My son LOVES the TV, Help!?

He is 2 and he is VERY very active, lots of energy, loves to play outside. But, if we are not outside he wants to be watching TV. It all started with Barney, he fell in love with that show, now he likes Dora and a couple others. I don't mind turning it on in the mornings while I am feeding my 7 month old and making myself a cup of coffee. But, after that I rather him do something else. I turn off his TV in the playroom and lock the door so he can't go in there and turn it on. And we will read or do a craft. But that doesn't hold his attention for very long before he starts wining about TV again. ANy advice on some other fun activites that a 2 year old would enjoy doing inside the house, that will keep his interest. We are outside a lot during the day...but we can't always be out there because I do have a 7 month old and winter is approaching.