ChartDirector 7.0 (C++ Edition)

Custom Symbols




This example demonstrates loading external image files as data symbols by using DataSet.setDataSymbol2.

Source Code Listing

[The following code is available in "cppdemo/customsymbolline". 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 chart
    double data0[] = {600, 800, 1200, 1500, 1800, 1900, 2000, 1950};
    const int data0_size = (int)(sizeof(data0)/sizeof(*data0));
    double data1[] = {300, 450, 500, 1000, 1500, 1600, 1650, 1600};
    const int data1_size = (int)(sizeof(data1)/sizeof(*data1));

    // The labels for the chart
    const char* labels[] = {"1995", "1996", "1997", "1998", "1999", "2000", "2001", "2002"};
    const int labels_size = (int)(sizeof(labels)/sizeof(*labels));

    // Create a XYChart object of size 450 x 250 pixels, with a pale yellow (0xffffc0) background, a
    // black border, and 1 pixel 3D border effect.
    XYChart* c = new XYChart(450, 250, 0xffffc0, 0, 1);

    // Set the plotarea at (60, 45) and of size 360 x 170 pixels, using white (0xffffff) as the plot
    // area background color. Turn on both horizontal and vertical grid lines with light grey color
    // (0xc0c0c0)
    c->setPlotArea(60, 45, 360, 170, 0xffffff, -1, -1, 0xc0c0c0, -1);

    // Add a legend box at (60, 20) (top of the chart) with horizontal layout. Use 8pt Arial Bold
    // font. Set the background and border color to Transparent.
    c->addLegend(60, 20, false, "arialbd.ttf", 8)->setBackground(Chart::Transparent);

    // Add a title to the chart using 12pt Arial Bold/white font with a dark blue (000060)
    // background.
    c->addTitle("Information Resource Usage", "arialbd.ttf", 12, 0xffffff)->setBackground(0x000060);

    // Set the labels on the x axis
    c->xAxis()->setLabels(StringArray(labels, labels_size));

    // Reserve 8 pixels margins at both side of the x axis to avoid the first and last symbols
    // drawing outside of the plot area
    c->xAxis()->setMargin(8, 8);

    // Add a title to the y axis
    c->yAxis()->setTitle("Population");

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

    // Add the first line using small_user.png as the symbol.
    layer->addDataSet(DoubleArray(data0, data0_size), 0xcf4040, "Users")->setDataSymbol(
        "small_user.png");

    // Add the first line using small_computer.png as the symbol.
    layer->addDataSet(DoubleArray(data1, data1_size), 0x40cf40, "Computers")->setDataSymbol(
        "small_computer.png");

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

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

    //free up resources
    delete c;

    return 0;
}