React native PanResponder interface overview

PanResponder_Overview.js

this._panResponder = PanResponder.create({
  // ----------- NEGOTIATION:
  // A view can become the touch responder by implementing the correct negotiation methods.

    // Should child views be prevented from becoming responder on first touch?
    onStartShouldSetPanResponderCapture: (evt, gestureState) => () => {
      console.info('onStartShouldSetPanResponderCapture');
      return true;
    },

    // Should child views be prevented from becoming responder of subsequent touches?
    onMoveShouldSetPanResponderCapture: (evt, gestureState) => () => {
      console.info('onMoveShouldSetPanResponderCapture');
      return true;
    },

    onShouldBlockNativeResponder: (evt, gestureState) => {
      console.info('onShouldBlockNativeResponder');
      return true;
    },

  // There are two methods to ask the view if it wants to become responder:

    // - Does this view want to become responder on the start of a touch?
    onStartShouldSetPanResponder: (evt, gestureState) => {
      console.info('onStartShouldSetPanResponder', this.isAllowedResponder);
      return this.isAllowedResponder;
    },

    // - Called for every touch move on the View when it is not the responder
    //   does this view want to "claim" touch responsiveness?
    onMoveShouldSetPanResponder: (evt, gestureState) => {
      console.info('onMoveShouldSetPanResponder', this.isAllowedResponder, gestureState);
      return this.isAllowedResponder && gestureState.dx != 0 && gestureState.dy != 0;
    },

  // ... And one when some other view requested to be the responder

    // - Something else wants to become responder.
    //   Should this view release the responder? Returning true allows release
    onPanResponderTerminationRequest: (evt, gestureState) => {
      console.info('onPanResponderTerminationRequest');
      return false;
    },

  // ----------- NEGOTIATION RESULT:
  // If the View returns true and attempts to become the responder,
  // one of the following will happen:

    // - The View is now responding for touch events.
    onPanResponderGrant: (evt, gestureState) => {
      console.info('onPanResponderGrant');
      // This is the time to highlight and show the user what is happening
    },

    // - Something else is the responder right now and will not release it
    onPanResponderReject: (evt) => {
      console.info('onPanResponderReject');
    },

  // ----------- ACTUAL TOUCH HANDLERS:
  // If the view is the responder, the following handlers could be called:

    // - Touch start
    onPanResponderStart: (e) => {
      console.info('onPanResponderStart');
    },

    // - The user is moving their finger
    onPanResponderMove: (e, gestureState) => {
      console.info('onPanResponderMove', dy);
      // React to the movement!
    },

    // - Fired at the end of the touch before onPanResponderRelease
    onPanResponderEnd: (e) => {
      console.info('onPanResponderEnd');
    },

    // - Fired at the end of the touch, ie "touchUp"
    onPanResponderRelease: (e, gestureState) => {
      console.info('onPanResponderRelease');
    },

    // - The responder has been taken from the View.
    //   Might be taken by other views after a call to onPanResponderTerminationRequest,
    //   or might be taken by the OS without asking
    //   (happens with control center/ notification center on iOS)
    onPanResponderTerminate: (evt, gestureState) => {
      console.info('onPanResponderTerminate');
    }
});

From Gesture Responder System + PanResponder

When is isAllowedResponder set to true?

Really helpful, thanks!