code is available in "qtdemo/qtdemo".]
#include "chartdir.h"
#include <stdio.h>

int main(int argc, char *argv[])
{
    char buffer[256];

    // The data for the line chart
    double data0[] = {42, 49, 33, 38, 64, 56, 29, 41, 44, 57, 59, 42};
    double data1[] = {65, 75, 47, 34, 42, 49, 73, 62, 90, 69, 66, 78};
    double data2[] = {36, 28, 25, 28, 38, 20, 22, 30, 25, 33, 30, 24};
    const char *labels[] = {"Jan", "Feb", "Mar", "Apr", "May", "Jun", "Jul", "Aug", "Sep", "Oct",
        "Nov", "Dec"};

    // Create a XYChart object of size 600 x 400 pixels
    XYChart *c = new XYChart(600, 400);

    // Add a title to the chart using 18pt Times Bold Italic font
    TextBox *title = c->addTitle("Product Line Global Revenue", "timesbi.ttf", 18);

    // Tentatively set the plotarea at (50, 55) and of (chart_width - 100) x (chart_height - 120)
    // pixels in size. Use a vertical gradient color from sky blue (aaccff) t0 light blue (f9f9ff)
    // as background. Set both horizontal and vertical grid lines to dotted semi-transprent black
    // (aa000000).
    PlotArea *plotArea = c->setPlotArea(50, 55, c->getWidth() - 100, c->getHeight() - 120,
        c->linearGradientColor(0, 55, 0, 55 + c->getHeight() - 120, 0xaaccff, 0xf9fcff), -1, -1,
        c->dashLineColor(0xaa000000, Chart::DotLine), -1);

    // Add a legend box and anchored the top center at the horizontal center of the chart, just
    // under the title. Use 10pt Arial Bold as font, with transparent background and border.
    LegendBox *legendBox = c->addLegend(c->getWidth() / 2, title->getHeight(), false, "arialbd.ttf",
        10);
    legendBox->setAlignment(Chart::TopCenter);
    legendBox->setBackground(Chart::Transparent, Chart::Transparent);

    // Set y-axis title using 10 points Arial Bold Italic font, label style to 8 points Arial Bold,
    // and axis color to transparent
    c->yAxis()->setTitle("Revenue (USD millions)", "arialbi.ttf", 10);
    c->yAxis()->setLabelStyle("arialbd.ttf", 8);
    c->yAxis()->setColors(Chart::Transparent);

    // Set y-axis tick density to 30 pixels. ChartDirector auto-scaling will use this as the
    // guideline when putting ticks on the y-axis.
    c->yAxis()->setTickDensity(30);

    // Add a line layer to the chart
    LineLayer *layer = c->addLineLayer();

    // Set the line width to 3 pixels
    layer->setLineWidth(3);

    // Add the three data sets to the line layer, using circles, diamands and X shapes as symbols
    layer->addDataSet(DoubleArray(data0, (int)(sizeof(data0) / sizeof(data0[0]))), 0xff0000,
        "Quantum Computer")->setDataSymbol(Chart::CircleSymbol, 9);
    layer->addDataSet(DoubleArray(data1, (int)(sizeof(data1) / sizeof(data1[0]))), 0x00ff00,
        "Atom Synthesizer")->setDataSymbol(Chart::DiamondSymbol, 11);
    layer->addDataSet(DoubleArray(data2, (int)(sizeof(data2) / sizeof(data2[0]))), 0xff6600,
        "Proton Cannon")->setDataSymbol(Chart::Cross2Shape(), 11);

    // Set the x axis labels
    c->xAxis()->setLabels(StringArray(labels, (int)(sizeof(labels) / sizeof(labels[0]))));

    // Convert the labels on the x-axis to a CDMLTable
    CDMLTable *table = c->xAxis()->makeLabelTable();

    // Set the default top/bottom margins of the cells to 3 pixels
    table->getStyle()->setMargin(0, 0, 3, 3);

    // Use Arial Bold as the font for the first row
    table->getRowStyle(0)->setFontStyle("arialbd.ttf");

    //
    // We can add more information to the table. In this sample code, we add the data series and the
    // legend icons to the table.
    //

    // Add 3 more rows to the table. Set the background of the 1st and 3rd rows to light grey
    // (eeeeee).
    table->appendRow()->setBackground(0xeeeeee, Chart::LineColor);
    table->appendRow();
    table->appendRow()->setBackground(0xeeeeee, Chart::LineColor);

    // Put the values of the 3 data series to the cells in the 3 rows
    for(int i = 0; i < (int)(sizeof(data0) / sizeof(data0[0])); ++i) {
        sprintf(buffer, "%g", data0[i]);
        table->setText(i, 1, buffer);
        sprintf(buffer, "%g", data1[i]);
        table->setText(i, 2, buffer);
        sprintf(buffer, "%g", data2[i]);
        table->setText(i, 3, buffer);
    }

    // Insert a column on the left for the legend icons. Use 5 pixels left/right margins and 3
    // pixels top/bottom margins for the cells in this column.
    table->insertCol(0)->setMargin(5, 5, 3, 3);

    // The top cell is set to transparent, so it is invisible
    table->getCell(0, 0)->setBackground(Chart::Transparent, Chart::Transparent);

    // The other 3 cells are set to the legend icons of the 3 data series
    table->setText(0, 1, layer->getLegendIcon(0));
    table->setText(0, 2, layer->getLegendIcon(1));
    table->setText(0, 3, layer->getLegendIcon(2));

    // Layout legend box first, so we can get its size
    c->layoutLegend();

    // Adjust the plot area size, such that the bounding box (inclusive of axes) is 2 pixels from
    // the left, right and bottom edge, and is just under the legend box.
    c->packPlotArea(2, legendBox->getTopY() + legendBox->getHeight(), c->getWidth() - 3,
        c->getHeight() - 3);

    // After determining the exact plot area position, we may adjust the legend box and the title
    // positions so that they are centered relative to the plot area (instead of the chart)
    legendBox->setPos(plotArea->getLeftX() + (plotArea->getWidth() - legendBox->getWidth()) / 2,
        legendBox->getTopY());
    title->setPos(plotArea->getLeftX() + (plotArea->getWidth() - title->getWidth()) / 2,
        title->getTopY());

    // Output the chart
    c->makeChart("datatable.png");

    //free up resources
    delete c;
    return 0;
}