Expressions are called too many times

[awallat]

Description
When using an expression-function to dynamically set the required-property for example, this function gets called a lot of times. I have got a big form and it suffers from performance issues, especially on slower machines.

In my simple example having just one field, the expression function gets called 4 times, when setting the model to a new value. Calling this.formState.resetModel(...) results in 11 calls.

Minimal Reproduction
https://stackblitz.com/edit/angular-mfw4c7?file=src%2Fapp%2Fapp.component.html

Your Environment

• Angular version: 16.2.3
• Formly version: 6.2.1

[aitboudad]

We'll try to see if we can reduce the number of calls, please note if you're looking for a very optimized solution you may consider passing an Observable to expressions which will be called only when the Observable value is changed.

[aitboudad]

This issue has been fixed and released as part of v6.2.2 release.

Please let us know, in case you are still encountering a similar issue/problem.
Thank you!

[aitboudad]

I have got a big form and it suffers from performance issues, especially on slower machines.

To improve rendering time, use virtual scroll stackblitz.com/edit/angular-rfwvp6