Double tap gesture function is being fired after 1 tap only on first tap, every other instance it requires 2 taps

Question

As of right now, when I run my program and tap, I am getting the println() message after one tap. However, after the first println() message, I have to double tap for every following println() message.

I want it so every time I have to double tap (including the first time).

In my View Controller I have the following:

@IBOutlet weak var graphview: GraphView! {
    didSet {
        //
        graphview.addGestureRecognizer(UITapGestureRecognizer(target: graphview, action: "doubleTap:"))
    }
}

And my function in the View is the following:

func doubleTap(gesture: UITapGestureRecognizer)
{
    gesture.numberOfTapsRequired = 2
    println("hit twice")

}

Answer 1

You have to set

gesture.numberOfTapsRequired = 2

before adding the gesture recognizer to the view, i.e.

@IBOutlet weak var graphview: GraphView! {
    didSet {
        var doubleTap: UITapGestureRecognizer = UITapGestureRecognizer(target: graphview, action: "doubleTap:")
        doubleTap.numberOfTapsRequired = 2
        graphview.addGestureRecognizer(doubleTap)
    }
}

and

func doubleTap(gesture: UITapGestureRecognizer)
{
    println("hit twice")
}