About UITapGestrueRecognizer in Swift - swift

I have made a view subclass of UIView.Then, I added UITapGestureRecognizer to it but when I tap on the view, it don't respond to it.
Code:
let tapGesture = UITapGestureRecognizer(target: self, action: "singleTapHandler:")
self.maskView!.addGestureRecognizer(tapGesture)
selector:
func singleTapHandler(recognizer: UITapGestureRecognizer) {
print("xxx")
dismiss()
}

Ensure that you have enabled user interactivity:
self.maskView!.userInteractionEnabled = true

Make sure the maskView on top of the view, and the frame not equals to CGRectZero

Check if you added UIGestureRecognizerDelegate to your view, and use that tapGesture.delegate = self
Your tapGesture should be like let tapGesture = UITapGestureRecognizer(target: self, action: "singleTapHandler"), there is no need of :
Then your function can
func singleTapHandler(){
//action
}
Lastly, make sure you tap on the view you added the tap gesture.

Related

How to single out and action a UITapGestureRecognizer for a UIView that is in the UIViewController.view that also has a UITapGestureRecognizer?

I have a UIView object that I have added a UITapGestureRecognizer. The main view also has a UITapGestureRecognizer that i use to hide the keyboard. How can i prioritise the tapGesture on the child UIView to do what i need to do? I would like, when tapping the child view to trigger the action associated with this tap, rather than the main views's gesture.
I have tried adding a double tap to the child view, to distinguish between the two gestures, but this just triggers the action for the main views's tap action.
var childView: UIView!
/**Tap screen event listener - to hide the keyboard*/
let tapGesture = UITapGestureRecognizer.init(target: self, action: #selector(hideKeyBaord))
self.view.addGestureRecognizer(tapGesture)
let doubleTap = UITapGestureRecognizer.init(target: self, action: #selector(doSomethingElse))
doubleTap.numberOfTouchesRequired = 2
childView.view.addGestureRecognizer(doubleTap)
One way is to implement the shouldReceiveTouch delegate method for tapGesture:
extension YourViewController : UIGestureRecognizerDelegate {
override func gestureRecognizer(_ gestureRecognizer: UIGestureRecognizer, shouldReceive touch: UITouch) -> Bool {
if gestureRecogniser == tapGesture {
// tapGesture should not receive the touch when the touch is inside the child view
let location = touch.location(in: childView)
return !childView.bounds.contains(location)
} else {
return true
}
}
}
And remember to set the delegate of tapGesture to self.

Tap Gesture isn't working. User interaction enabled.

Have following view structure:
Programmatically adding tap gesture rec to Temp lbl:
let tempLblTap: UITapGestureRecognizer = UITapGestureRecognizer(target: self, action: #selector(MainFeedVC.convertDegrees))
tempLblTap.delegate = self
tempLblTap.numberOfTapsRequired = 1
tempLblTap.numberOfTouchesRequired = 1
tempLblTap.cancelsTouchesInView = false
self.tempLbl.isUserInteractionEnabled = true
self.tempLbl.addGestureRecognizer(tempLblTap)
but the method convertDegrees isn't triggered.
There are also 2 swipe gesture recognizers that are added to the same view:
let leftSwipeGestureRecognizer: UISwipeGestureRecognizer = UISwipeGestureRecognizer(target: self, action: #selector(MainFeedVC.showPostPicVC))
leftSwipeGestureRecognizer.direction = UISwipeGestureRecognizerDirection.left
self.view.addGestureRecognizer(leftSwipeGestureRecognizer)
let rightSwipeGestureRecognizer: UISwipeGestureRecognizer = UISwipeGestureRecognizer(target: self, action: #selector(MainFeedVC.showUserVC))
rightSwipeGestureRecognizer.direction = UISwipeGestureRecognizerDirection.right
self.view.addGestureRecognizer(rightSwipeGestureRecognizer)
Maybe they are the reason?
Found solution:
View that contained my lbl had its userInteractionEnabled unchecked in storyboards.
So, when adding gesture recognizers to labels, images or simply adding buttons, always check that all parent views has its userInteractionEnabled to true.

Display menu list on Double Tap gesture - Swift3

I'm new to IOS and I'm trying to display list of buttons on double tap of UIView. I have the below code to capture the double tap gesture:
let menuTap = UITapGestureRecognizer(target: self, action: #selector(showMenuPanel(_:)))
menuTap.minimumPressDuration = 0.0
menuTap.numberOfTapsRequired = 2
menuTap.delaysTouchesBegan = true
self.view.isUserInteractionEnabled = true
self.view!.addGestureRecognizer(menuTap)
func showMenuPanel(_ recognizer: UITapGestureRecognizer) {
print("TESTPANEL")
}
I need to design a panel to show a list of buttons such as start, stop and pause. Can anybody guide me on how to design a panel on the tapped position?
You need to use UITapGestureRecognizer for that not the UILongPressGestureRecognizer. Set UITapGestureRecognizer with numberOfTapsRequired to 2.
let menuTap = UITapGestureRecognizer(target: self, action: #selector(showMenuPanel(_:)))
menuTap.numberOfTapsRequired = 2
//No need to set isUserInteractionEnabled to true because by default it is true for `UIView`
//self.view.isUserInteractionEnabled = true
self.view!.addGestureRecognizer(menuTap)
Add action method of tapGesture like this.
func showMenuPanel(_ recognizer: UITapGestureRecognizer) {
print("TESTPANEL")
let point = recognizer.location(in: self.view)
//Get your view from nib
let view = CustomView()
//set its origin to this point
view.frame.origin = point
//add your view in self.view
self.view.addSubview(view)
}

Swift: Re-activating Tap Gesture on Disclosure Indicators

I have a Swift project that has a Table View Controller with multiple Static Cell Sections. Some cells have UITextFields and others have Accessory: Disclosure Indicators. I’ve implemented the following Swift code to dismiss the keyboard when the background is tapped:
override func viewDidLoad() {
super.viewDidLoad()
let tapGesture = UITapGestureRecognizer(target: self, action: Selector("hideKeyboard"))
tapGesture.cancelsTouchesInView = true
tableView.addGestureRecognizer(tapGesture)
}
func hideKeyboard() {
tableView.endEditing(true)
}
This works great for releasing the keyboard on tapping the background, but it also removed the tap gesture for the Disclosure Indicators (swipe still works). Does anyone know how to re-activate the tap gesture for the Disclosure Indicators cells after implementing this hideKeyboard() function?
Keep a reference to the gesture recognizer and remove it from the view when you hide the keyboard.
class YourController: UITableViewController {
let tapGesture: UITapGestureRecognizer = {
let tg = UITapGestureRecognizer(target: self, action: "hideKeyboard")
tg.cancelsTouchesInView = true
return tg
}()
override func viewDidLoad() {
super.viewDidLoad()
tableView.addGestureRecognizer(tapGesture)
}
func hideKeyboard() {
tableView.endEditing(true)
tableView.removeGestureRecognizer(tapGesture)
}
}

How do I implement a UIGestureRecognizer in my app in Swift?

Lets say I have an image of a tree and when I tap on the screen it changes to an image of a car how would I do this? This is the code I have so far but its not working. (I have three images named "gp1", "gp2", and "gp3" and all of them have different number of taps to change the image.)
I'm in Spritekit and using Swift.
class GameScene: SKScene, SKPhysicsContactDelegate {
//Create Touch
createTouch()
}
override func didMoveToView(view: SKView) {
func createTouch() {
gestureRecognizer.numberOfTapsRequired = 1
gestureRecognizer2.numberOfTapsRequired = 2
gestureRecognizer3.numberOfTapsRequired = 3
gestureRecognizer == UITapGestureRecognizer(target: self, action: "gp2")
gestureRecognizer2 == UITapGestureRecognizer(target: self, action: "gp3")
gestureRecognizer3 == UITapGestureRecognizer(target: self, action: "gp1")
}
}
As Mundi said, for each UIImageView, make sure userInteractionEnabled = true. Otherwise, users won't be able to tap the image. Then, create the gestureRecognizer. Set the action to the method that will handle the gesture. Next, add the gestureRecognizer to the UIImageView. Finally, write the method to handle the gesture.
#IBOutlet var gp1: UIImageView!
#IBOutlet var gp2: UIImageView!
#IBOutlet var gp3: UIImageView!
func createTouch() {
// maker sure userInteractionEnabled is true
gp1.userInteractionEnabled = true;
gp2.userInteractionEnabled = true;
gp3.userInteractionEnabled = true;
// create the gesture recognizers
let gestureRecognizer1 = UITapGestureRecognizer(target: self, action: "tapGesture:")
let gestureRecognizer2 = UITapGestureRecognizer(target: self, action: "tapGesture:")
let gestureRecognizer3 = UITapGestureRecognizer(target: self, action: "tapGesture:")
// set the number of taps
gestureRecognizer1.numberOfTapsRequired = 1
gestureRecognizer2.numberOfTapsRequired = 2
gestureRecognizer3.numberOfTapsRequired = 3
// add the gesture recognizer to the UIImageViews
gp1.addGestureRecognizer(gestureRecognizer1)
gp2.addGestureRecognizer(gestureRecognizer2)
gp3.addGestureRecognizer(gestureRecognizer3)
}
Since these are all tap gestures, I've decided to use one method and a switch statement. You could, however, create different methods for each gesture if you wanted to.
func tapGesture(gesture: UITapGestureRecognizer) {
switch gesture.numberOfTapsRequired {
case 1:
gp1.image = UIImage(named: "car")
case 2:
gp2.image = UIImage(named: "car")
case 3:
gp3.image = UIImage(named: "car")
default:
break
}
}
You need to add the recognizer to the view and implement the action handlers gp2 etc.
For UIImageView you should also make sure userInteractionEnabled is set to true.