# Pie charts documentation

- Example
- Properties
- Methods

## Example

    <script>
        window.onload = function ()
        {
            // The data to be shown on the Pie chart
            var data = [564,155,499,611,322];

            // Create the Pie chart. The arguments are the canvas ID and the data to be shown.
            var pie = new OfficeExcel.Pie('myPie', data);

            // Configure the chart to look as you want.
            pie.Set('chart.labels', ['Abc', 'Def', 'Ghi', 'Jkl', 'Mno']);
            pie.Set('chart.linewidth', 5);
            pie.Set('chart.stroke', 'white');

            // Call the .Draw() chart to draw the Pie chart.
            pie.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');

- Margins
- Colors
- Labels and text
- Titles
- Shadows
- Interactive features
- Key
- Zoom
- Events
- Miscellaneous

### Margins

chart.gutter.left
The left gutter of the chart, (the gutter is where the labels and title are)).
Default: 25
chart.gutter.right
The right gutter of the chart, (the gutter is where the labels and title are).
Default: 25
chart.gutter.top
The top gutter of the chart, (the gutter is where the labels and title are).
Default: 25
chart.gutter.bottom
The bottom gutter of the chart, (the gutter is where the labels and title are).
Default: 25

### Colors

chart.colors
Colors to be used for the pie segments.
Default: ['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']
chart.strokestyle
The color of the seperating lines. By setting this to your background color, and setting the linewidth to approx. 5, it will make the pie chart look "exploded".
Default: #999

### Labels and text

chart.text.size
The size of the text (in points).
Default: 10
chart.text.font
The font used to render the text.
Default: Verdana
chart.text.color
The color of the labels.
Default: black
chart.labels
An array of labels to be used for the chart.
Default: [] (an empty array)
chart.labels.sticks
Stipulates that sticks for the labels are shown.
Default: false
chart.labels.sticks.color
Sets the color of the label sticks.
Default: #aaa
chart.labels.sticks.length
Sets the length of the label sticks.
Default: 7

### Titles

chart.title
The title of the pie chart.
Default: none
chart.title.font
The font that the title is rendered in. If not specified the chart.text.font setting is used (usually Verdana)
Default: null
chart.title.size
The size of the title. If not specified the size is usually 2pt bigger than the chart.text.size setting.
Default: null
chart.title.bold
Whather the title is bold or not.
Default: true
chart.title.background
The background color (if any) for the title.
Default: null
chart.title.color
The color of the title.
Default: black
chart.title.hpos
This allows you to completely override the horizontal positioning of the title. It should be a number between 0 and 1, and is multiplied with the whole width of the canvas and then used as the horizontal position.
Default: null
chart.title.vpos
This allows you to completely override the vertical positioning of the title. It should be a number between 0 and 1, and is multiplied with the gutter and then used as the vertical position. It can be useful if you need to have a large gutter.
Default: null

### Shadows

chart.shadow
Whether a simple shadow effect is applied.
Default: false
chart.shadow.color
The color of the shadow.
Default: rgba(0,0,0,0.5)
chart.shadow.blur
The severity of the shadow blurring effect.
Default: 3
chart.shadow.offsetx
The X offset of the shadow.
Default: 3
chart.shadow.offsety
The Y offset of the shadow.
Default: 3

### Interactive features

chart.tooltips
An array of tooltips, starting from the middle right (ie east) axis, and going clockwise sequentially.
Default: [] (An empty array)
chart.tooltips.event
This can be onclick or onmousemove and determines which event is used for tooltips.
Default: onclick
chart.tooltips.effect
The animated effect used for showing tooltips. Can be either fade or expand.
Default: fade
chart.tooltips.css.class
This is the name of the CSS class the chart uses.
Default: OfficeExcel_tooltip
chart.tooltips.override
If 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 page
Default: null
chart.contextmenu
An array of context menu items. More information on context menus is here.
Default: [] (An empty array)
chart.annotatable
Whether annotations are enabled for the chart (ie you can draw on the chart interactively.
Default: false
chart.annotate.color
If you do not allow the use of the palette, then this will be the only colour allowed for annotations.
Default: black
chart.resizable
Defaulting 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).
Default: false
chart.resize.handle.background
With 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.
Default: null

### Key

chart.key
An array of key information.
Default: [] (An empty array)
chart.key.background
The color of the key background. Typically white, you could set this to something like rgba(255,255,255,0.7) to allow people to see things behind it.
Default: white
chart.key.halign
Instead of specifying the exact x/y coordinates, you can use this property to simply specify whether the key hould be aligned left or right.
Default: right
chart.key.position
Determines the position of the key.Either graph (default), or gutter.
Default: graph
chart.key.position.x
This allows you to specify a specific X coordinate for the key.
Default: null
chart.key.position.y
This allows you to specify a specific Y coordinate for the key.
Default: null
chart.key.position.gutter.boxed
If you have the key in gutter mode (ie horizontal), this allows you to give a background color.
Default: true
chart.key.shadow
Whether a small drop shadow is applied to the key.
Default: false
chart.key.shadow.color
The color of the shadow.
Default: #666
chart.key.shadow.blur
The extent of the blurring effect used on the shadow.
Default: 3
chart.key.shadow.offsetx
The X offset of the shadow.
Default: 2
chart.key.shadow.offsety
The Y offset of the shadow.
Default: 2
chart.key.rounded
This controls whether the corners of the key (in graph mode) are curved. If the key is gutter mode, this has no effect.
Default: false
chart.key.color.shape
This can be square, circle or line and controls how the color indicators in the key appear.
Default: square
chart.key.linewidth
The line width of the surrounding border on the key.
Default: 1
chart.key.interactive
This option enables the facility to click on the pie chart to highlight (explode only) the relevant segment.
Default: false

### Zoom

chart.zoom.mode
Can be used to control whether the zoom is in thumbnail or canvas mode. Possible values are: thumbnail and canvas.
Default: canvas
chart.zoom.factor
This is the factor that the chart will be zoomed by (bigger values means more zoom)
Default: 1.5
chart.zoom.fade.in
Whether the zoomed canvas fades in or not. This also can be used to control the fade in for the zoom in thumbnail mode.
Default: true
chart.zoom.fade.out
Whether the zoomed canvas fades out or not. This also can be used to control the fade in for the zoom in thumbnail mode.
Default: true
chart.zoom.hdir
The horizontal direction of the zoom. Possible values are: left, center, right
Default: right
chart.zoom.vdir
The vertical direction of the zoom. Possible values are: up, center, down
Default: down
chart.zoom.delay
The delay (in milliseconds) between frames.
Default: 50
chart.zoom.frames
The number of frames in the zoom animation.
Default: 10
chart.zoom.shadow
Whether or not the zoomed canvas has a shadow or not.
Default: true
chart.zoom.thumbnail.width
When the zoom is in thumbnail mode, this is the width (in pixels) of the thumbnail.
Default: 75
chart.zoom.thumbnail.height
When the zoom is in thumbnail mode, this is the height (in pixels) of the thumbnail.
Default: 75
chart.zoom.thumbnail.fixed
When the zoom is in thumbnail mode, you can use this property to fix the zoom in the top left corner instead of it following the cursor around.
Default: false
chart.zoom.background
Defaulting to true, this determines whether the zoom has a dark, semi-opaque background that covers the entire web page.
Default: true

### Events

chart.events.click
If you want to add your own onclick function you can do so by assigning it to this property. See here for details.
Default: null
chart.events.mousemove
If you want to add your own onmousemove function you can do so by assigning it to this property. See here for details.
Default: null

### Miscellaneous

chart.align
Whether to left, center or right align the pie chart.
Default: center
chart.linewidth
By setting this to roughly 5, and setting the strokestyle to the same colour as your background colour,you will get a segment separation effect.
Default: 1
chart.variant
This can be either pie (the default) or donut. Setting this to donut is how you get a donut chart.
Default: pie
chart.highlight.style
Can be either explode, 2d or 3d and determines which style of segment highlighting is used in conjunction with tooltips.
Default: 3d
chart.highlight.style.2d.fill
When 2D highlighting for tooltips is used, this controls the color of the highlighting. The former name for this property was chart.highlight.style.2d.color.
Default: rgba(255,255,255,0.5)
chart.highlight.style.2d.stroke
When 2D highlighting for tooltips is used, this controls the stroke color of the highlighting.
Default: rgba(255,255,255,0)
chart.explode
This 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]
Default: [] (an empty array)

## Methods

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

- Originating X coordinate
- Originating Y coordinate
- The radius of the segment
- The starting angle (measured in radians)
- The ending angle (measured in radians)
- The zero-indexed segment number

    <script>
        OfficeExcel.Register(myGraph);

        myGraph.canvas.onclick = function (e)
        {
            OfficeExcel.FixEventObject(e);
            OfficeExcel.Redraw();

            var canvas  = e.target;
            var context = canvas.getContext('2d');
            var obj     = canvas.__object__;
            var segment = obj.getSegment(e);

            if (segment) {
                context.fillStyle = 'rgba(255,255,255,0.5)';
                context.beginPath();
                    context.moveTo(segment[0], segment[1]);
                    context.arc(segment[0], segment[1], segment[2], segment[3], segment[4], 0);
                context.stroke();
                context.fill();

                e.stopPropagation();
            }
        }

        window.onclick = function (e)
        {
            OfficeExcel.Redraw();
        }
    </script>

obj.getShape(event)

This method is an alternate name for the above method but has a generic name that is the same acoss the various libraries.

obj.Explode(index, size)

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

    <script>
        myObj = new OfficeExcel.Pie('cvs', [8,9,4,6]);
        myObj.Draw();

        myObj.Explode(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.

Important Note

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