Welcome to the Treehouse Community

Want to collaborate on code errors? Have bugs you need feedback on? Looking for an extra set of eyes on your latest project? Get support with fellow developers, designers, and programmers of all backgrounds and skill levels here with the Treehouse Community! While you're at it, check out some resources Treehouse students have shared here.

Looking to learn something new?

Treehouse offers a seven day free trial for new students. Get access to thousands of hours of content and join thousands of Treehouse students and alumni in the community today.

Start your free trial

JavaScript React Components (2018) Managing State and Data Flow Controlled Components

Steven Matos
Steven Matos
9,162 Points
Posted by Steven Matos
Steven Matos
9,162 Points

TypeError: Cannot read property 'value' of null

So I am following along the video and its telling me that there is a problem with my line of value.

import React, { Component } from 'react';

class AddPlayerForm extends Component {

state: { value:'' };

handleValueChange = (e) => { this.setState({ value: e.target.value }); }

handleSubmits = (e) => { e.preventDefault(); this.props.addPlayer(this.state.value); }

render(){ return (

  <form onSubmit={this.handleSubmits}>
    <input
      type="text"
      value={this.state.value} // this line has TypeError //
      onChange={this.handleValueChange}
      placeholder="Enter a player's name"
    />
    <input
      type="submit"
      value="Add Player"
    />
  </form>
);

} }

export default AddPlayerForm;

1 Answer

KRIS NIKOLAISEN
KRIS NIKOLAISEN
54,971 Points

Instead of:

state: {
 value: ''
 };

try:

state = {
    value: ''
 };
Steven Matos
Steven Matos
9,162 Points
Steven Matos
Steven Matos
9,162 Points

thank you very much!