ChartDirector 6.1 (Java Edition)

Overlapping Bar Chart




This example demonstrates a multi-bar chart in which the bars within a cluster overlaps.

The overlapping effect is configured using BarLayer.setOverlapRatio. This method allows you to specify overlapping ratio and order. In this example, the overlapping ratio is 0.5, while the default overlapping order is used. The default order is that the first data set will stay on top of the second data set, and so on.

Source Code Listing

[JSP Version] jspdemo/overlapbar.jsp
<%@page import="ChartDirector.*" %>
<%
// The data for the bar chart
double[] data0 = {100, 125, 156, 147, 87, 124, 178, 109, 140, 106, 192, 122};
double[] data1 = {122, 156, 179, 211, 198, 177, 160, 220, 190, 188, 220, 270};
double[] data2 = {167, 190, 213, 267, 250, 320, 212, 199, 245, 267, 240, 310};
String[] labels = {"Jan", "Feb", "Mar", "Apr", "May", "Jun", "Jul", "Aug", "Sept", "Oct", "Nov",
    "Dec"};

// Create a XYChart object of size 580 x 280 pixels
XYChart c = new XYChart(580, 280);

// Add a title to the chart using 14pt Arial Bold Italic font
c.addTitle("Product Revenue For Last 3 Years", "Arial Bold Italic", 14);

// Set the plot area at (50, 50) and of size 500 x 200. Use two alternative background colors
// (f8f8f8 and ffffff)
c.setPlotArea(50, 50, 500, 200, 0xf8f8f8, 0xffffff);

// Add a legend box at (50, 25) using horizontal layout. Use 8pt Arial as font, with transparent
// background.
c.addLegend(50, 25, false, "Arial", 8).setBackground(Chart.Transparent);

// Set the x axis labels
c.xAxis().setLabels(labels);

// Draw the ticks between label positions (instead of at label positions)
c.xAxis().setTickOffset(0.5);

// Add a multi-bar layer with 3 data sets
BarLayer layer = c.addBarLayer2(Chart.Side);
layer.addDataSet(data0, 0xff8080, "Year 2003");
layer.addDataSet(data1, 0x80ff80, "Year 2004");
layer.addDataSet(data2, 0x8080ff, "Year 2005");

// Set 50% overlap between bars
layer.setOverlapRatio(0.5);

// Add a title to the y-axis
c.yAxis().setTitle("Revenue (USD in millions)");

// Output the chart
String chart1URL = c.makeSession(request, "chart1");

// Include tool tip for the chart
String imageMap1 = c.getHTMLImageMap("", "",
    "title='{xLabel} Revenue on {dataSetName}: {value} millions'");
%>
<html>
<body style="margin:5px 0px 0px 5px">
<div style="font-size:18pt; font-family:verdana; font-weight:bold">
    Overlapping Bar Chart
</div>
<hr color="#000080">
<div style="font-size:10pt; font-family:verdana; margin-bottom:1.5em">
    <a href="viewsource.jsp?file=<%=request.getServletPath()%>">View Source Code</a>
</div>
<img src='<%=response.encodeURL("getchart.jsp?"+chart1URL)%>'
    usemap="#map1" border="0">
<map name="map1"><%=imageMap1%></map>
</body>
</html>

[Java Version] javademo/overlapbar.java
import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
import ChartDirector.*;

public class overlapbar implements DemoModule
{
    //Name of demo program
    public String toString() { return "Overlapping Bar Chart"; }

    //Number of charts produced in this demo
    public int getNoOfCharts() { return 1; }

    //Main code for creating charts
    public void createChart(ChartViewer viewer, int chartIndex)
    {
        // The data for the bar chart
        double[] data0 = {100, 125, 156, 147, 87, 124, 178, 109, 140, 106, 192, 122};
        double[] data1 = {122, 156, 179, 211, 198, 177, 160, 220, 190, 188, 220, 270};
        double[] data2 = {167, 190, 213, 267, 250, 320, 212, 199, 245, 267, 240, 310};
        String[] labels = {"Jan", "Feb", "Mar", "Apr", "May", "Jun", "Jul", "Aug", "Sept", "Oct",
            "Nov", "Dec"};

        // Create a XYChart object of size 580 x 280 pixels
        XYChart c = new XYChart(580, 280);

        // Add a title to the chart using 14pt Arial Bold Italic font
        c.addTitle("Product Revenue For Last 3 Years", "Arial Bold Italic", 14);

        // Set the plot area at (50, 50) and of size 500 x 200. Use two alternative background
        // colors (f8f8f8 and ffffff)
        c.setPlotArea(50, 50, 500, 200, 0xf8f8f8, 0xffffff);

        // Add a legend box at (50, 25) using horizontal layout. Use 8pt Arial as font, with
        // transparent background.
        c.addLegend(50, 25, false, "Arial", 8).setBackground(Chart.Transparent);

        // Set the x axis labels
        c.xAxis().setLabels(labels);

        // Draw the ticks between label positions (instead of at label positions)
        c.xAxis().setTickOffset(0.5);

        // Add a multi-bar layer with 3 data sets
        BarLayer layer = c.addBarLayer2(Chart.Side);
        layer.addDataSet(data0, 0xff8080, "Year 2003");
        layer.addDataSet(data1, 0x80ff80, "Year 2004");
        layer.addDataSet(data2, 0x8080ff, "Year 2005");

        // Set 50% overlap between bars
        layer.setOverlapRatio(0.5);

        // Add a title to the y-axis
        c.yAxis().setTitle("Revenue (USD in millions)");

        // Output the chart
        viewer.setChart(c);

        //include tool tip for the chart
        viewer.setImageMap(c.getHTMLImageMap("clickable", "",
            "title='{xLabel} Revenue on {dataSetName}: {value} millions'"));
    }

    //Allow this module to run as standalone program for easy testing
    public static void main(String[] args)
    {
        //Instantiate an instance of this demo module
        DemoModule demo = new overlapbar();

        //Create and set up the main window
        JFrame frame = new JFrame(demo.toString());
        frame.addWindowListener(new WindowAdapter() {
            public void windowClosing(WindowEvent e) {System.exit(0);} });
        frame.getContentPane().setBackground(Color.white);

        // Create the chart and put them in the content pane
        ChartViewer viewer = new ChartViewer();
        demo.createChart(viewer, 0);
        frame.getContentPane().add(viewer);

        // Display the window
        frame.pack();
        frame.setVisible(true);
    }
}