ChartDirector 6.1 (Java Edition)

Start Angle and Direction


  

This example demonstrates different sector layout angles and directions.

By default, ChartDirector positions sectors starting from the upward pointing position, and in clockwise direction.

The start angle and layout direction can be changed using PieChart.setStartAngle.

One common application for PieChart.setStartAngle is to facilitate layout of pie charts containing many small sectors. Please refer to Side Label Layout for an example.

Source Code Listing

[JSP Version] jspdemo/anglepie.jsp
<%@page import="ChartDirector.*" %>
<%@page import="javax.servlet.http.*" %>
<%!
// A simple structure to represent a chart image with an image map
private static class ImageWithHotSpot
{
    String imageURL;
    String imageMap;
}

// Function to create the demo charts
ImageWithHotSpot createChart(HttpServletRequest request, int chartIndex)
{
    // The data for the pie chart
    double[] data = {25, 18, 15, 12, 8, 30, 35};

    // The labels for the pie chart
    String[] labels = {"Labor", "Licenses", "Taxes", "Legal", "Insurance", "Facilities",
        "Production"};

    // Create a PieChart object of size 280 x 240 pixels
    PieChart c = new PieChart(280, 240);

    // Set the center of the pie at (140, 130) and the radius to 80 pixels
    c.setPieSize(140, 130, 80);

    // Add a title to the pie to show the start angle and direction
    if (chartIndex == 0) {
        c.addTitle("Start Angle = 0 degrees\nDirection = Clockwise");
    } else {
        c.addTitle("Start Angle = 90 degrees\nDirection = AntiClockwise");
        c.setStartAngle(90, false);
    }

    // Draw the pie in 3D
    c.set3D();

    // Set the pie data and the pie labels
    c.setData(data, labels);

    // Explode the 1st sector (index = 0)
    c.setExplode(0);

    // Output the chart
    ImageWithHotSpot ret = new ImageWithHotSpot();
    ret.imageURL = c.makeSession(request, "chart" + chartIndex);

    // Include tool tip for the chart
    ret.imageMap = c.getHTMLImageMap("", "", "title='{label}: US${value}K ({percent}%)'");

    return ret;
}
%>
<%
ImageWithHotSpot chart0 = createChart(request, 0);
ImageWithHotSpot chart1 = createChart(request, 1);
%>
<html>
<body style="margin:5px 0px 0px 5px">
<div style="font-size:18pt; font-family:verdana; font-weight:bold">
    Start Angle and Direction
</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?"+chart0.imageURL)%>'
    usemap="#map0" border="0">
<map name="map0"><%=chart0.imageMap%></map>
<img src='<%=response.encodeURL("getchart.jsp?"+chart1.imageURL)%>'
    usemap="#map1" border="0">
<map name="map1"><%=chart1.imageMap%></map>
</body>
</html>

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

public class anglepie implements DemoModule
{
    //Name of demo program
    public String toString() { return "Start Angle and Direction"; }

    //Number of charts produced in this demo
    public int getNoOfCharts() { return 2; }

    //Main code for creating charts
    public void createChart(ChartViewer viewer, int chartIndex)
    {
        // The data for the pie chart
        double[] data = {25, 18, 15, 12, 8, 30, 35};

        // The labels for the pie chart
        String[] labels = {"Labor", "Licenses", "Taxes", "Legal", "Insurance", "Facilities",
            "Production"};

        // Create a PieChart object of size 280 x 240 pixels
        PieChart c = new PieChart(280, 240);

        // Set the center of the pie at (140, 130) and the radius to 80 pixels
        c.setPieSize(140, 130, 80);

        // Add a title to the pie to show the start angle and direction
        if (chartIndex == 0) {
            c.addTitle("Start Angle = 0 degrees\nDirection = Clockwise");
        } else {
            c.addTitle("Start Angle = 90 degrees\nDirection = AntiClockwise");
            c.setStartAngle(90, false);
        }

        // Draw the pie in 3D
        c.set3D();

        // Set the pie data and the pie labels
        c.setData(data, labels);

        // Explode the 1st sector (index = 0)
        c.setExplode(0);

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

        //include tool tip for the chart
        viewer.setImageMap(c.getHTMLImageMap("clickable", "",
            "title='{label}: US${value}K ({percent}%)'"));
    }

    //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 anglepie();

        //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);
        frame.getContentPane().setLayout(new FlowLayout(FlowLayout.LEFT));
        frame.setSize(800, 450);

        // Create the charts and put them in the content pane
        for (int i = 0; i < demo.getNoOfCharts(); ++i)
        {
            ChartViewer viewer = new ChartViewer();
            demo.createChart(viewer, i);
            frame.getContentPane().add(viewer);
        }

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