How to set focus on an input field after rendering?

Tutorial: How to set focus on an input field after rendering?

What’s the react way of setting focus on a particular text field after the component is rendered?

Documentation seems to suggest using refs, e.g:

Set ref="nameInput" on my input field in the render function, and then call:

this.refs.nameInput.getInputDOMNode().focus(); 

But where should I call this? I’ve tried a few places but I cannot get it to work.

Solutions How to set focus on an input field after rendering?

Solution 1: How to set focus on an input field after rendering?

You should do it in componentDidMount and refs callback instead. Something like this

componentDidMount(){
   this.nameInput.focus(); 
}
class App extends React.Component{
  componentDidMount(){
    this.nameInput.focus();
  }
  render() {
    return(
      <div>
        <input 
          defaultValue="Won't focus" 
        />
        <input 
          ref={(input) => { this.nameInput = input; }} 
          defaultValue="will focus"
        />
      </div>
    );
  }
}
    
ReactDOM.render(<App />, document.getElementById('app'));
<script src="https://cdnjs.cloudflare.com/ajax/libs/react/15.3.1/react.js"></script>
<script src="https://cdnjs.cloudflare.com/ajax/libs/react/15.3.1/react-dom.js"></script>
<div id="app"></div>

Solution 2: How to set focus on an input field after rendering?

Focus on mount

If you just want to focus an element when it mounts (initially renders) a simple use of the autoFocus attribute will do.

<input type="text" autoFocus />

Dynamic focus

to control focus dynamically use a general function to hide implementation details from your components.

React 16.8 + Functional component – useFocus hook

const FocusDemo = () => {

    const [inputRef, setInputFocus] = useFocus()

    return (
        <> 
            <button onClick={setInputFocus} >
               Focus
            </button>
            <input ref={inputRef} />
        </>
    )
    
}

const useFocus = () => {
    const htmlElRef = useRef(null)
    const setFocus = () => {htmlElRef.current &&  htmlElRef.current.focus()}

    return [ htmlElRef, setFocus ] 
}

Full Demo

React 16.3 + Class Components – utilizeFocus

class App extends Component {
  constructor(props){
    super(props)
    this.inputFocus = utilizeFocus()
  }

  render(){
    return (
      <> 
          <button onClick={this.inputFocus.setFocus}>
             Focus
          </button>
          <input ref={this.inputFocus.ref}/>
      </>
    )
  } 
}
const utilizeFocus = () => {
    const ref = React.createRef()
    const setFocus = () => {ref.current &&  ref.current.focus()}

    return {setFocus, ref} 
}

Full Demo

Solution 3: How to set focus on an input field after rendering?

React 16.3 added a new convenient way to handle this by creating a ref in the component’s constructor and using it like below:

class MyForm extends Component {
  constructor(props) {
      super(props);

      this.textInput = React.createRef();
  }

  componentDidMount() {
    this.textInput.current.focus();
  }

  render() {
    return(
      <div>
        <input ref={this.textInput} />
      </div>
    );
  }
}

For more details about React.createRef, you can check this article in React blog.

Update:

Starting from React 16.8useRef the hook can be used in function components to achieve the same result:

import React, { useEffect, useRef } from 'react';

const MyForm = () => {
  const textInput = useRef(null);

  useEffect(() => {
    textInput.current.focus();
  }, []);

  return (
    <div>
      <input ref={textInput} />
    </div>
  );
};

Solution 4: How to set focus on an input field after rendering?

I just ran into this issue and I’m using react 15.0.1 15.0.2 and I’m using ES6 syntax and didn’t quite get what I needed from the other answers since v.15 dropped weeks ago and some of the this.refs properties were deprecated and removed.

In general, what I needed was:

  1. Focus the first input (field) element when the component mounts
  2. Focus the first input (field) element with an error (after submit)

I’m using:

  • React Container/Presentation Component
  • Redux
  • React-Router

Focus on the First Input Element

I used autoFocus={true} on the first <input /> on the page so that when the component mounts, it will get focused.

Focus the First Input Element with an Error

This took longer and was more convoluted. I’m keeping out code that isn’t relevant to the solution for brevity.

Redux Store / State

I need a global state to know if I should set the focus and to disable it when it was set, so I don’t keep re-setting focus when the components re-render (I’ll be using componentDidUpdate() to check for setting focus.)

This could be designed as you see fit for you application.

{
    form: {
        resetFocus: false,
    }
}

Container Component

The component will need to have the resetfocus property set and a callBack to clear the property if it ends up setting focus on itself.

Also note, I organized my Action Creators into separate files mostly due to my project is fairly large and I wanted to break them up into more manageable chunks.

import { connect } from 'react-redux';
import MyField from '../presentation/MyField';
import ActionCreator from '../actions/action-creators';

function mapStateToProps(state) {
    return {
        resetFocus: state.form.resetFocus
    }
}

function mapDispatchToProps(dispatch) {
    return {
        clearResetFocus() {
            dispatch(ActionCreator.clearResetFocus());
        }
    }
}

export default connect(mapStateToProps, mapDispatchToProps)(MyField);

Presentation Component

import React, { PropTypes } form 'react';

export default class MyField extends React.Component {
    // don't forget to .bind(this)
    constructor(props) {
        super(props);
        this._handleRef = this._handleRef.bind(this);
    }

    // This is not called on the initial render so
    // this._input will be set before this get called
    componentDidUpdate() {
        if(!this.props.resetFocus) {
            return false;
        }

        if(this.shouldfocus()) {
            this._input.focus();
            this.props.clearResetFocus();
        }
    }

    // When the component mounts, it will save a 
    // reference to itself as _input, which we'll
    // be able to call in subsequent componentDidUpdate()
    // calls if we need to set focus.
    _handleRef(c) {
        this._input = c;
    }

    // Whatever logic you need to determine if this
    // component should get focus
    shouldFocus() {
        // ...
    }

    // pass the _handleRef callback so we can access 
    // a reference of this element in other component methods
    render() {
        return (
            <input ref={this._handleRef} type="text" />
        );
    }
}

Myfield.propTypes = {
    clearResetFocus: PropTypes.func,
    resetFocus: PropTypes.bool
}

Overview

The general idea is that each form field that could have an error and be focused needs to check itself and if it needs to set focus on itself.

There’s business logic that needs to happen to determine if the given field is the right field to set focus on. This isn’t shown because it will depend on the individual application.

When a form is submitted, that event needs to set the global focus flag resetFocus to true. Then as each component updates itself, it will see that it should check to see if it gets the focus and if it does, dispatch the event to reset focus so other elements don’t have to keep checking.

edit As a side note, I had my business logic in a “utilities” file and I just exported the method and called it within each shouldfocus() method.

Conclusion

I hope the How to set focus on an input field after rendering? the solution would be useful for you to learn something new from this solution. If it helped you then don’t forget to bookmark our site for more Quiz Answers and

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