Jacob,
You can solve it as shown in example
We just looked into your JSON API and its returning 0 every time. If you can make it return some data we would be able help you in updating the chart.
You cannot send function as part of JSON data directly. Though you can serialize function on the server before sending, this is generally not suggested. Instead we suggest adding these event handlers on the client side after receiving the json data.
This issue has been fixed in the latest release (v1.8.0 Beta 5). Please download the same from here and let us know your feedback.
Here is the jsFiddle with working code.
Thanks for reporting the issue.
— Vishwas R
Sorry, we don’t have event support for axis labels yet. But we consider it in future.