ForceTouchGestureHandler (iOS only)

danger

Consider using the new gestures API instead. The old API is not actively supported and is not receiving the new features. Check out RNGH 2.0 section in Introduction for more information.

A continuous gesture handler that recognizes force of a touch. It allows for tracking pressure of touch on some iOS devices. The handler activates when pressure of touch if greater or equal than minForce. It fails if pressure is greater than maxForce Gesture callback can be used for continuous tracking of the touch pressure. It provides information for one finger (the first one).

At the beginning of the gesture, the pressure factor is 0.0. As the pressure increases, the pressure factor increases proportionally. The maximum pressure is 1.0.

The handler is implemented using custom UIGestureRecognizer on iOS. There's no implementation provided on Android and it simply render children without any wrappers. Since this behaviour is only provided on some iOS devices, this handler should not be used for defining any crucial behaviors. Use it only as an additional improvement and make all features to be accessed without this handler as well.

Properties

See set of properties inherited from base handler class. Below is a list of properties specific to ForceTouchGestureHandler component:

minForce

A minimal pressure that is required before handler can activate. Should be a value from range [0.0, 1.0]. Default is 0.2.

maxForce

A maximal pressure that could be applied for handler. If the pressure is greater, handler fails. Should be a value from range [0.0, 1.0].

feedbackOnActivation

Boolean value defining if haptic feedback has to be performed on activation.

Event data

See set of event attributes from base handler class. Below is a list of gesture event attributes specific to ForceTouchGestureHandler:

force

The pressure of a touch.

Static method

forceTouchAvailable

You may check if it's possible to use ForceTouchGestureHandler with ForceTouchGestureHandler.forceTouchAvailable

Example

See the force touch handler example from Gesture Handler Example App.

<ForceTouchGestureHandler
  minForce={0}
  onGestureEvent={this._onGestureEvent}
  onHandlerStateChange={this._onHandlerStateChange}>
  <Animated.View
    style={[
      styles.box,
      { transform: [{ scale: Animated.add(1, this.force) }] },
    ]}
  />
</ForceTouchGestureHandler>