ChartDirector Ver 5.0 (C++ Edition)

Stacked Bar Chart




This example demonstrates creating a stacked bar chart, completed with bar labels and legend box.

The key features demonstrated in this example are:

For bar labels, Layer.setDataLabelStyle and Layer.setAggregateLabelStyle control the styles (fonts, colors, backgrounds, etc), while Layer.setDataLabelFormat and Layer.setAggregateLabelFormat control the formats (the contents of the label, number of decimal points in numbers, etc). You may also add custom labels to the bars using Layer.addCustomDataLabel and Layer.addCustomAggregateLabel and Layer.addCustomGroupLabel.

Source Code Listing

[The following code is available in "cppdemo/stackedbar". 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"

int main(int argc, char *argv[])
{
    // The data for the bar chart
    double data0[] = {100, 125, 245, 147, 67};
    double data1[] = {85, 156, 179, 211, 123};
    double data2[] = {97, 87, 56, 267, 157};

    // The labels for the bar chart
    const char *labels[] = {"Mon", "Tue", "Wed", "Thu", "Fri"};

    // Create a XYChart object of size 500 x 320 pixels
    XYChart *c = new XYChart(500, 320);

    // Set the plotarea at (100, 40) and of size 280 x 240 pixels
    c->setPlotArea(100, 40, 280, 240);

    // Add a legend box at (400, 100)
    c->addLegend(400, 100);

    // Add a title to the chart using 14 points Times Bold Itatic font
    c->addTitle("Weekday Network Load", "timesbi.ttf", 14);

    // Add a title to the y axis. Draw the title upright (font angle = 0)
    c->yAxis()->setTitle("Average\nWorkload\n(MBytes\nPer Hour)")->setFontAngle(0);

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

    // Add a stacked bar layer and set the layer 3D depth to 8 pixels
    BarLayer *layer = c->addBarLayer(Chart::Stack, 8);

    // Add the three data sets to the bar layer
    layer->addDataSet(DoubleArray(data0, sizeof(data0)/sizeof(data0[0])), 0xff8080,
        "Server # 1");
    layer->addDataSet(DoubleArray(data1, sizeof(data1)/sizeof(data1[0])), 0x80ff80,
        "Server # 2");
    layer->addDataSet(DoubleArray(data2, sizeof(data2)/sizeof(data2[0])), 0x8080ff,
        "Server # 3");

    // Enable bar label for the whole bar
    layer->setAggregateLabelStyle();

    // Enable bar label for each segment of the stacked bar
    layer->setDataLabelStyle();

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

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