Clarify useEffect caveats #6910
Merged
Conversation
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
|
The latest updates on your projects. Learn more about Vercel for Git ↗︎
|
Size changes📦 Next.js Bundle Analysis for react-devThis analysis was generated by the Next.js Bundle Analysis action. 🤖 This PR introduced no changes to the JavaScript bundle! 🙌 |
rachitiitr
reviewed
May 25, 2024
| * Even if your Effect was caused by an interaction (like a click), **the browser may repaint the screen before processing the state updates inside your Effect.** Usually, that's what you want. However, if you must block the browser from repainting the screen, you need to replace `useEffect` with [`useLayoutEffect`.](/reference/react/useLayoutEffect) | ||
| * If your Effect is caused be an interaction (like a click), **React may run your Effect before the browser paints the updated screen**. This ensures that the result of the Effect can be observed by the event system. Usually, this works as expected. However, if you must defer the work until after paint, such as an `alert()`, you can use `setTimeout`. See [reactwg/react-18/128](https://github.com/reactwg/react-18/discussions/128) for more information. | ||
|
|
||
| * Even if your Effect was caused by an interaction (like a click), **React may allow the browser may repaint the screen before processing the state updates inside your Effect.** Usually, this works as expected. However, if you must block the browser from repainting the screen, you need to replace `useEffect` with [`useLayoutEffect`.](/reference/react/useLayoutEffect) |
There was a problem hiding this comment.
Do we want to fix the below typo?
... React may allow the browser
mayto repaint the screen ...
There was a problem hiding this comment.
I have opened a PR to address the same, please help review and merge #6911
Sign up for free
to join this conversation on GitHub.
Already have an account?
Sign in to comment
Add this suggestion to a batch that can be applied as a single commit.
This suggestion is invalid because no changes were made to the code.
Suggestions cannot be applied while the pull request is closed.
Suggestions cannot be applied while viewing a subset of changes.
Only one suggestion per line can be applied in a batch.
Add this suggestion to a batch that can be applied as a single commit.
Applying suggestions on deleted lines is not supported.
You must change the existing code in this line in order to create a valid suggestion.
Outdated suggestions cannot be applied.
This suggestion has been applied or marked resolved.
Suggestions cannot be applied from pending reviews.
Suggestions cannot be applied on multi-line comments.
Suggestions cannot be applied while the pull request is queued to merge.
Suggestion cannot be applied right now. Please check back later.
Add clarification for question in facebook/react#29584