Perform debounce in React.js

Question

How do you perform debounce in React.js?

I want to debounce the handleOnChange.

I tried with debounce(this.handleOnChange, 200) but it doesn\'t

Answer 1

Just another variant with recent react and lodash.

class Filter extends Component {
  static propTypes = {
    text: PropTypes.string.isRequired,
    onChange: PropTypes.func.isRequired
  }

  state = {
    initialText: '',
    text: ''
  }

  constructor (props) {
    super(props)

    this.setText = this.setText.bind(this)
    this.onChange = _.fp.debounce(500)(this.onChange.bind(this))
  }

  static getDerivedStateFromProps (nextProps, prevState) {
    const { text } = nextProps

    if (text !== prevState.initialText) {
      return { initialText: text, text }
    }

    return null
  }

  setText (text) {
    this.setState({ text })
    this.onChange(text)
  }

  onChange (text) {
    this.props.onChange(text)
  }

  render () {
    return (<input value={this.state.text} onChange={(event) => this.setText(event.target.value)} />)
  }
}

Answer 2

I was searching for a solution to the same problem and came across this thread as well as some others but they had the same problem: if you are trying to do a handleOnChange function and you need the value from an event target, you will get cannot read property value of null or some such error. In my case, I also needed to preserve the context of this inside the debounced function since I'm executing a fluxible action. Here's my solution, it works well for my use case so I'm leaving it here in case anyone comes across this thread:

// at top of file:
var myAction = require('../actions/someAction');

// inside React.createClass({...});

handleOnChange: function (event) {
    var value = event.target.value;
    var doAction = _.curry(this.context.executeAction, 2);

    // only one parameter gets passed into the curried function,
    // so the function passed as the first parameter to _.curry()
    // will not be executed until the second parameter is passed
    // which happens in the next function that is wrapped in _.debounce()
    debouncedOnChange(doAction(myAction), value);
},

debouncedOnChange: _.debounce(function(action, value) {
    action(value);
}, 300)

Answer 3

for throttle or debounce the best way is to create a function creator so you can use it any where, for example:

  updateUserProfileField(fieldName) {
    const handler = throttle(value => {
      console.log(fieldName, value);
    }, 400);
    return evt => handler(evt.target.value.trim());
  }

and in your render method you can do:

<input onChange={this.updateUserProfileField("givenName").bind(this)}/>

the updateUserProfileField method will create a separated function each time you call it.

Note don't try to return the handler directly for example this will not work:

 updateUserProfileField(fieldName) {
    return evt => throttle(value => {
      console.log(fieldName, value);
    }, 400)(evt.target.value.trim());
  }

the reason why this will not work because this will generate a new throttle function each time the event called instead of using the same throttle function, so basically the throttle will be useless ;)

Also if you use debounce or throttle you don't need setTimeout or clearTimeout, this is actually why we use them :P

Answer 4

Here's a snippet using @Abra's approach wrapped in a function component (we use fabric for the UI, just replace it with a simple button)

import React, { useCallback } from "react";
import { debounce } from "lodash";

import { PrimaryButton, DefaultButton } from 'office-ui-fabric-react/lib/Button';

const debounceTimeInMS = 2000;

export const PrimaryButtonDebounced = (props) => {

    const debouncedOnClick = debounce(props.onClick, debounceTimeInMS, { leading: true });

    const clickHandlerDebounced = useCallback((e, value) => {

        debouncedOnClick(e, value);

    },[]);

    const onClick = (e, value) => {

        clickHandlerDebounced(e, value);
    };

    return (
        <PrimaryButton {...props}
            onClick={onClick}
        />
    );
}

Answer 5

A nice and clean solution, that doesn't require any external dependencies:

Debouncing with React Hooks

It uses a custom plus the useEffect React hooks and the setTimeout / clearTimeout method.

Answer 6

My solution is hooks based (written in Typescript).

I've got 2 main hooks useDebouncedValue and useDebouncedCallback

First - useDebouncedValue

Let's say we've got a search box, but we want to ask the server for search results after the user has stopped typing for 0,5s

function SearchInput() {
  const [realTimeValue, setRealTimeValue] = useState('');

  const debouncedValue = useDebouncedValue(realTimeValue, 500); // this value will pick real time value, but will change it's result only when it's seattled for 500ms

  useEffect(() => {
    // this effect will be called on seattled values
    api.fetchSearchResults(debouncedValue);
  }, [debouncedValue])

  return <input onChange={event => setRealTimeValue(event.target.value)} />
}

Implementation

import { useState, useEffect } from "react";

export function useDebouncedValue<T>(input: T, time = 500) {
  const [debouncedValue, setDebouncedValue] = useState(input);

  // every time input value has changed - set interval before it's actually commited
  useEffect(() => {
    const timeout = setTimeout(() => {
      setDebouncedValue(input);
    }, time);

    return () => {
      clearTimeout(timeout);
    };
  }, [input, time]);

  return debouncedValue;
}

Second useDebouncedCallback

It just creates a 'debounced' function in the scope of your component.

Let's say we've got a component with a button that will show alert 500ms after you stopped clicking it.

function AlertButton() {
  function showAlert() {
    alert('Clicking has seattled');
  }

  const debouncedShowAlert = useDebouncedCallback(showAlert, 500);

  return <button onClick={debouncedShowAlert}>Click</button>
}

Implementation (note I'm using lodash/debounce as a helper)

import debounce from 'lodash/debounce';
import { useMemo } from 'react';

export function useDebouncedCallback<T extends (...args: any) => any>(callback: T, wait?: number) {
  const debouncedCallback = useMemo(() => debounce(callback, wait), [callback, wait]);

  return debouncedCallback;
}