z-index on Chart Tooltip

[Jurgen]

We're developping a combined control where we use 3 chart donut controls. The main central one has to have the lowest z-index, 2 others are partiallyover the main one. (see picture in attachment) But it turns out that the tooltip (bottom) of the main one is also always behind the 2 other donuts. I've tried increasing the z-index of the tooltip in CSS. But this did not give a solution. (even though the webconsole showed a higher z-index for the tooltip) The only way i can get the tooltip on top is by increasing the z-index of the entire donut. But this is not allowed by the graphical design of the component.
How can i solve this problem? Any suggestions?

[Iliana Dyankova]

Hello Jurgen,

I am afraid what you would like to achieve is not supported. Actually increasing tooltip's z-index does not help because of the tooltips are in different stacking context. The only possible workaround I can suggest you is hiding the default tooltip and in the show it in the seriesHover event with a custom position (for sample code check this forum thread).   

Regards,
Iliana Nikolova
Telerik