I had a similar problem, which was because I had two versions of the printer installed (USB and wireless).
When you select print, you get an initial dialogue box to select your Canon MG3200. Make sure you select the wireless one (second option for me). A second dialogue box with printer options also shows up. Make sure this is also the wireless printer (again, second option for me).
I was getting the offline error because I was only changing the printer in the first dialogue box, but not the second one.