getInteractionHandle(): ?number {
        return interactionState.handle;
      }
@param {object} config Enhanced versions of all of the responder callbacks
that provide not only the typical `ResponderSyntheticEvent`, but also the
`PanResponder` gesture state.  Simply replace the word `Responder` with
`PanResponder` in each of the typical `onResponder*` callbacks. For
example, the `config` object would look like:

 - `onMoveShouldSetPanResponder: (e, gestureState) => {...}`
 - `onMoveShouldSetPanResponderCapture: (e, gestureState) => {...}`
 - `onStartShouldSetPanResponder: (e, gestureState) => {...}`
 - `onStartShouldSetPanResponderCapture: (e, gestureState) => {...}`
 - `onPanResponderReject: (e, gestureState) => {...}`
 - `onPanResponderGrant: (e, gestureState) => {...}`
 - `onPanResponderStart: (e, gestureState) => {...}`
 - `onPanResponderEnd: (e, gestureState) => {...}`
 - `onPanResponderRelease: (e, gestureState) => {...}`
 - `onPanResponderMove: (e, gestureState) => {...}`
 - `onPanResponderTerminate: (e, gestureState) => {...}`
 - `onPanResponderTerminationRequest: (e, gestureState) => {...}`
 - `onShouldBlockNativeResponder: (e, gestureState) => {...}`

 In general, for events that have capture equivalents, we update the
 gestureState once in the capture phase and can use it in the bubble phase
 as well.

 Be careful with onStartShould* callbacks. They only reflect updated
 `gestureState` for start/end events that bubble/capture to the Node.
 Once the node is the responder, you can rely on every start/end event
 being processed by the gesture and `gestureState` being updated
 accordingly. (numberActiveTouches) may not be totally accurate unless you
 are the responder.