Ok... That's what I've ended up doing.. However I have a field in a repeating table.. My code sets that field to true, it's false by default.. I can't seem to setup the condition on confitional formating rule correctly.. I want the rule to disable the field only in rows where the field's attribute = true.. Meaning if row 1 is true the field is disalbed but it row 2 is fals ethe field is enabled and row 3 is true the disable, etc...
This is the expression I have tried: and several other variants..
/my:myFields/my:RequestData/my:ItemSyteLineInfo/my:ItemSyteLineInfo_BOM/my:ItemSyteLineInfo_BOM_Operations/my:ItemBOMOpOperation[current()]/@my:IsExisting = "true"