Elements

Elements

While chart types provide settings to configure the styling of each dataset, you sometimes want to style all datasets the same way. A common example would be to stroke all of the bars in a bar chart with the same colour but change the fill per dataset. Options can be configured for four different types of elements: arc, lines, points, and rectangles. When set, these options apply to all objects of that type unless specifically overridden by the configuration attached to a dataset.

Global Configuration

The element options can be specified per chart or globally. The global options for elements are defined in Chart.defaults.global.elements. For example, to set the border width of all bar charts globally you would do:

Chart.defaults.global.elements.rectangle.borderWidth = 2;

Point Configuration

Point elements are used to represent the points in a line, radar or bubble chart.

Global point options: Chart.defaults.global.elements.point.

Name	Type	Default	Description
`radius`	`number`	`3`	Point radius.
`pointStyle`	`string\|Image`	`‘circle’`	Point style.
`rotation`	`number`	`0`	Point rotation (in degrees).
`backgroundColor`	`Color`	`‘rgba(0, 0, 0, 0.1)’`	Point fill color.
`borderWidth`	`number`	`1`	Point stroke width.
`borderColor`	`Color`	`‘rgba(0, 0, 0, 0.1)’`	Point stroke color.
`hitRadius`	`number`	`1`	Extra radius added to point radius for hit detection.
`hoverRadius`	`number`	`4`	Point radius when hovered.
`hoverBorderWidth`	`number`	`1`	Stroke width when hovered.

Point Styles

The following values are supported:

'circle'
'cross'
'crossRot'
'dash'
'line'
'rect'
'rectRounded'
'rectRot'
'star'
'triangle'

If the value is an image, that image is drawn on the canvas using drawImage.

Line Configuration

Line elements are used to represent the line in a line chart.

Global line options: Chart.defaults.global.elements.line.

Name	Type	Default	Description
`tension`	`number`	`0.4`	Bézier curve tension (`0` for no Bézier curves).
`backgroundColor`	`Color`	`‘rgba(0, 0, 0, 0.1)’`	Line fill color.
`borderWidth`	`number`	`3`	Line stroke width.
`borderColor`	`Color`	`‘rgba(0, 0, 0, 0.1)’`	Line stroke color.
`borderCapStyle`	`string`	`‘butt’`	Line cap style. See MDN.
`borderDash`	`number[]`	`[]`	Line dash. See MDN.
`borderDashOffset`	`number`	`0.0`	Line dash offset. See MDN.
`borderJoinStyle`	`string`	`‘miter’`	Line join style. See MDN.
`capBezierPoints`	`boolean`	`true`	`true` to keep Bézier control inside the chart, `false` for no restriction.
`cubicInterpolationMode`	`string`	`‘default’`	Interpolation mode to apply. See more…
`fill`	`boolean\|string`	`true`	How to fill the area under the line. See area charts.
`stepped`	`boolean`	`false`	`true` to show the line as a stepped line (`tension` will be ignored).

Rectangle Configuration

Rectangle elements are used to represent the bars in a bar chart.

Global rectangle options: Chart.defaults.global.elements.rectangle.

Name	Type	Default	Description
`backgroundColor`	`Color`	`‘rgba(0, 0, 0, 0.1)’`	Bar fill color.
`borderWidth`	`number`	`0`	Bar stroke width.
`borderColor`	`Color`	`‘rgba(0, 0, 0, 0.1)’`	Bar stroke color.
`borderSkipped`	`string`	`‘bottom’`	Skipped (excluded) border: `‘bottom’`, `‘left’`, `‘top’` or `‘right’`.

Arc Configuration

Arcs are used in the polar area, doughnut and pie charts.

Global arc options: Chart.defaults.global.elements.arc.

Name	Type	Default	Description
`angle` - for polar only	`number`	`circumference / (arc count)`	Arc angle to cover.
`backgroundColor`	`Color`	`‘rgba(0, 0, 0, 0.1)’`	Arc fill color.
`borderAlign`	`string`	`‘center’`	Arc stroke alignment.
`borderColor`	`Color`	`‘#fff’`	Arc stroke color.
`borderWidth`	`number`	`2`	Arc stroke width.