A basic form with React

Question

I have been working of a basic from using React and I need your help to improve this part of my code, especially validate and onSubmit.

state = {
    email: "",
    emailError: "",
  }; 
  change = e => {
    this.setState({
      [e.target.name]: e.target.value
    });
  };

    validate = () => {
    let isError = false;
     const errors = {
      emailError: "",
    };

    if (this.state.email.indexOf("@") === -1) {
      isError = true;
      errors.emailError = "Requires valid email";
    }

    this.setState({
      ...this.state,
      ...errors
    });

    return isError;
  }; 
  onSubmit = e => {
    e.preventDefault();
    const err = this.validate();
    if (!err) {
      this.props.onSubmit(this.state);
      this.setState({

        email: "",
        emailError: "",
      });
    }
  };

  render() {
    return (
      <form>
        <TextField
          name="email"
          hintText="Email"
          floatingLabelText="Email"
          value={this.state.email}
          onChange={e => this.change(e)}
          errorText={this.state.emailError}
          floatingLabelFixed
        />
        <br />
        <RaisedButton label="Submit" onClick={e => this.onSubmit(e)} primary />
      </form>
    );

Answer 1

As far as I'm aware, CodeReview is for completed programs. I imagine that this question would be better suited in StackOverflow. That being said, I see no point in duping the question on a different site.

Without seeing the rest of the program, and solely in a time interest, I'd say you keep the change function and ignore the validations. If you want a form field to be required, you can add 'required' to the input.

<form>
  <input type="text" name="input1" value={this.state.input1} onChange={e => this.change(e)} required />
</form>

You can find more on the MDN web docs for the required attribute.

Side note: you can also bind this.change as this.change = this.change.bind(this) in the constructor if you intend on using it for multiple fields. It'll save you some bytes, but if it's just a one off, binding it in the element itself like you have should be fine.