Gameplaykit GKState, swift func with two parameters - ios

Question

I'm sure that is a simple question for you.
How can I write a func with two parameters with one GKState?
UPDATE
Apple use
func willExitWithNextState(_ nextState: GKState)
If I use somefunc(state:GKState) works fine
while somefunc(state:GKState, string:String) does't work, why???
Other example
I've tried this:
class Pippo:GKState {}
//1
func printState (state: GKState?) {
print(state)
}
printState(Pippo) //Error cannot convert value of type '(Pippo).Type' (aka 'Pippo.Type') to expected argument type 'GKState?'
//2
func printStateAny (state: AnyClass?) {
print(state)
}
printStateAny(Pippo) //NO Error
//3
func printStateGeneral <T>(state: T?) {
print(state)
}
printStateGeneral(Pippo) //No Error
//4
func printStateAnyAndString (state: AnyClass?, string:String) {
print(state)
print(string)
}
printStateAnyAndString(Pippo/*ExpectedName Or costructor*/, string: "Hello") //ERROR
printStateAnyAndString(Pippo()/*ExpectedName Or costructor*/, string: "Hello") //ERROR cannot convert value of type 'Pippo' to expected argument type 'AnyClass?'
SOLUTION THANKS #0x141E
func printStateAnyAndString (state: GKState.Type, string:String) {
switch state {
case is Pippo.Type:
print("pippo")
default:
print(string)
}
}
printStateAnyAndString(Pippo.self, string: "Not Pippo")
Thanks for reply

Answer 1

If you want a parameter to be a class, use Class.Type or AnyClass
func printState (state: AnyClass, string:String) {
print(state)
print(string)
}
and use Class.self as the argument
printState(Pippo.self, string:"hello pippo")
Update
If your function definition is
func printState (state:GKState, string:String) {
if state.isValidNextState(state.dynamicType) {
print("\(state.dynamicType) is valid")
}
print(state)
print(string)
}
you'll need to pass in an instance of GKState (or a subclass of GKState) as the first argument, not the class/subclass itself. For example,
let pippo = Pippo()
printState (pippo, "Hello")

Answer 2

Throughout your sample code you have used AnyClass, whereas you should (probably) be using AnyObject. AnyClass refers to a class definition, whereas AnyObject is an instance of a class.
class MyClass { }
func myFunc1(class: AnyClass)
func myFunc2(object: AnyObject)
let myObject = MyClass() // create instance of class
myFunc1(MyClass) // myFunc1 is called with a class
myFunc2(myObject) // myFunc2 is called with an instance
You have also made most of your parameters Optionals with the "?", whereas it doesn't look required. For example:
printState(nil) // What should this do?