PanResponder React本机参数

Question

I have a problem with panResponder My code :

componentWillMount() {
    this._panResponder = PanResponder.create({
      onStartShouldSetPanResponder: (evt, gestureState) => false,
      onStartShouldSetPanResponderCapture: (evt, gestureState) => true,
      onMoveShouldSetPanResponder: (evt, gestureState) => Math.abs(gestureState.dy) > 5,
      onMoveShouldSetPanResponderCapture: (evt, gestureState) => true,
      onPanResponderMove: this._handlePanResponderMove,
    });
  }

_handlePanResponderMove(event, gestureState) {
    if (gestureState.dy > current) {
      console.log("Down");
    } else {
      console.log("Up");
    }
    current = gestureState.dy;
  }

componentTag() {
   return tabTag.map((item, id) => {
      return(
        <View key={id} >
            <View {...this._panResponder.panHandlers}>
                <Icon name="ios-reorder" ></Icon>
            </View>
        </View>
      );
    });
}

render() {
   return (
     {this.componentTag}
   );
}

I would like to know when i am in the function _handlePanResponderMove the value of id of my array but i can't give parameters to the function

Answer 1

The event parameter in handlePanResponderMove Give you node id of the target of the touch. Ie Event.nativeEvent.target can help you with this.

Answer 2

Inside your componentTag you're using this keyword, to do that, you'll need to bind this to your method.

You need a constructor like following:

constructor() {
   this.componentTag = this.componentTag.bind(this);

   //since you're using this keyword on componentDidMount as well,
   this.componentWillMount = this.componentWillMount.bind(this);
}