I need to create an EL that turns absence start date "ready only" if the status is approved

Summary:

I need to create an EL that turns absence start date "ready only" if the status is approved

Content (required):

I need to create an EL that turns absence start date "ready only" if the status is approved because the system we are integrating with does not allow change because start date is key. I tried to use

#{bindings.AbsenceStatusCd.inputValue =='APPROVED'}  but it doen´t do anything.

Version (include the version you are using, if applicable):

21D

Code Snippet (add any code snippets that support your topic, if applicable):

#{bindings.AbsenceStatusCd.inputValue =='APPROVED'}