# Preventing remount of custom renderer when updating UI schema

**URL:** <https://jsonforms.discourse.group/t/preventing-remount-of-custom-renderer-when-updating-ui-schema/2775>\
**Category:** General\
**Created:** [September 17, 2025, 7:47am UTC](https://jsonforms.discourse.group/t/preventing-remount-of-custom-renderer-when-updating-ui-schema/2775 "2025-09-17T07:47:15Z")\
**Posts on this page:** 2\
**Page:** 1

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**Author:** ![jenn4453](https://avatars.discourse-cdn.com/v4/letter/j/b9e5f3/32.png) [@jenn4453](https://jsonforms.discourse.group/u/jenn4453)\
**Post date:** [September 17, 2025, 7:47am UTC](https://jsonforms.discourse.group/t/preventing-remount-of-custom-renderer-when-updating-ui-schema/2775/1 "2025-09-17T07:47:15Z")

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I have a use case where my `schema` and `uischema` contain variables that reference the current `formData`.

When `formData` changes, I resolve those variables outside of JSON Forms. If any referenced data changed, I re-generate the resolved `schema`/`uischema` and pass them back into JSON Forms.

This generally works fine. The problem is with a custom renderer I wrote for a `Select` component:

- Every time the `uischema` changes, my custom renderer is **remounted**.

- This causes the Select to flicker and temporarily lose its value.

- I can re-pass the value so the data isn’t lost, but the flicker from the remount is still very noticeable.

**Question:**  
Is there a way to update a `uischema` in JSON Forms without triggering a full remount of the custom renderer? Or alternatively, is there a recommended approach to handle dynamic `uischema` updates without causing this kind of flicker?

Thanks!

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**Author:** ![lucas-koehler](https://yyz2.discourse-cdn.com/free1/user_avatar/jsonforms.discourse.group/lucas-koehler/32/336_2.png) [@lucas-koehler](https://jsonforms.discourse.group/u/lucas-koehler)\
**Post date:** [September 17, 2025, 8:03am UTC](https://jsonforms.discourse.group/t/preventing-remount-of-custom-renderer-when-updating-ui-schema/2775/2 "2025-09-17T08:03:27Z")

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Hi @jenn4453 ,

unfortunately there is no way to update the schema or ui schema without triggering a full re-render. Typically a re-render should not trigger a remount if the layout and the key of the renderer stays the same. If you change the layout structure down to where the custom renderer is rendered, the remount is expected.

> Or alternatively, is there a recommended approach to handle dynamic `uischema` updates without causing this kind of flicker?

This depends on your use case, i.e. what kind of dynamic updates to the uischema and schema you are doing. Could you elaborate on that?

For instance, select options to display can be directly loaded by the custom renderer or handed into it via a context (e.g. React context in case you use the React renderers).

Best regards,

Lucas