In Xcode 6.3 in，We worked Objective-C adds new Null tag Language features。This feature gives a Objective-C language and the same expression Swift empty and non-empty kind of API Interface。Xcode 7 Through the introduction to Objective-C lightweight generic module allows Objective-C and Swif[……]
We all know that in Java declare an abstract class or method you want to use the abstract keyword，But unfortunately familiar things always gone，In Swift has no label。
Then，How should we declare an abstract class it?
Private constructor (initializer) Act
It touches people very familiar, right? Bar private constructor of that class certainly can not be initialized[……]