"You could use that Future instead of using a periodic timer."....How about in the case of multiple files being selected? I could create the new selection in the last index of the array...but if the first file is large and the last one is small...there's no guarantee that the last (small) won't finish before the first one (large)...right?

Maybe I just need to brush up on my dart...but I'll try to see if there's a better construct for awaiting multiple futures...