Unplanned
Last Updated: 10 Aug 2026 11:59 by ADMIN
Andrei
Created on: 03 Aug 2026 14:23
Category: KendoReact
Type: Feature Request
1
Scheduler. Improving customSlot/customItem mechanics to eliminate rerender boilerplate

Problem:

Currently, passing props directly through customSlot and customItem triggers numerous unnecessary component rerenders. To mitigate this, official support recommends passing props via React Context and wrapping customSlot/customItem in React.memo, while explicitly specifying which props should trigger a rerender upon changing. These additional workarounds introduce a poor developer experience. It is initially unclear what needs to be implemented, and it introduces a high maintenance overhead, as any future component extensions or changes require manual monitoring to prevent regressions.

Proposal:

Please optimize the internal mechanics of customSlot/customItem so that they handle updates efficiently out of the box, eliminating the need for this boilerplate code. Below is an example that implements all the current recommended workarounds to avoid unnecessary redraws:

https://stackblitz.com/edit/react-kr5cmxga-dp96seni?file=app%2FcustomSlot.tsx 

1 comment
ADMIN
Vessy
Posted on: 10 Aug 2026 11:59

Hi,

Thanks a lot for the submitted feature request, Andrei. We will monitor the interest in it closely and plan it for implementation based on the demand for it.

Regards,
Vessy
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