An iBooks style book shelf
Features:
- drag & drop
- scroll up/down while draging
- add & remove animation
- custom header (add a search bar or anything you want)
TODO:
- does not support orientation change now, it's fixed Portrait or landscape (doesn't have a convenient method to reload the parameters in the init method.)
- the init method need too many parameters now. I will move all of them to GSBookShelfViewDataSource protocol methods, and this will help a lot when orientation changes, but maybe there'll be too many protocol methods.