UISwipeGestureRecognizer has a direction property that has the following definition:
var direction: UISwipeGestureRecognizerDirection
The permitted direction of the swipe for this gesture recognizer.
The problem with Swift 3.0.1 (and below) is that even if UISwipeGestureRecognizerDirection conforms to OptionSet, the following snippet will compile but won't produce any positive expected result:
// This compiles but does not work
let gesture = UISwipeGestureRecognizer(target: self, action: #selector(gestureHandler))
gesture.direction = [.right, .left, .up, .down]
self.addGestureRecognizer(gesture)
As a workaround, you will have to create a UISwipeGestureRecognizer for each desired direction.
The following Playground code shows how to implement several UISwipeGestureRecognizer for the same UIView and the same selector using Array's map method:
import UIKit
import PlaygroundSupport
class SwipeableView: UIView {
convenience init() {
self.init(frame: CGRect(x: 100, y: 100, width: 100, height: 100))
backgroundColor = .red
[UISwipeGestureRecognizerDirection.right, .left, .up, .down].map({
let gesture = UISwipeGestureRecognizer(target: self, action: #selector(gestureHandler))
gesture.direction = $0
self.addGestureRecognizer(gesture)
})
}
func gestureHandler(sender: UISwipeGestureRecognizer) {
switch sender.direction {
case [.left]: frame.origin.x -= 10
case [.right]: frame.origin.x += 10
case [.up]: frame.origin.y -= 10
case [.down]: frame.origin.y += 10
default: break
}
}
}
class ViewController: UIViewController {
override func viewDidLoad() {
super.viewDidLoad()
view.backgroundColor = .white
view.addSubview(SwipeableView())
}
}
let controller = ViewController()
PlaygroundPage.current.liveView = controller