Greetings from the Syncfusion.
We have prepared the sample with custom tooltip based on our documentation sample. But we are unable to reproduce the reported issue in that sample. The tooltip will be shown perfectly in the Grid. So we have attached the sample for your reference and that can be download from the below link,
Still, if you have facing the same issue please share the following details. This will help us to provide the solution as early as possible,
- In your query, you have mentioned queryCellInfo event not working. So please share the details about what issue you have faced while using this event?.
- Ensure whether the queryCellInfo event will be triggered or not at the initial Grid rendering.
- If queryCellInfo event will be triggered, then please ensure your condition that you have provided to create the tooltip in the queryCellInfo event.
- If you have faced any script error in the browser console, then please share the screenshot of the error.
- Syncfusion package version.