Wednesday, March 31, 2010

flash.now - did you know?

Well, I didn't know this until late. If you are like me, you have often wondered when you saw those unwanted flash messages appearing after a request, sometimes after ajax requests when you do a redirect, all on a sudden that flash shows up!
Well, as you have thought, the Ruby on Rails people have solved this problem way before now. The solution is to wisely use flash.now[] and flash[]. Here are a few tips:

Use flash.now[] when you are flashing:

  • on ajax requests
  • before a call to render :action => :my_action, as often found in failure cases of create and update actions
Use flash[] when you are flashing:

  • before a redirect_to, often found in the success cases of create and update actions
In general, use flash.now[] when you don't want to carry over the flash to the next http request and flash[] otherwise. The FlashHash class has more detail on this at the ruby on rails API page. Hope this helps you to get rid of those annoying and often embarrassing out-of-context flash messages!