ChartDirector 6.0 (C++ Edition)

Dual Horizontal Bar Charts




This example demonstrates combining two horizontal bar charts of opposite direction using a MultiChart, and a number of other ChartDirector features.

Source Code Listing

[The following code is available in "cppdemo/dualhbar". 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 age groups
    const char *labels[] = {"0 - 4", "5 - 9", "10 - 14", "15 - 19", "20 - 24", "24 - 29", "30 - 34",
        "35 - 39", "40 - 44", "44 - 49", "50 - 54", "55 - 59", "60 - 64", "65 - 69", "70 - 74",
        "75 - 79", "80+"};

    // The male population (in thousands)
    double male[] = {215, 238, 225, 236, 235, 260, 286, 340, 363, 305, 259, 164, 135, 127, 102, 68,
        66};

    // The female population (in thousands)
    double female[] = {194, 203, 201, 220, 228, 271, 339, 401, 384, 304, 236, 137, 116, 122, 112,
        85, 110};


    //=============================================================
    //    Draw the right bar chart
    //=============================================================

    // Create a XYChart object of size 320 x 300 pixels
    XYChart *c = new XYChart(320, 300);

    // Set the plotarea at (50, 0) and of size 250 x 255 pixels. Use pink (0xffdddd) as the
    // background.
    c->setPlotArea(50, 0, 250, 255, 0xffdddd);

    // Add a custom text label at the top right corner of the right bar chart
    c->addText(300, 0, "Female", "timesbi.ttf", 12, 0xa07070)->setAlignment(Chart::TopRight);

    // Add the pink (0xf0c0c0) bar chart layer using the female data
    BarLayer *femaleLayer = c->addBarLayer(DoubleArray(female, (int)(sizeof(female) / sizeof(female[
        0]))), 0xf0c0c0);

    // Swap the axis so that the bars are drawn horizontally
    c->swapXY(true);

    // Set the bar to touch each others
    femaleLayer->setBarGap(Chart::TouchBar);

    // Set the border style of the bars to 1 pixel 3D border
    femaleLayer->setBorderColor(-1, 1);

    // Add a Transparent line layer to the chart using the male data. As it is Transparent, only the
    // female bar chart can be seen. We need to put both male and female data in both left and right
    // charts, because we want auto-scaling to produce the same scale for both chart.
    c->addLineLayer(DoubleArray(male, (int)(sizeof(male) / sizeof(male[0]))), Chart::Transparent);

    // Set the y axis label font to Arial Bold
    c->yAxis()->setLabelStyle("arialbd.ttf");

    // Set the labels between the two bar charts, which can be considered as the x-axis labels for
    // the right chart
    TextBox *tb = c->xAxis()->setLabels(StringArray(labels, (int)(sizeof(labels) / sizeof(labels[0])
        )));

    // Use a fix width of 50 for the labels (height = automatic) with center alignment
    tb->setSize(50, 0);
    tb->setAlignment(Chart::Center);

    // Set the label font to Arial Bold
    tb->setFontStyle("arialbd.ttf");

    // Disable ticks on the x-axis by setting the tick length to 0
    c->xAxis()->setTickLength(0);

    //=============================================================
    //    Draw the left bar chart
    //=============================================================

    // Create a XYChart object of size 280 x 300 pixels with a transparent background.
    XYChart *c2 = new XYChart(280, 300, Chart::Transparent);

    // Set the plotarea at (20, 0) and of size 250 x 255 pixels. Use pale blue (0xddddff) as the
    // background.
    c2->setPlotArea(20, 0, 250, 255, 0xddddff);

    // Add a custom text label at the top left corner of the left bar chart
    c2->addText(20, 0, "Male", "timesbi.ttf", 12, 0x7070a0);

    // Add the pale blue (0xaaaaff) bar chart layer using the male data
    BarLayer *maleLayer = c2->addBarLayer(DoubleArray(male, (int)(sizeof(male) / sizeof(male[0]))),
        0xaaaaff);

    // Swap the axis so that the bars are drawn horizontally
    c2->swapXY(true);

    // Reverse the direction of the y-axis so it runs from right to left
    c2->yAxis()->setReverse();

    // Set the bar to touch each others
    maleLayer->setBarGap(Chart::TouchBar);

    // Set the border style of the bars to 1 pixel 3D border
    maleLayer->setBorderColor(-1, 1);

    // Add a Transparent line layer to the chart using the female data. As it is Transparent, only
    // the male bar chart can be seen. We need to put both male and female data in both left and
    // right charts, because we want auto-scaling to produce the same scale for both chart.
    c2->addLineLayer(DoubleArray(female, (int)(sizeof(female) / sizeof(female[0]))),
        Chart::Transparent);

    // Set the y axis label font to Arial Bold
    c2->yAxis()->setLabelStyle("arialbd.ttf");

    //=============================================================
    //    Use a MultiChart to contain both bar charts
    //=============================================================

    // Create a MultiChart object of size 590 x 320 pixels.
    MultiChart *m = new MultiChart(590, 320);

    // Add a title to the chart using Arial Bold Italic font
    m->addTitle("Demographics Hong Kong Year 2002", "arialbi.ttf");

    // Add another title at the bottom using Arial Bold Italic font
    m->addTitle(Chart::Bottom, "Population (in thousands)", "arialbi.ttf", 10);

    // Put the right chart at (270, 25)
    m->addChart(270, 25, c);

    // Put the left chart at (0, 25)
    m->addChart(0, 25, c2);

    // Output the chart
    m->makeChart("dualhbar.png");

    //free up resources
    delete c;
    delete c2;
    delete m;
    return 0;
}