Swift 4: Timer Crashing - unrecognized selector sent to instance

Question

I\'m trying to call an instance of Timer and print \"A second has passed\" for each second that elapses. I\'m following The Complete iOs 11 & Swift Developer Course on Udemy

Answer 1

The callback function processTimer is not correctly declared:

@objc func processTimer() {
   //your code here
}

You need to add the @objc keyword before the function in order to be called in the Timer callback. Also, in general I think is better to use #selector keyword instead.