DirectedPinchGestureRecognizer 1.0.0

You want to add pod 'DirectedPinchGestureRecognizer', '~> 1.0' similar to the following to your Podfile:

target 'MyApp' do
  pod 'DirectedPinchGestureRecognizer', '~> 1.0'
end

Then run a pod install inside your terminal, or from CocoaPods.app.

Alternatively to give it a test run, run the command:

pod try DirectedPinchGestureRecognizer

DirectedPinchGestureRecognizer 1.0.0

By
Daniel Clelland

DirectedPinchGestureRecognizer

DirectedPinchGestureRecognizer is a UIPinchGestureRecognizer subclass providing a richer API for working with pinch gestures in Swift 3.

let gestureRecognizer = DirectedPinchGestureRecognizer()
gestureRecognizer.delegate = self
view.addGestureRecognizer(gestureRecognizer)

Installation:

pod 'DirectedPinchGestureRecognizer', '~> 1.0'

Usage:

let gestureRecognizer = DirectedPinchGestureRecognizer()
gestureRecognizer.delegate = self
view.addGestureRecognizer(gestureRecognizer)

Features:

✓ Keeps track of the initial state of the gesture:

if (gestureRecognizer.initialAxis == .horizontal) {
    if (gestureRecognizer.axis == .vertical) {
        print("Gesture recognizer started pinching horizontally and then rotated to a vertical axis")
    }
}

✓ Enforce the gesture’s starting direction and axisx:

func gestureRecognizerShouldBegin(gestureRecognizer: UIGestureRecognizer) -> Bool {
    switch gestureRecognizer {
    case let pinchGestureRecognizer as DirectedPinchGestureRecognizer where pinchGestureRecognizer == self.pinchGestureRecognizer
        return pinchGestureRecognizer.direction == .outwards && pinchGestureRecognizer.axis == .vertical
    default:
        return true
    }
}

✓ Delegate protocol methods for start, update, cancel, and finish events:

func directedPinchGestureRecognizer(didStart gestureRecognizer: DirectedPinchGestureRecognizer) {
    print("Gesture recognizer started")
}

func directedPinchGestureRecognizer(didUpdate gestureRecognizer: DirectedPinchGestureRecognizer) {
    print("Gesture recognizer updated")
}

func directedPinchGestureRecognizer(didCancel gestureRecognizer: DirectedPinchGestureRecognizer) {
    print("Gesture recognizer cancelled")
}

func directedPinchGestureRecognizer(didFinish gestureRecognizer: DirectedPinchGestureRecognizer) {
    print("Gesture recognizer finished")
}

✓ Convenience methods for location, locations, direction, axis, linearScale (scale in points), and geometricScale (scale as a dimensionless unit):

let location = gestureRecognizer.location // CGPoint?
let locations = gestureRecognizer.locations // (CGPoint, CGPoint)?
let direction = gestureRecognizer.direction // DirectedPinchGestureRecognizer.Direction?
let axis = gestureRecognizer.axis // DirectedPinchGestureRecognizer.Axis?
let linearScale = gestureRecognizer.linearScale(inAxis: .vertical, andDirection: .outwards) // CGFloat
let geometricScale = gestureRecognizer.geometricrScale(inAxis: .vertical, andDirection: .outwards) // CGFloat

✓ IBDesignable parameters for enforcing a minimum linear/geometric scale:

gestureRecognizer.minimumLinearScale = 64.0
gestureRecognizer.minimumGeometricScale = 1.0