Jump Anim Need to play only when Grounded

I just started scripting and I have a script made for my gun to play its jumping animation when space is pushed, but im able to play it twice when im not grounded.
I'm trying to make my "jumpanimation" (which is attached to my gun) only play when my character is grounded and when the jump button is pushed. Is there a simple way to do that, or an alternative? I also have an "idleanimation" and a "walkinganimation" that i would like to include in the script. Thanks