Capture lock or unlock meta fields

Hi,

I've a requirement to lock or unlock  the fields based on some condition.say if field1 value exits then lock all remaining fields else unlock

for this I implemented the logic in function Document Selected

if(FieldrID !=null && Field !=" ")

   {

    print("inside IF");

    fieldDefs.findByName(fieldsToCopy[fieldIdx]).locked = true;

   

    print("After inside IF");

   }

   else  {

    print("else Starting---->");

   

    fieldDefs.findByName(fieldsToCopy[fieldIdx]).locked = false;

    print("after else***---->");

   }

Using the above code base, this is not changing the locked value from true to false, Once true then it is keeping lock for all