reactjs

Error: ‘node-sass’ version 5.0.0 is incompatible with ^4.0.0

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TL;DR npm uninstall node-sass npm install [email protected] Or, if using Yarn (default in newer CRA versions) yarn remove node-sass yarn add [email protected] Edit2: sass-loader v10.0.5 fixes it. The problem is you might not be using it as a project dependency, but more as a dependency of your dependencies. CRA uses a fixed version, angular-cli locks to node-sass v4, and so on. … Read more

Preset files are not allowed to export objects

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You’re using a combination of Babel 6 and Babel 7. There is no guarantee of compatibility across versions: should be and would be I’m also confused because you didn’t mention @babel/proposal-class-properties in your package.json, but assuming it is in there it should also be updated.

Understanding the React Hooks ‘exhaustive-deps’ lint rule

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The reason the linter rule wants onChange to go into the useEffect hook is because it’s possible for onChange to change between renders, and the lint rule is intended to prevent that sort of “stale data” reference. For example: Every single render of MyParentComponent will pass a different onChange function to MyCustomComponent. In your specific case, you probably don’t care: you only want to call onChange when the … Read more

how to delete a single item using axios in react

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You are not specifying what your Post component should delete. In other words, the props.delete is not receiving an id to pass up to your parent component. In order to do that, you can change that to () => props.delete(props.id) and then in your parent component you need to have the handleDelete method receive the id of the item you want to target which is the id we passed … Read more

How to use clsx in React

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clsx is generally used to conditionally apply a given className This syntax means that some class will only be applied if a given condition evaluates to true In this example [classes.menuOpen] (which will evaluate to something like randomclassName123) will only be applied if open === true clsx basically outputs a string interpolation. So you don’t have to necessarily use it, although is a common practice. … Read more

How to use clsx in React

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clsx is generally used to conditionally apply a given className This syntax means that some class will only be applied if a given condition evaluates to true In this example [classes.menuOpen] (which will evaluate to something like randomclassName123) will only be applied if open === true clsx basically outputs a string interpolation. So you don’t have to necessarily use it, although is a common practice. … Read more

What is mapDispatchToProps?

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I feel like none of the answers have crystallized why mapDispatchToProps is useful. This can really only be answered in the context of the container-component pattern, which I found best understood by first reading:Container Components then Usage with React. In a nutshell, your components are supposed to be concerned only with displaying stuff. The only place they are supposed to get information from is … Read more

How do I reference a local image in React?

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First of all wrap the src in {} Then if using Webpack; Instead of: <img src={“./logo.jpeg”} /> You may need to use require: <img src={require(‘./logo.jpeg’)} /> Another option would be to first import the image as such: import logo from ‘./logo.jpeg’; // with import or … const logo = require(‘./logo.jpeg); // with require then plug it in… … Read more

When to use componentWillReceiveProps lifecycle method?

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componentWillReceiveProps is required if you want to update the state values with new props values, this method will get called whenever any change happens to props values. In your case why you need this componentWillReceiveProps method? Because you are storing the props values in state variable, and using it like this: this.state.KeyName That’s why you … Read more