Annotations are containers for images, text blocks, and custom content. Annotations can help deliver a more refined user-experience and can improve analysis and readability (by displaying additional information for visualized data).
To create annotations, populate the PieChart's annotations array. Each object in the array configures an individual annotation. To specify settings for all annotations, use the commonAnnotationSettings object. Individual settings take precedence over common settings.
You can set each annotation type property to "text", "image", or "custom". In this demo, the type used for all annotations is "image".
Annotations can deliver more information if you add tooltips. A tooltip appears when users hover the mouse pointer over an annotation. This demo illustrates how you can implement a tooltip with custom content via the tooltipTemplate property.
For more information on annotation settings, refer to the annotations help topic.