Upload & Sell: Off
Deborah has the right idea. Because I wear glasses with large lenses to improve my peripheral vision my eyes are more than a centimeter from the center of the corrective lenses. This means I cannot quite see the entire field of view in the viewfinder while wearing the glasses. Also, light leak reduces the quality of what I do see. So I use the diopter adjustment and work without glasses.
If I am taking pictures at an event where I need to switch back and forth between scanning the area around me and using the viewfinder, I attach a strap to my glasses, like the kind people use for white water rafting (what Deborah called a "la Loop"), so I can quickly pull my glasses off my face to take a photo. This has worked well for me.
However, if your eyes tolerate contacts, that is the best solution.