Using redux-form I'm losing focus after typing

问题:

I'm using redux-form and on blur validation. After I type the first character into an input element, it loses focus and I have to click in it again to continue typing. It only does this with the first character. Subsequent characters types remains focuses. Here's my basic sign in form example:

import React, { Component } from 'react';
import { connect } from 'react-redux';
import { Field, reduxForm } from 'redux-form';
import * as actions from '../actions/authActions';

require('../../styles/signin.scss');


class SignIn extends Component {

  handleFormSubmit({ email, password }) {
    this.props.signinUser({ email, password }, this.props.location);
  }

  renderAlert() {
    if (this.props.errorMessage) {
      return (
        <div className="alert alert-danger">
          {this.props.errorMessage}
        </div>
      );
    } else if (this.props.location.query.error) {
      return (
        <div className="alert alert-danger">
          Authorization required!
        </div>
      );
    }
  }

  render() {

    const { message, handleSubmit, prestine, reset, submitting } = this.props;

    const renderField = ({ input, label, type, meta: { touched, invalid, error } }) => (
      <div class={`form-group ${touched && invalid ? 'has-error' : ''}`}>
        <label for={label} className="sr-only">{label}</label>
        <input {...input} placeholder={label} type={type} className="form-control" />
        <div class="text-danger">
          {touched ? error: ''}
        </div>
      </div>
    );


    return (
      <div className="row">
        <div className="col-md-4 col-md-offset-4">
          <form onSubmit={handleSubmit(this.handleFormSubmit.bind(this))} className="form-signin">
            <h2 className="form-signin-heading">
              Please sign in
            </h2>
            {this.renderAlert()}
            <Field name="email" type="text" component={renderField} label="Email Address" />
            <Field name="password" type="password" component={renderField} label="Password" />
            <button action="submit" className="btn btn-lg btn-primary btn-block">Sign In</button>
          </form>
        </div>
        </div>
    );
  }
}

function validate(values) {
  const errors = {};

  if (!values.email) {
    errors.email = 'Enter a username';
  }

  if (!values.password) {
    errors.password = 'Enter a password'
  }

  return errors;
}

function mapStateToProps(state) {
  return { errorMessage: state.auth.error }
}

SignIn = reduxForm({
  form: 'signin',
  validate: validate
})(SignIn);

export default connect(mapStateToProps, actions)(SignIn);

回答1:

This happens because you're re-defining renderField as a new component every time you render which means it looks like a new component to React so it'll unmount the original one and re-mounts the new one.

You'll need to hoist it up:

const renderField = ({ input, label, type, meta: { touched, invalid, error } }) => (
      <div class={`form-group ${touched && invalid ? 'has-error' : ''}`}>
        <label for={label} className="sr-only">{label}</label>
        <input {...input} placeholder={label} type={type} className="form-control" />
        <div class="text-danger">
          {touched ? error: ''}
        </div>
      </div>
    );

class SignIn extends Component {

  ...

  render() {
    const { message, handleSubmit, prestine, reset, submitting } = this.props;


    return (
      <div className="row">
        <div className="col-md-4 col-md-offset-4">
          <form onSubmit={handleSubmit(this.handleFormSubmit.bind(this))} className="form-signin">
            <h2 className="form-signin-heading">
              Please sign in
            </h2>
            {this.renderAlert()}
            <Field name="email" type="text" component={renderField} label="Email Address" />
            <Field name="password" type="password" component={renderField} label="Password" />
            <button action="submit" className="btn btn-lg btn-primary btn-block">Sign In</button>
          </form>
        </div>
        </div>
    );
  }
}

...

回答2:

As @riscarrott mentioned, put renderField outside of component class .

But I am still losing focus .. And after testing, I concluded the re-rendering is done because of using curried function (return another function, and not return element . directly) .

const const renderField = (InputComponent = 'input') => ({ input, label, type, meta: { touched, invalid, error } }) => (
      <div class={`form-group ${touched && invalid ? 'has-error' : ''}`}>
        <label for={label} className="sr-only">{label}</label>
        <InputComponent {...input} placeholder={label} type={type} className="form-control" />
        <div class="text-danger">
          {touched ? error: ''}
        </div>
      </div>
    );

Then, if your renderField is a curried function :

then , don't do