JDFPeekaboo能够帮助实现在往下滚动列表的时候能够藏起navigation bar，这是一种很常用的需求，相信可以帮助很多同学。
it's very easy to use. Simply add a property for it:
@property (nonatomic, strong) JDFPeekabooCoordinator *scrollCoordinator;
Then, set it up (say, in-viewDidLoad):
self.scrollCoordinator = [[JDFPeekabooCoordinator alloc] init];self.scrollCoordinator.scrollView = self.scrollView;self.scrollCoordinator.topView = self.navigationController.navigationBar;self.scrollCoordinator.bottomView = self.navigationController.toolbar;
项目主页：http://www.open-open.com/lib/view/home/1429107357814
