Moving into a new building and wanting to wire a new ceiling fixture into the box built into the ceiling. The fixture has only black, white, and an uninsulated copper wire. It does have green screws which are not hooked up to anything also. The fixture is to be operated by a wall switch—one switch only, not two—nothing else. The ceiling connection box has red, white, black and green wires. If you connect black to black, white to white, and uninsulated to green (ground I assume) the light turns on but the wall switch does not operate it; the wall switch will not turn it off. The red wire obviously is tied to the switch control. How to connect it into all this? What to do at this point? Not at all clear!!
Connect fixture black to ceiling box red instead
From what you've done so far, it's clear that the black wire in your ceiling box is an always-hot wire. So, we can safely assume by elimination that the red wire must be the switched-hot you're looking for, since we already know what neutral and ground are as well.