The documentation for hightlightProperty(withKey:identifier:) describes the parameter "key" as the "Key of the property to highlight." I believe that refers to the CNKeyDescriptor, such as CNContactGivenNameKey, which can cast from a type CNKeyDescriptor to String.
The documentation for identifier is "the value to highlight". I believe an example of that would be "John" as the given name.
Am I correct about all this?
In any case, I'm not able to highlight an email property when I use CNContactEmailAddresses as the key, and an actual email address as the identifier. I have also tried using the identifier property of CNLabeledValue<NSString>, which is how an email address is stored.
I can't find anything on the internet to explain this. I didn't even find a similar question, except my own question asking this exact same question about two months ago.
Anyone have any idea or a good answer for this?