After short circuit, light switch no longer has power
It might just be that when the wires shorted together and the breaker tripped, there is now some soot/debris on the conductors so they aren't making good contact to the switch terminals now. Clean the wire with some emery cloth / wire brush (WITH THE BREAKER OFF!) and try it again.

It's POSSIBLE that in making that short, you fried a wire deep in the wall, in which case it becomes a bigger job for an electrician.