If the AIO allows you to have an input sure.
It will act like any other monitor.
I had a PS3 connected to my Samsung 2494HS monitor
Thing is most AIO PCs have output ports
As they are just a large LCD panel with minimal circuitry, so no adjusting brightness, color,or any other menu type settings one would get with a normal monitor, they will have a LVDS internal connection, some might have a DVI.
Since I have seen an acer that had a normal motherboard inside with a video card riser which had the monitor connected via VGA but this one of those old red and silver acer AIO POS units.