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RGraph is a JavaScript charts library based on HTML5 SVG and canvas. RGraph is mature (over 15 years old) and has a wealth of features making it an ideal choice to show charts on your website.

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A Segmented Donut chart

[No canvas support]

The Segmented donut chart was formerly a variation of the Pie chart, however now it has been promoted to a standalone chart type. It represents a single value as a proportion of the whole - a circular progress bar effectively.

The chart is quite small and fits well on smaller devices so it doesn't need a lot of changing with the responsive function. Only the width and labelSize properties are adjusted and the css float value is changed.

An event listener is added to the canvas (using the standard addEventListener function) so that when you click on the chart the value of where you click is retrieved (using the objects getValue function, set on the chart object and then the chart animates to the new value.

This goes in the documents header:
<script src="RGraph.common.core.js"></script>
<script src="RGraph.segmented.js"></script>
Put this where you want the chart to show up:
<div>
    <canvas id="cvs" width="350" height="350">[No canvas support]</canvas>
</div>
This is the code that generates the chart - it should be placed AFTER the canvas tag(s):
<script>
    segmented = new RGraph.Segmented({
        id: 'cvs',
        max: 100,
        value: 70,
        options: {
            labelsCenterUnitsPost: '%',
            labelsCenterColor: '#aaa',
            responsive: [
                {maxWidth: null,width: 350,height: 350,options:{width: 55,labelsCenterSize: 60},parentCss:{'float':'right', textAlign:'none'}},
                {maxWidth: 700,width: 250,height: 250,options:{width: 40,labelsCenterSize: 45},parentCss:{'float':'none', textAlign:'center'}}
            ]
        }
    }).roundRobin({frames: 60});



    //
    // If the chart is clicked then adjust the value
    //
    segmented.canvas.addEventListener('click', function (e)
    {
        var value = segmented.getValue(e);
        
        if (value) {
            segmented.value = value;
            segmented.grow();
        }
    }, false);
</script>