Pie charts documentation

 

Example

<script>
    var data = [564,155,499,611,322];

    var pie = new RGraph.Pie({
        id: 'cvs',
        data: data,
        options: {
            labels: ['Abc', 'Def', 'Ghi', 'Jkl', 'Mno'],
            linewidth: 2,
            strokestyle: 'white'
        }
    }).draw();
</script>

The example file is here.

 

Properties

You can use these properties to control how the pie chart looks. You can set them by using the Set() method. Eg:

myPie.set('name', 'value');

Layout style:     
  

Chart configuration

PropertyDescriptionDefault
centerxIf required, you can position the Pie chart using this instead of the gutters.null
centeryIf required, you can position the Pie chart using this instead of the gutters.null
radiusIf required, you can size the Pie chart using this instead of the gutters.null

Margins

PropertyDescriptionDefault
gutterLeftThe left gutter of the chart, (the gutter is where the labels and title are)).25
gutterRightThe right gutter of the chart, (the gutter is where the labels and title are).25
gutterTopThe top gutter of the chart, (the gutter is where the labels and title are).25
gutterBottomThe bottom gutter of the chart, (the gutter is where the labels and title are).25

Colors

PropertyDescriptionDefault
colorsColors to be used for the pie segments.['rgb(255,0,0)', '#ddd', 'rgb(0,255,0)', 'rgb(0,0,255)', 'rgb(255,255,0)', 'rgb(0,255,255)', 'red', 'pink', 'black', 'white']
strokestyleThe color of the seperating lines. This can also be an array of different colors - eg pie.set('strokestyle', ['red', 'blue', 'green'])#999

Labels and text

PropertyDescriptionDefault
textAccessibleA new feature in 2016 that allows you to use DOM text in place of canvas text. It makes for much higher quality text that you can also select if desired (for copy/paste operations). It won't fit all situations and you can read more about the DOM text feature here. A good way to control borders/margins/padding etc is not to set them on the canvas but to wrap the canvas in a div and set them on that like this:
<div style="margin-left: 50px; display: inline-block">
<canvas id="cvs" width="650" height="250"></canvas>
</div>
true
textAccessibleOverflowThis can be visible or hidden and it controls whether the text is clipped to the edges of the canvas. It defaults to be visible and means you can set small gutters if you wish.visible
textAccessiblePointereventsThis controls whether the DOM text responds to mouse based events or not (it sets the pointer-events CSS property to none).true
textSizeThe size of the text.10
textFontThe font used to render the text.Arial
textColorThe color of the labels.black
labelsAn array of labels to be used for the chart.An empty array
labelsColorsAn array of colors to be used for the labels.null
labelsBoldWhether the labels are bolded or not. An example is herefalse
labelsSticksStipulates that sticks for the labels are shown. This can also be an array of stick lengths - which may be useful if you're experiencing the labels clashing.false
labelsSticksColorsSets the color of the label sticks.#aaa
labelsSticksUsecolorsIf true this will set the sticks to use the same colors as the pie chart itselffalse
labelsSticksLengthSets the length of the label sticks.7
labelsSticksLinewidthSets the linewidth of the label sticks.1
labelsSticksListA new way of organising the labels - this should help avoid label text overlaps.false
labelsIngraphThis shows in-graph labels in each segmentnull
labelsIngraphBoundingWhether the in-graph labels are surrounded by a bounding boxtrue
labelsIngraphBoundingFillThe fill color of the bounding squarewhite
labelsIngraphUnitsPreThis string is PREPENDED to the label(empty string)
labelsIngraphUnitsPostThis string is APPENDED to th label(empty string)
labelsIngraphRadiusIf specified this is the radius that the labels are positioned at. If its a number between 0 and 2 it is MULTIPLIED with the radius to get the position. If its above 2 though its used as the EXACT radiusnull
labelsIngraphColorThe color of the labels.null
labelsIngraphFontThe font to use for the ingraph labelsSame as text.font
labelsIngraphSizeThe size of the ingraph labelsSame as text.size
labelsIngraphSpecificInstead of the values you use this option to specify the text that is shownnull
labelsCenterIf you have a donut chart this can show a label in the centernull
labelsCenterSizeThe size of the center label26
labelsCenterFontThe font used to render the labelArial
labelsCenterColorThe color of the center labelblack
labelsCenterItalicWhether the center label is italicfalse
labelsCenterBoldWhether the center label is boldfalse
labelsCenterUnitsPreThis string is PREPENDED to the labelnone
labelsCenterUnitsPostThis string is APPENDED to the labelnone

Titles

PropertyDescriptionDefault
titleThe title of the pie chart.none
titleFontThe font that the title is rendered in. If not specified the text.font setting is used (usually Arial)null
titleSizeThe size of the title. If not specified the size is usually 2pt bigger than the text.size setting.null
titleBoldWhather the title is bold or not.true
titleItalicWhether the title is italic or not.false
titleBackgroundThe background color (if any) for the title.null
titleColorThe color of the title.black
titleXTo give the exact X coordinate for the title - use thisnull
titleYTo give the exact Y coordinate for the title - use thisnull

Shadow

PropertyDescriptionDefault
shadowWhether a drop shadow is applied.true
shadowColorThe color of the shadow.#aaaa
shadowOffsetxThe X offset of the shadow.0
shadowOffsetyThe Y offset of the shadow.0
shadowBlurThe severity of the shadow blurring effect.15

Interactive features

PropertyDescriptionDefault
tooltipsA numerically indexed array of tooltips that are shown when a bar is clicked. These can contain HTML.[]
tooltipsEventThis is the event that triggers the tooltips. It can be either onclick or onmousemove.onclick
tooltipsEffectThe effect used for showing tooltips. Can be either fade or none.fade
tooltipsCssClassThis is the name of the CSS class the chart uses.RGraph_tooltip
tooltipsOverrideIf you wish to handle showing tooltips yourself, this should be a function object which does just that. There's more information on the tooltips documentation pagenull
tooltipsNohideonclearNot an option that you'll need particularly often if at all. Setting this to true means that when you call the RGraph.clear() API function tooltip DO NOT get hidden.false
contextmenuAn array of context menu items. More information on context menus is here.[] (An empty array)
annotatableWhether annotations are enabled for the chart (ie you can draw on the chart interactively.false
annotateColorIf you do not allow the use of the palette, then this will be the only colour allowed for annotations.black
annotateLinewidthThis is the line width of the annotations.1
resizableDefaulting to false, this determines whether your chart will be resizable. Because of the numerous event handlers this has to install code on, This feature is unlikely to work with other dynamic features (the context menu is fine however).false
resizeHandleBackgroundWith this you can specify the background color for the resize handle. If you're adjusting the position of the handle then you may need this to make the handle stand out more.null
resizableMaxwidthThis allows you to set a maximum width that the chart can be resized to.null
resizableMaxheightThis allows you to set a maximum height that the chart can be resized to.null

Key

The key properties are documented on the key documentation page.

Zoom

PropertyDescriptionDefault
zoomFactorThis is the factor that the chart will be zoomed by (bigger values means more zoom)1.5
zoomFadeInWhether the zoomed canvas fades in or not. This also can be used to control the fade in for the zoom in thumbnail mode.true
zoomFadeOutWhether the zoomed canvas fades out or not. This also can be used to control the fade in for the zoom in thumbnail mode.true
zoomHdirThe horizontal direction of the zoom. Possible values are: left, center, rightright
zoomVdirThe vertical direction of the zoom. Possible values are: up, center, downdown
zoomDelayThe delay (in milliseconds) between frames.50
zoomFramesThe number of frames in the zoom animation.10
zoomShadowWhether or not the zoomed canvas has a shadow or not.true

Events

PropertyDescriptionDefault
eventsClickIf you want to add your own onclick function you can do so by assigning it to this property. See here for details.null
eventsMousemoveIf you want to add your own onmousemove function you can do so by assigning it to this property. See here for details.null
eventsMouseoverIf you want to add your own onmouseover function you can do so by assigning it to this property. See here for details.null
eventsMouseoutIf you want to add your own onmouseout function you can do so by assigning it to this property. See here for details.null

Miscellaneous

PropertyDescriptionDefault
linewidthBy setting this to roughly 5, and setting the strokestyle to the same colour as your background colour,you will get a segment separation effect.1
variantThis can be either pie (the default), pie3d, donut or donut3d. Setting this to donut or donut3d is how you get a donut chart.pie
variantThreedDepthThis is the depth of the 3D Pie chart20
variantDonutWidthThis allows you to set how wide the donut is. It can be useful when nesting donuts.null
highlightStyleCan be either 2d, 3d, outline or a function and determines which style of segment highlighting is used in conjunction with tooltips. If its a function the function is called and no highlighting is done - ie you should do it all yourself.2d
highlightStyleOutlineWidthWhen outline highlighting for tooltips is used, this controls the width of the highlighting band.10
highlightStyleTwodFillWhen 2D highlighting for tooltips is used, this controls the color of the highlighting. The former name for this property was highlightStyleTwodColor.rgba(255,255,255,0.5)
highlightStyleTwodStrokeWhen 2D highlighting for tooltips is used, this controls the stroke color of the highlighting.rgba(255,255,255,0)
explodedThis can either be an array with the same number of elements as segments, or a single number, in which case every segment will be exploded that amount. If it's an array then only those segments will be exploded - eg [0,5,0,0]An empty array
centerpinIf you choose a linewidth greater than 1 or 2 then because of the way that HTML5 canvas renders lines you may end up with visible edges to them. So by using a centerpin you can hide these. This setting should be a number and is used as the radius of the centerpin.null
centerpinStrokeThis is used as the stroke style of the centerpin.null
centerpinFillThis is used as the fill style of the centerpin.null
cleartoThis is used in animations and effects as the default color to use when the canvas.null

 

Methods

 

obj.get(name)
An accessor that you can use to retrieve the value of properties.

 

obj.set(name, value)
An accessor that you can use to set the value of properties.

 

obj.getShape(event)

obj.getSegment() makes it easy to determine which segment of the Pie chart was clicked on. It provides:

The shape also includes textual indexes like this: shape['object'] And they are:

<script>
    RGraph.register(myGraph);
    
    myGraph.canvas.onclick = function (e)
    {
        RGraph.fixEventObject(e);
        RGraph.redraw();

        var ca  = e.target;
        var co  = ca.getContext('2d');
        var obj = ca.__object__;
        var segment = obj.getShape(e);
        
        if (segment) {
            co.fillStyle = 'rgba(255,255,255,0.5)';
            co.beginPath();            
                co.moveTo(segment[0], segment[1]);
                co.arc(segment[0], segment[1], segment[2], segment[3], segment[4], 0);
            co.stroke();
            co.fill();
            
            e.stopPropagation();
        }
    }
    
    window.onclick = function (e)
    {
        RGraph.redraw();
    }
</script>
Important Note

This method was formerly a common object method, called RGraph.getSegment(e), but has now (6th March 2011) been moved to be part of the Pie chart object.

 

 

obj.explodeSegment(index, size)

The explodeSegment() method allows you to programmatically trigger the exploding (ie the highlighting of) a particular segment. The Explode() method is used like so:

<script>
    pie = new RGraph.Pie({
        id: 'cvs',
        data: [8,9,4,6]
    }).draw();

    pie.explodeSegment(index, size);
</script>

The index argument is the zero-index segment to operate on (counting from the north axis). An the size is measured in pixels.

 

obj.getAngle(value)

This method can be used to get an appropriate angle for a value using the "scale" of the Pie chart. So if your Pie chart is showing values that go from 0-100 and your requested value is 50, this method will return an angle for the bottom of the Pie chart (ie half way around).

 

obj.on(event, func)

This method can be used to set an event listener on an object. It operates in a similar way to the jQuery .on() function - the first argument is the event you wish to attach to and the second is the handler function. For example:

.on('draw', function (obj)
{
    // Put event code here
});

The function is useful if you use method chaining when creating your charts:

var obj = new RGraph.Pie({
    id: 'cvs',
    data: [4,5,3,8,6,3]
}).on('draw', function (e, shape)
{
    // Put ondraw code here
})
.on('click', function (e, shape)
{
    // Handle click event
})
.draw()

 

The exec option and method

The exec function is documented here.

 

Animation Effects

These effects are available and can be used instead of the .draw() function. There are also generic effects available which you can see here: Generic effects and transitions
<script>
    /**
    * Optional callback function that's called when the effect is complete
    */
    function myCallback (obj)
    {
        // ...
    }

    var obj = new RGraph.Pie({
        id: 'cvs',
        data: [8,6,6,5,3,4,2],
        options: {
        }
    }).grow({frames: 60}, myCallback)
    // .implode({frames: 60}, myCallback)
    // .roundRobin({frames: 60}, myCallback)
</script>
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