Stack Overflow
Stack Overflow

Questions tagged [react-lifecycle-hooks]

Functions that provides visibility into React component life-cycle.

A component in React has a life-cycle, a number of different phases it goes through from birth to death. We can hook into those different phases to get some pretty fine grained control of our application.

To do this we add some specific methods to our component class which get called during each of these life-cycle phases, we call those methods hooks.

Reference

71 questions
14
votes
2 answers

Execute a function after Props change

I want to execute a function in Child Component after props gets changed in the Parent Component without having to manage an extra state in Child/Parent. {}} …
Neel Dsouza
  • 1,342
  • 4
  • 15
  • 33
14
votes
4 answers

How will React 0.14's Stateless Components offer performance improvements without shouldComponentUpdate?

This question has been going round and round in my head since I read the release notes (and other related hype) around React 0.14 - I'm a big fan of React and I think that stateless components…
Dan Roberts
  • 2,244
  • 16
  • 31
8
votes
3 answers

How to use componentWillUpdate in functional component by react hooks?

How to use componentWillUpdate in functional component by react hooks ?
DIXIT Kumar
  • 305
  • 2
  • 3
  • 12
5
votes
3 answers

Using React Hooks, why are my event handlers firing with the incorrect state?

I'm trying to create a copy of this spinning div example using react hooks. https://codesandbox.io/s/XDjY28XoV Here's my code so far import React, { useState, useEffect, useCallback } from 'react'; const App = () => { const [box, setBox] =…
Jon_B
  • 969
  • 4
  • 16
  • 24
4
votes
1 answer

How does firebase's onAuthStateChanged work in ComponentDidMount lifecycle in reactJS

Can anyone explain we how this onAuthStateChanged function is working inside componentDidMount. I know this lifecycle hook get executed only once when the component is mounted. So how does the function inside gets executed? What I assume is it's…
Amar
  • 135
  • 1
  • 11
4
votes
1 answer

How to Unmount a screen when moving to another in React Native

I'm developing a React Native app using React Navigation v4, React Hooks and ES6. I have 2 bottom tabs (Movies, Shows) and 4 screens with the following Stack structure: **Movies** -- MovieList -- MovieDetail **Shows** -- ShowList --…
Butri
  • 339
  • 8
  • 22
4
votes
2 answers

How does react decide to rerender a component

I know React has a life cycle method called shouldComponentUpdate, Which by default return true and that's how the component decides to update But How does that life cycle method gets called, When a state or props change for that component. What…
Shan
  • 613
  • 9
  • 21
3
votes
2 answers

useState place in lifecycle in react

I really want to understand the lifecycle of react functional component. In many websites you see these three steps: 1-mounthing 2-render 3-unmounthing. But what about other code that is written before useeffect() function for example assume…
bami
  • 211
  • 1
  • 6
  • 19
3
votes
2 answers

React functional component useEffect hook with dependency equal in class component lifecycles

I use the useEffect hook inside functional components with a dependency so that dependency changes , useEffect function will re-run like this : const [show, setShow] = React.useState(false); React.useEffect(() => { console.log("Do…
Mehdi Faraji
  • 2,574
  • 8
  • 28
  • 76
3
votes
1 answer

React hook useRender called twice if bailing and setting state afterward

I'm not sure if this is expected behavior, but if you bail out of a dispatch (https://reactjs.org/docs/hooks-reference.html#bailing-out-of-a-dispatch) while using the useReducer hook, the action occurs twice if it's followed by a render. Let me…
webbyweb
  • 385
  • 2
  • 11
2
votes
1 answer

useEffect is not triggered on redux store get updated

export default function Cart(props) { const dispatch = useDispatch(); const branch = useSelector((state) => get(state, "vendor.currentBranch")); const orderInput = useSelector((state) => get(state, "order.orderInputs")); const…
Nikhil Singhal
  • 51
  • 2
  • 6
2
votes
0 answers

renderChildren() functional component equivalent

I'm maintaining React app and I have to turn all class components into functional. One component has the renderChildren() method. Is there a way to mimic that method in a functional component with hooks? I really appreciate the support.
Jose Maselli
  • 23
  • 2
2
votes
2 answers

Unexpected keyword 'true' while using `useState` in react?

Here i am trying to set the open prop of the MUIDrawer to true when the user clicks it but while setting the state i am getting an error "Unexpected keyword 'true' " import React, { useState } from "react"; import { withRouter } from…
KALITA
  • 716
  • 2
  • 8
  • 20
2
votes
1 answer

Where the component gets mounted into, when we hit componentDidMount in react? is it real DOM or VirtualDom?

When will you hit the componentDidMount hook in react? is it when the component is mounted to the virtual dom or actual dom?
Charitha Goonewardena
  • 4,418
  • 2
  • 36
  • 38
2
votes
2 answers

Call Function On Mount in ReactJS

I have a problem calling a function when a component loads on ReactJS. I try to use componentDidMount() and has error compiling. Pls check my code below. Thanks export default function Customers() { const classes = useStyles(); const…
Joseph
  • 7,042
  • 23
  • 83
  • 181
1
2 3 4 5