Repeat function using NSTimer fails with target: self in Swift

Question

I found this question and tried to copy the code to my Xcode project, but I'm getting the following error message.

error: use of unresolved identifier 'self'

What's the right way?

EDIT: Here the code, tested in a playground:

    //: Playground - noun: a place where people can play

import Cocoa
import Foundation

func sayHello() {
    print("hello World")
}

var SwiftTimer = NSTimer()
SwiftTimer = NSTimer.scheduledTimerWithTimeInterval(1, target:self, selector: Selector("sayHello"), userInfo: nil, repeats: true)

Answer 1

Usually using uppercase to the properties name it's considered as a bad attitude, you should use swiftTimer.

These expressions are not allowed ad the top level:

var swiftTimer = NSTimer()
swiftTimer = NSTimer.scheduledTimerWithTimeInterval(1, target:self, selector: Selector("sayHello"), userInfo: nil, repeats: true)

You must put it in a function like for example:

override func viewDidLoad() {
        super.viewDidLoad()
        var swiftTimer = NSTimer()
        swiftTimer = NSTimer.scheduledTimerWithTimeInterval(1, target:self, selector: Selector("sayHello"), userInfo: nil, repeats: true)
}