You'll never believe that it's so simple.
Take a disposible cup and place a piece of ripe fruit into it. Cover tightly with plastic wrap. Prick with a sharp pencil the plastic in about 5 place and watch what happens. The flies go into the small holes and can't get out. Dispose outside into the garbage.
I know it's gross, but it's so good not to have the fruit flies in the kitchen.
Thanks, Emily for sharing this great idea.