ChartDirector 6.0 (C++ Edition)

Symbol Line Chart




This example demonstrates using symbols to represent data points, and putting data labels on top of the symbols.

Note that in this example, the chart title background is not a solid color but a 1 x 2 pixels pattern.

Source Code Listing

[The following code is available in "cppdemo/symbolline". 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 line chart
    double data0[] = {60.2, 51.7, 81.3, 48.6, 56.2, 68.9, 52.8};
    double data1[] = {30.0, 32.7, 33.9, 29.5, 32.2, 28.4, 29.8};
    const char *labels[] = {"Sun", "Mon", "Tue", "Wed", "Thu", "Fri", "Sat"};

    // Create a XYChart object of size 300 x 180 pixels, with a pale yellow (0xffffc0) background, a
    // black border, and 1 pixel 3D border effect.
    XYChart *c = new XYChart(300, 180, 0xffffc0, 0x000000, 1);

    // Set the plotarea at (45, 35) and of size 240 x 120 pixels, with white background. Turn on
    // both horizontal and vertical grid lines with light grey color (0xc0c0c0)
    c->setPlotArea(45, 35, 240, 120, 0xffffff, -1, -1, 0xc0c0c0, -1);

    // Add a legend box at (45, 12) (top of the chart) using horizontal layout and 8pt Arial font
    // Set the background and border color to Transparent.
    c->addLegend(45, 12, false, "", 8)->setBackground(Chart::Transparent);

    // Add a title to the chart using 9pt Arial Bold/white font. Use a 1 x 2 bitmap pattern as the
    // background.
    int pattern1[] = {0x004000, 0x008000};
    c->addTitle("Server Load (Jun 01 - Jun 07)", "arialbd.ttf", 9, 0xffffff)->setBackground(
        c->patternColor(IntArray(pattern1, (int)(sizeof(pattern1) / sizeof(pattern1[0]))), 2));

    // Set the y axis label format to nn%
    c->yAxis()->setLabelFormat("{value}%");

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

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

    // Add the first line. Plot the points with a 7 pixel square symbol
    layer->addDataSet(DoubleArray(data0, (int)(sizeof(data0) / sizeof(data0[0]))), 0xcf4040, "Peak"
        )->setDataSymbol(Chart::SquareSymbol, 7);

    // Add the second line. Plot the points with a 9 pixel dismond symbol
    layer->addDataSet(DoubleArray(data1, (int)(sizeof(data1) / sizeof(data1[0]))), 0x40cf40,
        "Average")->setDataSymbol(Chart::DiamondSymbol, 9);

    // Enable data label on the data points. Set the label format to nn%.
    layer->setDataLabelFormat("{value|0}%");

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

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