问题
How to have navigation bar blurred like on the first image here. I did some research, but seems tint color and translucent does not apply for this needs. I am using iOS 7 and iOS 8
The problem that I have table under navigation bar and it change content dynamically, so the blur effect should be changed as well each time I scroll table.
来源：https://stackoverflow.com/questions/29129845/uinavigationbar-blur-ios-7-1-and-above