depends on hen only. All hens lay eggs regardless whether there is a roo around or not. I believe whatever color egg the hen came out of is the color it will lay, not 100% sure but I think that's right.
Actually, it can differ, but the mother's egg shell color will be an influence. As an example, an olive-egger hen with an EE mother and a Marans father can lay an olive colored egg, even though she hatched from a blue-green egg. The blue-green and the dark brown combine to make olive.
If you are talking about the roo that is in with your hens, then no he is not a factor in the color egg they lay. He will pass on egg color traits to his offspring. A Marans roo out of a very dark egg will pass that on to his kids, or an Ameraucana roo out of a blue egg will pass that on.