We have been having some issues with fruit flies this year, and no matter how much we hide our fruit and produce they were still there.
I tried creating a funnel and putting a pieces of fruit at the bottom, it didn't work. I also tried putting apple cider vinegar in a bowl and covering it with saran wrap that had holes in it. NOTHING was working.
This is the only thing that worked for us:
As you can see, it worked! Within a few minutes of putting this out on the counter, we caught SO many fruit flies. It seems that the apple cider vinegar brings them in and the dish soap makes it slippery so they can't get out.