I wonder whether he thinks that eating is more fun when you play.  My trainer told me to let her skip a meal or two, if she wants, just to learn that when it's time to eat it's really time to eat.  I hated to do that, but it worked.
 
If I were you, I might also experiment with adding something interesting to her food, if it's just kibble.  When Kasey wasn't eating (and she was with the trainer for a week), she suddenly became interested when something else was sprinkled on her food -- a few bites of chicken with water (chicken soup, doggie style!), or a little cottage cheese mixed in. 
You might be able to find out if it's the food she doesn't like.... or simply if she's getting into the bad habit of thinking that food-time is play-time.  I heard that you have to be careful with the feeding by hand thing, because Yorkies can get used to it and can stubbornly insist that's the only way they'll eat. 
I know it's tempting to do whatever the pup wants!  I'm a total pushover! 
Let me know how it goes.... Good luck!!! 
Kim (PS: Kasey scarfed down her whole meal tonight!  Exercise does also help to make them more hungry....)