Stateless function components cannot hav refs

Question

I'm building search page similar to Facebook or instagram. Basically if we press search button, it navigates to 'SearchScreen'. When its component is mounted, I want to set the search header is focused (cursor).

My problem is when I set TextInput ref as a prop. And I'm getting Stateless function components cannot have refs error. Is this right approach? Why is it not working? Do you know any better approach other than this?

I added _renderHeader private function to renderHeader props in FlatList. This is _renderHeader

  _renderHeader = () => {
    return (
      <View style={styles.layoutheader}>
        <View style={styles.containerheader}>
          <RkTextInput
            rkType='row'
            ref="sbar"  /////////////////////HERE////////////
            autoCapitalize='none'
            autoCorrect={false}
            label={<RkText rkType='awesome' style={{color:'white'}}>{FontAwesome.search}</RkText>}
            placeholder='Search'
            underlineWidth="1"
            underlineColor="white"
            style={styles.searchBarheader}
            inputStyle={{color:'white'}}
            labelStyle={{marginRight:0}}
            value={this.state.inputText}
            onChangeText={(inputText)=>{this.setState({inputText})}}
          />
          <View style={styles.left}>
            <RkButton
              rkType='clear'
              style={styles.menuheader}
              onPress={() => {
                this.props.navigation.goBack()
              }}>
              <RkText style={styles.titleText} rkType='awesome hero'>{FontAwesome.chevronLeft}</RkText>
            </RkButton>
          </View>
        </View>
      </View>
    )
  }

componentDidMount() {
    this.refs.sbar.focus(); ////////// Here I want to focus RkTextInput when it's loaded
}

UPDATE here is actual code as requested

class SearchScreen extends Component {
  static navigationOptions = ({navigation}) => ({
    header: null
  })

  state = {
    active: false,
    inputText: ''
  }
   ...
  _renderRow = (row) => {
    ...
    );
  }

  _renderHeader = () => {
    ...
  }

  render() {
    return (
      <FlatList
        data={null}
        renderItem={this._renderRow}
        renderHeader={this._renderHeader}
        keyExtractor={this._keyExtractor}
        ListHeaderComponent={this._renderHeader}
      />
    );
  }

  componentDidMount() {
    this.refs.sbar.focus();
  }
}

Answer 1

What seems to me is that you are not using the refs the right way. The way you are using them has been deprecated. You should follow this syntax:

<input
   type="text"
   ref={(input) => { this.textInput = input; }}
 />

and when you want to access it you can do this.textInput. In your case, this.textInput.focus().