This is a question about bike bells and if an audible warning can be launched with a shifter ?

  1.  I'm often sharing paths with hikers and a loud bell is essential. I've seen Treks speaker bell with 8 sounds. Is there a way to sync a bell feature into my garmin / shifter interface ? I scroll through garmin screens with my shimano shifters....it would be safe and efficient if this was possible. Are there such pairings out there ?