I made this bag last night. It is cute, but it has some design flaws that I need to correct in my pattern. I wanted a very rectangular bag, but with this type of purse, I need the sides to angle a bit so they don't gap open when the flap is shut. I plan on making the adjustments to the pattern. Also, flannel is not the best material to line a bag with because it is too soft. If I use flannel again, I will have to reinforce it.
The outer is cotton fabric with fused/sewn interfacing, the lining is flannel with a divided pocket, and the strap is nylon. When I fix my pattern and sew another bag, I'll post the results.