The property is used when there are multiple pies. By default, it's undefined and the control perform layout automatically.

Set this property to a string to specify the name of the property that contains an item's child items (e.g. 'items').

Set this property to an array containing the names of the properties that contain child items at each level, when the items are child items at different levels with different names (e.g. [ 'accounts', 'checks', 'earnings' ]).

The inner radius is measured as a fraction of the pie radius.

The default value for this property is zero, which creates a pie. Setting this property to values greater than zero creates pies with a hole in the middle, also known as doughnut charts. The valid range for inner radius is from 0 to 1.

The default value for this property is 0.

See also the selectedItemPosition and selectionMode properties.

The default value for this property is false.

Disabled controls cannot get mouse or keyboard events.

If specified, the function should take three parameters: the chart's IRenderEngine responsible for rendering elements on the chart, a HitTestInfo parameter that describes the element being rendered, and a function that provides the default rendering for the item.

For example:

itemFormatter: function (engine, hitTestInfo, defaultRenderer) {
  var ht = hitTestInfo,
      binding = 'downloads';

  // check that this is the right series/element
  if (ht.series.binding == binding && ht.pointIndex > 0 &&
      ht.chartElement == ChartElement.SeriesSymbol) {

    // get current and previous values
    var chart = ht.series.chart,
        items = chart.collectionView.items,
        valNow = items[ht.pointIndex][binding],
        valPrev = items[ht.pointIndex - 1][binding];

    // add line if value is increasing
    if (valNow > valPrev) {
      var pt1 = chart.dataToPoint(ht.pointIndex, valNow),
          pt2 = chart.dataToPoint(ht.pointIndex - 1, valPrev);
      engine.drawLine(pt1.x, pt1.y, pt2.x, pt2.y, null, {
        stroke: 'gold',
        strokeWidth: 6
      });
    }
  }

  // render element as usual
  defaultRenderer();
}

{@sample: Chart/LineArea/CustomLineSegments/purejs Example}

The offset is measured as a fraction of the pie radius.

The default value for this property is 0.

The following options are supported:

htmlText: If true, it allows to use HTML tags in chart text elements like header, footer legend, axis and data labels. The default value is false.

chart.header: 'Country GDP';
chart.options = {
  htmlText: true
}

The array contains strings that represents CSS colors. For example:

// use colors specified by name
chart.palette = ['red', 'green', 'blue'];
// or use colors specified as rgba-values
chart.palette = [
  'rgba(255,0,0,1)',
  'rgba(255,0,0,0.8)',
  'rgba(255,0,0,0.6)',
  'rgba(255,0,0,0.4)'];

There is a set of predefined palettes in the Palettes class that you can use, for example:

chart.palette = Palettes.coral;

The plot margin represents the area between the edges of the control and the plot area.

By default, this value is calculated automatically based on the space required by the axis labels, but you can override it if you want to control the precise position of the plot area within the control (for example, when aligning multiple chart controls on a page).

You may set this property to a numeric value or to a CSS-style margin specification. For example:

// set the plot margin to 20 pixels on all sides
chart.plotMargin = 20;
// set the plot margin for top, right, bottom, left sides
chart.plotMargin = '10 15 20 25';
// set the plot margin for top/bottom (10px) and left/right (20px)
chart.plotMargin = '10 20';

The default value is false, which causes angles to be measured in the clockwise direction.

The default value for this property is false.

Offsets are measured as a fraction of the pie radius.

The default value for this property is 0.

Setting this property to a value other than 'None' causes the pie to rotate when an item is selected.

Note that in order to select slices by clicking the chart, you must set the selectionMode property to 'Point'.

The default value for this property is Position.None.

The default value for this property is SelectionMode.None.

Angles are measured clockwise, starting at the 9 o'clock position.

The default value for this property is 0.

tabindex attribute value can be defined statically for a Wijmo control by specifying it on the control's host HTML element. But this value can't be changed later during application lifecycle, because Wijmo controls have complex structure, and the control may need to propagate this attribute value to its internal element to work properly.

Because of this, to read or change control's tabindex dynamically, you should do it using this property.

The titles are shown above each pie chart when multiple properties are specified in binding. If the property is not set (undefined) the property names are used as pie titles.