Instance Property

force

The force of the touch, where a value of 1.0 represents the force of an average touch (predetermined by the system, not user-specific).

Declaration

var force: CGFloat { get }

Discussion

This property is available on devices that support 3D Touch or Apple Pencil. To check at runtime if a device supports 3D Touch, read the value of the forceTouchCapability property on the trait collection for any object in your app with a trait environment.

Note that the force reported by Apple Pencil is measured along the axis of the pencil. If you want a force perpendicular to the device, you need to calculate this value using the altitudeAngle value.

See Also

Getting Touch Attributes

var tapCount: Int

The number of times the finger was tapped for this given touch.

var timestamp: TimeInterval

The time when the touch occurred or when it was last mutated.

var type: UITouchType

The type of the touch.

var phase: UITouchPhase

The phase of the touch.

var maximumPossibleForce: CGFloat

The maximum possible force for a touch.

var altitudeAngle: CGFloat

The altitude (in radians) of the stylus.

func azimuthAngle(in: UIView?)

Returns the azimuth angle (in radians) of the stylus.

func azimuthUnitVector(in: UIView?)

Returns a unit vector that points in the direction of the azimuth of the stylus.