new cieling fixture

I have a new ceiling fixture I want to install. I measured the center of the room and forced a screwdriver through to mark the spot. I then cut two 4x4s to cross brace the ceiling joists. My problem is that the only electricity is from box that feeds a closet light and two sets of outlets so the box is nearly full. I want to put a switch in, but on the opposite side of the room. Should I go into the other part of the attic to a box, then to the switch and finally to the fixture?

THanks for any help!!!!!!!

 

If the only problem is the box having too much in it you can go to your local electrical supply house and buy what is called an extention ring, this will allow more wires to be added and should provide you with adequate space. The question is how much is already on that circuit just what you described or more? Take into consideration all that is going to be or might be run off the circuit. Remember if you run to the fixture first then to the switch the white wire is not to be used for switching, so running a three wire from fixture to switch is a good idea, this was you can use the two coloured wire for the switch and wirenut off the white and have it there just in case someday you may need a neutral at that point to carry power on to something else.