Apple-Cranberry Casserole

How could I forget about this one?  I used to make it a lot.  This one comes from my Junaluska Joy cookbook,  copyright 1982.

Combine the first four ingredients and spread into a buttered oblong baking dish.

3 cups chopped, unpeeled apples
2 cups whole cranberries
1 1/4 cups sugar
1/2 cup all purpose flour

Combine and sprinkle the following over the fruit mixture:

1/2 cup melted butter
1 1/2 cups oatmeal, uncooked
1/2 cup brown sugar
1/2 chopped nuts

Bake 1 hour at 350 degrees.