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iOS

Posted by Austin Wyatt
Austin Wyatt
3,146 Points

Touch anywhere on the screen to make an action happen

I am making an app for the blind and I need the user the be aloud to touch anywhere on the screen so that the appropriate action can happen.

1 Answer

Hayden Pennington
Hayden Pennington
6,154 Points
Hayden Pennington
Hayden Pennington
6,154 Points

So, this is actually really easy. You use the UITapGestureRecognizer class. It can be accomplished in Interface Builder, but I prefer to do it in code, plus it will demonstrate how simple it can be done.

I would also like to note that the process is almost identical for other gestures. Like UIPinchGestureRecognizer or UISwipeGestureRecognizer.

I Highly recommend that you read the documentation for UITapGestureRecognizer, to see what all it has to offer.

Anyway, to the code. I usually set up the UITapGestureRecognizer in viewDidLoad, so that is what I will use in my example.

override func viewDidLoad() {
        super.viewDidLoad()

        // First create an instance of UITapGestureRecognizer
        // Specify 'self' for the target, so it will send the instance of UITapGestureRecognizer
        // And specify the method you want to execute for each tap. Note the colon ':' after the method.
        let tapGesture = UITapGestureRecognizer(target: self, action: Selector("handleTapGesture:"))

        // You can set the number of required taps. By default this is 1
        tapGesture.numberOfTapsRequired = 1

        // There are other properties, that you can set too. Like how many fingers have to be touching.

        // Now add the gesture recognizer to your view
        view.addGestureRecognizer(tapGesture)

    }

    // Each tap will call this method
    func handleTapGesture(sender: UITapGestureRecognizer) {
        if sender.state == UIGestureRecognizerState.Ended {
            // Do something...
        }
    }
Austin Wyatt
Austin Wyatt
3,146 Points

How do you connect that with the main storyboard though? How would I connect the code so that when you touch anywhere on the screen a certain action would happen that the user would be able to see?

Austin Wyatt
Austin Wyatt
3,146 Points

How do you connect that with the main storyboard though? How would I connect the code so that when you touch anywhere on the screen a certain action would happen that the user would be able to see?

Austin Wyatt
Austin Wyatt
3,146 Points

How do you connect that with the main storyboard though? How would I connect the code so that when you touch anywhere on the screen a certain action would happen that the user would be able to see?

Austin Wyatt
Austin Wyatt
3,146 Points

How do you connect that with the main storyboard though? How would I connect the code so that when you touch anywhere on the screen a certain action would happen that the user would be able to see?

Hayden Pennington
Hayden Pennington
6,154 Points

A UIViewController in your storyboard has the property 'view'. So, in the line view.addGestureRecognizer(tapGesture), 'view' is referring to the view in your storyboard.

Put a println ( i.e. println("screen touched") ) in 'handleTapGesture', to see if it works.

If your view hierarchy is more complex, you can create an IBOutlet from whichever view, in your storyboard, to your code. And then replace 'view' in view.addGestureRecognizer(tapGesture) with your your the name of your view.