Is their going to be a dark knight sequel ???

at the end it seems that there are alot of unanswered questions....like what happens to the joker....are they just going to put him in prison....thats it...what happens to lucius fox....how could christopher nolan end this film with batman appearing as the bad guy to the people.....he should have made 2 batman films back to back...so is there going to be a sequel related to the latest one....