ChartDirector Ver 4.1 (ColdFusion Edition)

Circular Label Layout


  

This example demonstrates various options in the "circular label layout" method. It also demonstrates the use of alternative sector label format.

By default, in "circular label layout", the sector labels will be external and close to the perimeter of the pie.

The PieChart.setLabelPos method can be used to control the distance between the sector labels and the perimeter. It also allows enabling join lines to connect the labels to the sectors, which are useful if the labels are far away from the perimeter.

The distance between the sector labels and the perimeter can be negative, in which case the sectors will be internal to the pie.

Note also the sector label format in this example, which consists of 3 lines. It is specified using PieChart.setLabelFormat.

Source Code Listing

[File: cfdemo/circlelabelpie.cfm]
<cfscript>

// ChartDirector for ColdFusion API Access Point
cd = CreateObject("java", "ChartDirector.CFChart");

// A utility to allow us to create arrays with data in one line of code
function Array() {
    var result = ArrayNew(1);
    var i = 0;
    for (i = 1; i LTE ArrayLen(arguments); i = i + 1)
        result[i] = arguments[i];
    return result;
}

// Function to create the demo charts
function createChart(img)
{
    // Declare local variables
    var data = 0;
    var labels = 0;
    var c = 0;
    var ret = 0;

    // The data for the pie chart
    data = Array(25, 18, 15, 12, 30, 35);

    // The labels for the pie chart
    labels = Array("Labor", "Licenses", "Taxes", "Legal", "Facilities", "Production")
        ;

    // Create a PieChart object of size 300 x 300 pixels
    c = cd.PieChart(300, 300);

    if (img EQ "0") {
    //============================================================
    //    Draw a pie chart where the label is on top of the pie
    //============================================================

        // Set the center of the pie at (150, 150) and the radius to 120 pixels
        c.setPieSize(150, 150, 120);

        // Set the label position to -40 pixels from the perimeter of the pie (-ve
        // means label is inside the pie)
        c.setLabelPos(-40);

    } else {
    //============================================================
    //    Draw a pie chart where the label is outside the pie
    //============================================================

        // Set the center of the pie at (150, 150) and the radius to 80 pixels
        c.setPieSize(150, 150, 80);

        // Set the sector label position to be 20 pixels from the pie. Use a join
        // line to connect the labels to the sectors.
        c.setLabelPos(20, cd.LineColor);

    }

    // Set the label format to three lines, showing the sector name, value, and
    // percentage. The value 999 will be formatted as US$999K.
    c.setLabelFormat("{label}<*br*>US${value}K<*br*>({percent}%)");

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

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

    // Output the chart
    ret = StructNew();
    ret.imageURL = c.makeSession(GetPageContext(), "chart" & img);

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

    return ret;
}

chart0 = createChart(0);
chart1 = createChart(1);

</cfscript>
<html>
<body style="margin:5px 0px 0px 5px">
<div style="font-size:18pt; font-family:verdana; font-weight:bold">
    Circular Label Layout
</div>
<hr style="border:solid 1px #000080" />
<cfoutput>
<div style="font-size:9pt; font-family:verdana; margin-bottom:1.5em">
    <a href='viewsource.cfm?file=#CGI.SCRIPT_NAME#'>View Source Code</a>
</div>
<img src="getchart.cfm?#chart0.imageURL#" usemap="##map0" border="0" />
<map name="map0">#chart0.imageMap#</map>
<img src="getchart.cfm?#chart1.imageURL#" usemap="##map1" border="0" />
<map name="map1">#chart1.imageMap#</map>
</cfoutput>
</body>
</html>