I have a user registration form, which containts many fields and there are many conditions between them. For example I disable some fields for already registred users such as email,login,password. Also I have a menu item to edit the profile and all it's fields can be edited except login, email and password. So I need to have one more menu item which will allow user to edit only these fields: login, email and password.
Thanks Bucklash, I tried it but it doesnt work as needed.
Ideally I imagine it like this: In adminpannel creat a copy of User type with only standart joomla fields and in SiteForm set for all fiels live value as current user. Then output this form in new menu item. Actually I got the right results in a form, but after submitting the seblod tries to create a new user. So, the questions are how to stop creation a new user and how to change the current user with new values from this form? I think it could be conrolled by the BeforeStore or AfterStore plugin, but I dont know how,
To hide or show fields you can use overrides option in menu (e.g. set field to Hidden&Anonimous variation) or use restrictions and/or permissions.
You can as well combine the above methods and apply the to the duplicate fields, eg. you have one field with normal form and a copy with read-only variation and show form to administrators and read-only copy to all others.