React Native: How to handle the deprecation of the lifecycle methods with ListView?

Question

I'm currently learning React Native. I want to write a ListView. The tutorial I'm following uses the deprecated method componentWillMount, which is now called UNSAFE_componentWillMount. I googled an people said one should replace that method with componentDidMount. My problem is when I add this method to my code, the app breaks.

Here is the code:

/* @flow */

import React, { Component } from "react";
import { ListView } from "react-native";
import { connect } from "react-redux";
import PropTypes from "prop-types";
import ListItem from "./ListItem";

class LibraryList extends Component {
  componentDidMount = () => {
    const ds = new ListView.DataSource({
      rowHasChanged: (r1, r2) => r1 !== r2
    });

    this.dataSource = ds.cloneWithRows(this.props.libraries);
  };

  renderRow = library => <ListItem library={library} />;

  render() {
    return <ListView dataSource={this.dataSource} renderRow={this.renderRow} />;
  }
}

LibraryList.propTypes = {
  libraries: PropTypes.array
};

const mapStateToProps = state => {
  return { libraries: state.libraries };
};

export default connect(mapStateToProps)(LibraryList);

And here is the error message that I get TypeError: Cannot read property 'rowIdentities' of undefined. Which method am I supposed to use here, or how can I fix this?

Answer 1

I solved the problem by using a FlatList instead. I found out that ListView is deprecated :) Here is the code I ended up using:

/* @flow */

import React, { Component } from "react";
import { FlatList } from "react-native";
import { connect } from "react-redux";
import PropTypes from "prop-types";
import ListItem from "./ListItem";

class LibraryList extends Component {
  state = {
    dataSource: []
  };
  componentDidMount = () => {
    this.setState({ dataSource: this.props.libraries });
  };

  renderRow = ({ item: library }) => <ListItem library={library} />;

  render() {
    return (
      <FlatList
        data={this.state.dataSource}
        renderItem={this.renderRow}
        keyExtractor={item => item.id.toString()}
      />
    );
  }
}

LibraryList.propTypes = {
  libraries: PropTypes.array
};

const mapStateToProps = state => {
  return { libraries: state.libraries };
};

export default connect(mapStateToProps)(LibraryList);