Questions tagged [react-strictmode]

26 questions
209
votes
6 answers

My React Component is rendering twice because of Strict Mode

My React Component is rendering twice. So, I decided to do a line-by-line debug, and the problem is here: if ( workInProgress.mode & StrictMode) { instance.render(); } React-dom.development.js Is it because of the strict mode? Can I…
Marry Joanna
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156
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13 answers

Warning: findDOMNode is deprecated in StrictMode. findDOMNode was passed an instance of Transition which is inside StrictMode

I am trying to use a function as a prop inside a component and this component is a child of another component. But the function is not working.? Can I know why. This is the warning i am receiving in the console. Warning: findDOMNode is deprecated…
Niroshan_Krish
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90
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4 answers

What is StrictMode in React?

I heard that strict mode helps to write React code in best practices way by throwing warnings for life cycle methods removal. I read about it from this article on Medium. Is my understanding correct? How effective is strict mode? Is it only for…
Hemadri Dasari
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24
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1 answer

findDOMNode is deprecated in StrictMode. findDOMNode was passed an instance of DraggableCore which is inside StrictMode

Draggable package is causing an error in strict mode: Warning: findDOMNode is deprecated in StrictMode. findDOMNode was passed an instance of DraggableCore which is inside StrictMode. Instead, add a ref directly to the element you want to…
Francesco Orsi
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19
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6 answers

React 18 strict mode causing component to render twice

The changes to strict-mode in React version 18 causes my code to render twice, which causes an error in axios abort controller, but I don't know how to clear the error from the browser console after the app renders twice. Please note: I am working…
neil
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17
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4 answers

How to disable react strict mode on third party libraries

We use strict mode in our React app. But third parties does not use strict mode. How can I achieve this?
babbego
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16
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3 answers

React / Reactstrap Warning: Legacy context API has been detected within a strict-mode tree

This is brand new install - I have not put any transitions on the Alert component To replicate the code it is simple import React from "react"; import { Alert } from "reactstrap"; export const Index = () => { return (
Michael Nelles
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11
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2 answers

How to disable Strict Mode in React 18?

Simply, how can I disable Strict Mode in React 18? I'm using React 18 with create-react-app.
user20779272
10
votes
1 answer

Is there a way to check if React's `StrictMode` is on?

Is there a way in React -- either in code or via the React devtools -- to see if a component is being rendered in React's StrictMode? In my dream world, there would be some kind of constant I could console.log, say a bool of…
Erdős-Bacon
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10
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2 answers

Does strict mode work differently with React 18?

Consider the snippets below. With React 18, count gets printed twice to the console on every render but with React 17 it gets printed only once. React 18 Example: function App() { const [count, setCount] = React.useState(0); …
Developer
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9
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3 answers

Is it safe to change a ref's value during render instead of in useEffect?

I'm using useRef to hold the latest value of a prop so that I can access it later in an asynchronously-invoked callback (such as an onClick handler). I'm using a ref instead of putting value in the useCallback dependencies list because I expect the…
jtbandes
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7
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2 answers

Can I keep in my app but make it not render twice

I have my app inside a Strict Mode and it makes it difficult to run with my useEffect(). It basically logs all my values twice in the console which is not the result I want to achieve. useEffect(() => { console.log('logs some data') }, []); It…
Metgher Andrei
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7
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1 answer

Should I use React.StrictMode in my test suite?

First time posting a question :) I have a React application with: // index.js ReactDOM.render( , document.getElementById('root'), ); I have 24 jest test suites,…
Willow
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5
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1 answer

React 18 StrictMode first useEffect wrong state

another React 18 strict mode question. I'm aware React will call the render and effect functions twice to highlight potential memory leaks with the upcoming features. What I yet don't understand is how to properly handle that. My issue is that I…
fragsalat
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1 answer

Should I manualy disable React StrictMode in production?

I was reading the doc and learned that React StrictMode is for development only, and it explains why we have double invoke. That's great, but does it mean I have to disable the StrictMode manualy for my production, or does react build command does…
Johan
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