Gestures are like a higher-level abstraction than the Layer touch handler API. For instance, a PanGesture consumes a series of touch events but does not actually begin until the user moves a certain distance with a specified number of fingers. Gestures can also be exclusive: by default, if a gesture recognizes, traditional touch handlers for that subtree will be cancelled. You can control this with the cancelsTouchesInView argument to Gesture initializers (see docs for individual gestures for more details).

Also by default, if one gesture recognizes, it will prevent all other gestures involved in that touch from recognizing. For instance, if you attach both a PanGesture and a PinchGesture to a layer, and the pinch gesture recognizes, then the pan gesture will not also try to recognize. You can control this with the shouldRecognizeSimultaneouslyWithGesture property (see docs for individual gestures for more details).

You don’t make a Gesture directly–you always make some kind of gesture. See PanGesture, TapGesture, PinchGesture, RotationGesture to learn more.

layer.gestures = [
	TapGesture { location in println("Tapped at \(location)") }
layer.gestures = [
	new TapGesture({handler: function(location) {
		console.log("Tapped at " + location)

Continuous vs. discrete gestures

Continuous gestures are different from discrete gestures in that they pass through several phases. A discrete gesture simply recognizes–then it’s done. A continuous gesture begins, then may change over the course of several events, then ends (or is cancelled). Continuous gestures will pass their current phase (a ContinuousGesturePhase; see below) to their handlers.

Method reference

  • public enum ContinuousGesturePhase{}ContinuousGesturePhase

    ContinuousGesturePhase is an enum specifying a phase of continuous gesture recognition (see above).

    When a gesture has just recognized, it will invoke its handler with phase Began. Then it will repeatedly invoke the handler with Changed until finally invoking it with either Ended or Cancelled.

    ContinuousGesturePhase has the following fields:

    public enum ContinuousGesturePhase {
        case Began
        case Changed
        case Ended
        case Cancelled