Function components can not be given refs. Attempts to access this ref will fail

Console Warning
Function components cannot be given refs. Attempts
to access this ref will fail. Did you mean to use
React.forwardRef()?
Check the render method of ‘OnboardingScreen’
Warning: Function components cannot be given refs.
Attempts to access this ref will fail. Did you mean to
use React.forwardRef()?%s%S
Check the render method of ‘OnboardingScreen*

I get this warning and I can’t transmit Ref

OnboardingScreen

import React, {useRef, useState} from 'react';
import {Dimensions, View} from 'react-native';
import {ONBOARDING} from '../data/onboarding';
import Onboarding from '../components/ Onboarding/Onboarding';
import OnboardingFooter from '../components/ Onboarding/OnboardingFooter';
import {colors} from '../constants/config';

const windowWidth = Dimensions.get('window').width;
const OnboardingScreen = () => {
  const [currentSate, setCurrentState] = useState(0);
  const ref = useRef(null);
  const updateCurrentState = e => {
    const contentOffsetX = e.nativeEvent.contentOffset.x;
    const currentSate = Math.round(contentOffsetX / windowWidth);
    setCurrentState(currentSate);
  };
  const nextSlider = () => {
    const nextSliderState = currentSate + 1;
    if (nextSliderState != ONBOARDING.length) {
      const offset = nextSliderState * windowWidth;
      ref?.current?.scrollToOffset({offset});
      setCurrentState(nextSliderState);
    }
  };
  return (
    <View style={{flex: 1, backgroundColor: colors.lightGray}}>
      <Onboarding
        list={ONBOARDING}
        updateCurrentState={updateCurrentState}
        ref={ref}
      />
      <OnboardingFooter
        list={ONBOARDING}
        currentSate={currentSate}
        nextSlider={nextSlider}
      />
    </View>
  );
};

export default OnboardingScreen;

Onboarding

import React from 'react';
import {Dimensions, FlatList, Image, Text, View} from 'react-native';

const windowWidth = Dimensions.get('window').width;
const windowHeight = Dimensions.get('window').height;
const Onboarding = ({list, updateCurrentState, ref}) => {
  return (
    <FlatList
      data={list}
      horizontal
      ref={ref}
      pagingEnabled
      onMomentumScrollEnd={updateCurrentState}
      contentContainerStyle={{height: windowHeight * 0.75}}
      showsHorizontalScrollIndicator={false}
      renderItem={({item, index}) => {
        return (
          <View style={{alignItems: 'center'}}>
            <Image
              source={item.image}
              style={{height: '75%', width: windowWidth}}
            />
            <Text
              style={{
                color: 'white',
                fontSize: 22,
                fontWeight: 'bold',
                marginTop: 30,
              }}>
              {item.title}
            </Text>
            <Text
              style={{
                color: 'white',
                fontSize: 13,
                marginTop: 5,
                maxWidth: '80%',
                textAlign: 'center',
                lineHeight: 23,
              }}>
              {item.subtitle}
            </Text>
          </View>
        );
      }}
    />
  );
};

export default Onboarding;


>Solution :

You need to follow forwarding ref, refer to this doc: https://reactjs.org/docs/forwarding-refs.html

Your solution is as below:

import React, {useRef, useState} from 'react';
import {Dimensions, View} from 'react-native';
import {ONBOARDING} from '../data/onboarding';
import Onboarding from '../components/ Onboarding/Onboarding';
import OnboardingFooter from '../components/ Onboarding/OnboardingFooter';
import {colors} from '../constants/config';

const windowWidth = Dimensions.get('window').width;
const OnboardingScreen = () => {
  const [currentSate, setCurrentState] = useState(0);

  const ref = React.createRef(null); //<-----------change here

  const updateCurrentState = e => {
    const contentOffsetX = e.nativeEvent.contentOffset.x;
    const currentSate = Math.round(contentOffsetX / windowWidth);
    setCurrentState(currentSate);
  };
  const nextSlider = () => {
    const nextSliderState = currentSate + 1;
    if (nextSliderState != ONBOARDING.length) {
      const offset = nextSliderState * windowWidth;
      ref?.current?.scrollToOffset({offset});
      setCurrentState(nextSliderState);
    }
  };
  return (
    <View style={{flex: 1, backgroundColor: colors.lightGray}}>
      <Onboarding
        list={ONBOARDING}
        updateCurrentState={updateCurrentState}
        ref={ref}
      />
      <OnboardingFooter
        list={ONBOARDING}
        currentSate={currentSate}
        nextSlider={nextSlider}
      />
    </View>
  );
};

export default OnboardingScreen;

Onboarding

import React from 'react';
import {Dimensions, FlatList, Image, Text, View} from 'react-native';

const windowWidth = Dimensions.get('window').width;
const windowHeight = Dimensions.get('window').height;
const Onboarding = React.forwardRef(({list, updateCurrentState},ref) => {   //<====================here
  return (
    <FlatList
      data={list}
      horizontal
      ref={ref}
      pagingEnabled
      onMomentumScrollEnd={updateCurrentState}
      contentContainerStyle={{height: windowHeight * 0.75}}
      showsHorizontalScrollIndicator={false}
      renderItem={({item, index}) => {
        return (
          <View style={{alignItems: 'center'}}>
            <Image
              source={item.image}
              style={{height: '75%', width: windowWidth}}
            />
            <Text
              style={{
                color: 'white',
                fontSize: 22,
                fontWeight: 'bold',
                marginTop: 30,
              }}>
              {item.title}
            </Text>
            <Text
              style={{
                color: 'white',
                fontSize: 13,
                marginTop: 5,
                maxWidth: '80%',
                textAlign: 'center',
                lineHeight: 23,
              }}>
              {item.subtitle}
            </Text>
          </View>
        );
      }}
    />
  );
});       //<============here

export default Onboarding;

Leave a Reply