The floating notification should just be a banner across the top of the entire screen, with a text editing bar on the bottom of it, and if you press the text edit bar it'll open the keyboard for a quick reply. If you swipe right, it'll dismiss the notification. Swipe left could be an option that the user sets to delete, remind later, or whatever.

As it is now the floating notification is functionless which is frustrating when i see other apps with functions, like the stock Android and iphone messagers.