Hide instruments

Hi again,
questions questions questions...
I wonder how I can hide instruments in the score that aren't playing in each system. I found in the User Guide how you hide an instrument for the entire score, but I wanna hide instruments when their not playing, and show them again when they are.
questions questions questions...
I wonder how I can hide instruments in the score that aren't playing in each system. I found in the User Guide how you hide an instrument for the entire score, but I wanna hide instruments when their not playing, and show them again when they are.