Overriding an Obj-c class function in Swift

Question

Either I'm seeing some strange behaviour from Swift or I'm doing something wrong.

Let's say you have an obj-c class called TurtleHelper which looks like this:

@interface TurtleHelper : NSObject

+(NSDictionary*)getTurtles;

@end

Then I want to override this method in Swift, so I do this:

class SwiftTurtles: TurtleHelper {

    override class func getTurtles() -> NSDictionary {
        // ...
    }
}

The compiler throws the following error at me:

Overriding method with selector getTurtles has incompatible type () -> NSDictionary

What am I doing wrong?

Answer 1

It turns out that the answer seems to be

override class func getTurtles() -> [NSObject : AnyObject]!

From Apple's documentation:

When you bridge from an NSDictionary object to a Swift dictionary, the resulting dictionary is of type [NSObject: AnyObject]. You can bridge any NSDictionary object to a Swift dictionary because all Objective-C objects are AnyObject compatible.

Reference: https://developer.apple.com/library/prerelease/mac/documentation/Swift/Conceptual/BuildingCocoaApps/WorkingWithCocoaDataTypes.html