Support for callback function for grid.tooltip.formatter?

[jtpio]

The official Echarts docs mention the use of a callback function for grid.tooltip.formatter as a second option: https://echarts.apache.org/en/option.html#grid.tooltip.formatter

However it's not clear if such functionality could be supported by the EChartsRawWidget, since the function is expected to be in JavaScript in the original Echarts library.

Maybe a good tradeoff could be to allow passing a JS function as a raw string, to be evaluated and executed on the frontend.

[trungleduc]

Yep, supporting JS callback is quite tricky, even by using the raw JS string since most JS classes are auto-generated.
If the number of callback options is not too much, I could do it manually, but it is not on my priority list. For the next version, I want to focus on supporting chart action (https://echarts.apache.org/en/api.html#action)