Using redux-form I'm losing focus after typing the first character

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 😔😔😔😔:

     //.....

     <Field name="email" type="text" component={renderField('input')} label="Email Address" />
     <Field name="desc" component={renderField('textarea')} label="Email Address" />

But , do the following 🙂🙂🙂🙂 :

  // outside component class
  const InputField = renderField('input');
  const TextAreaField = renderField('textarea');

   // inside component class
  <Field name="email" type="text" component={InputField} label="Email Address" />
  <Field name="desc" component={TextAreaField} label="Email Address" />

回答3:

What worked for me was refactoring arrowFunction-based Component to class-based Component as the behavior of InputForm components was weird. Every time the value of each input was changed they all rerendered even after splitting each inputType to separated components. There was nothing else left to fix but changing main component to class-based. I guess it may be caused by redux-form itself.

回答4:

I had the same problem. I solved it when I added my react redux form to the store in the createForms():

export const ConfigureStore = () => {
  const store = createStore(
    combineReducers({

      tasks: Tasks,
      task: Task,
      image: Image,
      admin: Admin,
      pageId: PageID,
      fieldValues: FieldValues,
      formValues: FormValues,

      ...createForms({
        createTask: initialTask,
        editTask: initialEditTask
      })
    }),
    applyMiddleware(thunk, logger)
  );

  return store;
}

来源：https://stackoverflow.com/questions/39839051/using-redux-form-im-losing-focus-after-typing-the-first-character