Pass Extra Argument for UItapgesturerecognizer with Selector

Pass extra argument for UItapgestureRecognizer with selector

Short answer: no

The selector is called by the UITapGestureRecognizer, and you have no influence on what parameters it passes.

However, what you can do is query the recognizer's view property to get the same information.

func doubleTapComment(recognizer: UIGestureRecognizer) {
    if recognizer.view == label1 {
        ...
    }
    else if recognizer.view == label2 {
        ...
    }
}

Pass Parameter with UITapGestureRecognizer

One approach would be to subclass UITapGestureRecognizer and then set a property, I've posted an example below. You could also do some check on the sender and check if equal to some tag, class, string, e.t.c

class ViewController: UIViewController {

    @IBOutlet weak var label1: UILabel!
    @IBOutlet weak var image: UIImageView!

    override func viewDidLoad() {
        super.viewDidLoad()
        // Do any additional setup after loading the view, typically from a nib.
        image.userInteractionEnabled = true;
        let tappy = MyTapGesture(target: self, action: #selector(self.tapped(_:)))
        image.addGestureRecognizer(tappy)
        tappy.title = "val"
    }

    func tapped(sender : MyTapGesture) {
        print(sender.title)
        label1.text = sender.title
    }
}

class MyTapGesture: UITapGestureRecognizer {
    var title = String()
}

There are lots of examples on SO, have a look, good luck.

How to pass additional parameter to UITapGestureRecognizer?

You can achieve this by creating your own TapGestureRecongnizer class which is the subclass of UITapGestureRecognizer. The example is shown below:

class MyTapGesture: UITapGestureRecognizer {
    var floatValue = 0.0
}

class ViewController: UIViewController {
    override func viewDidLoad() {
        super.viewDidLoad()
        let tapped = MyTapGesture.init(target: self, action: #selector(handleTap))
        tapped.floatValue = 5.0
        tapped.numberOfTapsRequired = 1
        view.addGestureRecognizer(tapped)
    }

    override func didReceiveMemoryWarning() {
        super.didReceiveMemoryWarning()
        // Dispose of any resources that can be recreated.
    }

    func handleTap(recognizer: MyTapGesture) {
        print(recognizer.floatValue)
    }
}

Passing arguments to selector in Swift

It looks like you're misunderstanding a couple of things.

When using target/action, the function signature has to have a certain form…

func doSomething()

or

func doSomething(sender: Any)

or

func doSomething(sender: Any, forEvent event: UIEvent)

where…

The sender parameter is the control object sending the action message.

In your case, the sender is the UITapGestureRecognizer

Also, #selector() should contain the func signature, and does NOT include passed parameters. So for…

func handleTap(sender: UIGestureRecognizer) {
    
}

you should have…

let gesture = UITapGestureRecognizer(target: self, action: #selector(handleTap(sender:)))

Assuming the func and the gesture are within a view controller, of which modelObj is a property / ivar, there's no need to pass it with the gesture recogniser, you can just refer to it in handleTap

Pass on Argument in #selector Swift 2.2

creating a generic UITapGestureRecognizer instead use this:

class CustomTapGestureRecognizer: UITapGestureRecognizer {
    var channelId: String?
}

also use this:

override func viewDidLoad() {
    super.viewDidLoad()

    let gestureRecognizer = CustomTapGestureRecognizer(target: self, action: #selector(tapped(_:))
    gestureRecognizer.channelId = "Your string"
    view1.addGestureRecognizer(gestureRecognizer)
}

func tapped(gestureRecognizer: CustomTapGestureRecognizer) {
    if let channelId = gestureRecognizer.channelId {
        //print
    }
}

Pass multiple parameters to gesture recogniser

You could subclass the gesture recogniser you're using and add the extra variables you want. Example below.

class CustomGestureRecognizer : UITapGestureRecognizer {

    var url : NSURL?
    // any more custom variables here

    init(target: AnyObject?, action: Selector, url : NSURL) {
        super.init(target: target, action: action)

        self.url = url
    }

}

Then when you want to get the url back out.

func didTap(sender : CustomGestureRecognizer) {
    print(sender.url)
}

How to pass an extra parameter

If the function has two parameters like below.

func clicked(sender:AnyObject,value:AnyObject)
{
}

Then

action = "clicked::"

example :

func switchCard(card: Int, withCard card1: Int) 
{
    print(card)
}

let singleTap1 = UITapGestureRecognizer(target: self, action: "switchCard:withCard:")

Just a note on Swift 2.2. You can now type the selector as

#selector(popoverSelectedCode(_:desc:)

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