Setting target method of a button to a function from another class

Question

I have a function that fetches photos info from facebook. I try to abstract it by adding it to another class and setting target function of the button to that class function.

So I have a singleton class

class FacebookManager  {



static let sharedInstance = FacebookManager()



func getAlbums() {



    var request: FBSDKGraphRequest = FBSDKGraphRequest.init(graphPath: "/\(facebookID!)/albums", parameters: ["fields": "cover_photo, name, description"])

    request.startWithCompletionHandler({ (connection, result, error) -> Void in

        // do stuff

    })



}

and a method in viewcontroller for button that calls that function

dummyButton?.addTarget(FacebookManager.self, action: Selector("getAlbums"), forControlEvents: .TouchUpInside)

but after tapping on button I get an error

2016-08-17 00:12:21.599 Lovrr[11807:3832289] *** NSForwarding: warning: object 0x10717c888 of class 'app.FacebookManager' does not implement methodSignatureForSelector: -- trouble ahead
Unrecognized selector +[app.FacebookManager getAlbums]

in some topic in stackoverflow I saw an advice of subclassing

NSObject

in FacebookManager. After doing this I get another error

[app.FacebookManager getAlbums]: unrecognized selector sent to class 0x1047026f0
2016-08-17 00:13:49.469 app[11892:3834005] *** Terminating app due to uncaught exception 'NSInvalidArgumentException', reason: '+[app.FacebookManager getAlbums]: unrecognized selector sent to class 0x1047026f0'

How to do what I want properly ?

Answer 1

Your target is wrong:

dummyButton?.addTarget(FacebookManager.self, action: Selector("getAlbums"), forControlEvents: .TouchUpInside)

FacebookManager.self is static. getAlbums is a class method. => unrecognized selector

Try to change:

dummyButton?.addTarget(FacebookManager.sharedInstance, action: Selector("getAlbums"), forControlEvents: .TouchUpInside)

Setting target method of a button to a function from another class

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