One of my cities isn't growing

Is that 80 food or 80 excess food?

This issue is due to lacking information on the part of the UI. Just open up the city details screen, and on the third column hover over food - it will tell you how much food your city produces in total, how much food is taken up by current population and what's left for expansion. 

When out of food, you can research civics technologies that provide extra food per grain, build some buildings to the same effect, capture via outposts any food-producing terrain bonus (sends the food to the closest city), or rely on late-game spells. 

I had just finished building 2 different food increasing buildings and researched 2 different food producing techs so that my city would grow.  in the city details screen I had 80 excess food for growth and my city was still saying I didn't have any food.

Hit the enter button. It takes a turn to reset the growth when you just produced a food building.

thanks impinc.  i knew that and did that.  two turns later i'm still at 80 excess food and zero growth.  i'm beginning to think it's a bug.  if no one else is having this issue than maybe i just need to re download and try the install again.

i believe the issue cropped up after I built the docks in that city.  after that I noticed the issue.  it was growing fine before that.

On an updated note:  I just reloaded my game and for some reason, shutting down the game and restarting it fixed the issue.  my city is now growing properly again.  so apparently it is a bug of some sort.

Good find, then. If I see it happen like you describe, I'll save the game so the devs can check it out.

next time a screenshot would be nice, and if repeatable a savegame

Sincerely
~ Kongdej