与Objective-C中的Java ArrayList等效

Question

In Objective-C what is equivalent of List<Products> cartProduct = new ArrayList(); . I used NSMutableArray but that is different than Java ArrayList.

Answer 1

It sounds to me like Java ArrayLists use generics.

Objective-C does not have true support for generics. (Swift does. You may want to use Swift instead.)

Objective-C's collection classes ( NSArray and NSMutableArray ) are heterogeneous. They can contain a mixture of objects of different types. However, a recent addition to the language adds a very thin layer of generic support.

You'd use syntax like this:

NSMutableArray <Products *> *cartProduct;

That syntax only adds compile-time type checking. It tells the compiler that cartProduct is a mutable array that should only contain objects of type Products , so you get warnings when you to add/fetch objects of other types from the array, but the array will still take objects of any type at runtime.

I found this link explaining more about Objective-C's "lightweight" support for generics. It seems pretty clear and well written.