The court takes into consideration several factors when awarding custody. Being unemployed is not one of them. The number one factor that the court looks to when making decisions involving children is what is in the best interest of the child. While not having employment may be a negative factor during your child custody case, you can still get custody of your child as long as the court determines that it is in the child best interest to stay with you.
Depending on the custody arrangement, you (the unemployed parent) may be entitled to receive child support from the other parent in order to help you to take care of your child.

It is the courts position that both parents have an obligation to take care of the child. The court would not want to see the child become the responsibility of the state, and thus would require you to eventually get a job so that you are able to support the child. Remember that taking care of a child is the responsibility of both parents.