ChartDirector 7.1 (C++ Edition)

Gradient Multi-Bar Chart




This example demonstrates a multi-bar chart with bar gradient shading and gradient color for plot area background.

Source Code Listing

The following is the command line version of the code in "cppdemo/gradientmultibar". The MFC version of the code is in "mfcdemo/mfcdemo". The Qt Widgets version of the code is in "qtdemo/qtdemo". The QML/Qt Quick version of the code is in "qmldemo/qmldemo".
#include "chartdir.h" int main(int argc, char *argv[]) { // The data for the bar chart double data0[] = {100, 125, 245, 147, 67}; const int data0_size = (int)(sizeof(data0)/sizeof(*data0)); double data1[] = {85, 156, 179, 211, 123}; const int data1_size = (int)(sizeof(data1)/sizeof(*data1)); double data2[] = {97, 87, 56, 267, 157}; const int data2_size = (int)(sizeof(data2)/sizeof(*data2)); const char* labels[] = {"Mon", "Tue", "Wed", "Thur", "Fri"}; const int labels_size = (int)(sizeof(labels)/sizeof(*labels)); // Create a XYChart object of size 540 x 375 pixels XYChart* c = new XYChart(540, 375); // Add a title to the chart using 18pt Times Bold Italic font c->addTitle("Average Weekly Network Load", "Times New Roman Bold Italic", 18); // Set the plotarea at (50, 55) and of 440 x 280 pixels in size. Use a vertical gradient color // from grey (888888) to black (000000) as background. Set border and grid lines to white // (ffffff). c->setPlotArea(50, 55, 440, 280, c->linearGradientColor(0, 55, 0, 335, 0x888888, 0x000000), -1, 0xffffff, 0xffffff); // Add a legend box at (50, 25) using horizontal layout. Use 10pt Arial Bold as font, with // transparent background. c->addLegend(50, 25, false, "Arial Bold", 10)->setBackground(Chart::Transparent); // Set the x axis labels c->xAxis()->setLabels(StringArray(labels, labels_size)); // Draw the ticks between label positions (instead of at label positions) c->xAxis()->setTickOffset(0.5); // Set axis label style to 8pt Arial Bold c->xAxis()->setLabelStyle("Arial Bold", 8); c->yAxis()->setLabelStyle("Arial Bold", 8); // Set axis line width to 2 pixels c->xAxis()->setWidth(2); c->yAxis()->setWidth(2); // Add axis title c->yAxis()->setTitle("Throughput (MBytes Per Hour)"); // Add a multi-bar layer with 3 data sets and 4 pixels 3D depth BarLayer* layer = c->addBarLayer(Chart::Side, 4); layer->addDataSet(DoubleArray(data0, data0_size), 0x66aaee, "Server #1"); layer->addDataSet(DoubleArray(data1, data1_size), 0xeebb22, "Server #2"); layer->addDataSet(DoubleArray(data2, data2_size), 0xcc0000, "Server #3"); // Set bar border to transparent. Use bar gradient lighting with light intensity from 0.75 to // 1.75. layer->setBorderColor(Chart::Transparent, Chart::barLighting(0.75, 1.75)); // Configure the bars within a group to touch each others (no gap) layer->setBarGap(0.2, Chart::TouchBar); // Output the chart c->makeChart("gradientmultibar.png"); //free up resources delete c; return 0; }