57
votes
1
answers
1.1K
views
62
votes
4
answers
2.4K
views
In what situations would AJAX long/short polling be preferred over HTML5 WebSockets?
I am building a small chat application for friends, but unsure about how to get information in a timely manner
55
votes
21
answers
414
views
React Js conditionally applying class attributes
I want to conditionally show and hide this button group depending on what is passed in from the parent compone
55
votes
13
answers
1.2K
views
Invariant Violation: _registerComponent(...): Target container is not a DOM element
I get this error after a making trivial React example page: Uncaught Error: Invariant Violation: _register
61
votes
16
answers
1.2K
views
Setting a backgroundImage With React Inline Styles
I'm trying to access a static image to use within an inline backgroundImage property within React. Unfort
52
votes
21
answers
3.1K
views
Rerender view on browser resize with React
How can I get React to re-render the view when the browser window is resized? Background I have some blocks
58
votes
20
answers
858
views
React "after render" code?
I have an app where I need to set the height of an element (lets say "app-content") dynamically. It takes the
56
votes
15
answers
1.7K
views
useState set method not reflecting change immediately
I am trying to learn hooks and the useState method has made me confused. I am assigning an initial value to a
66
votes
13
answers
2.4K
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Error Running React Native App From Terminal (iOS)
I am following the tutorial on the official React Native website. Using the following to build my project: r
47
votes
30
answers
2.7K
views
Invariant Violation: Objects are not valid as a React child
In my component's render function I have: render() { const items = ['EN', 'IT',
67
votes
16
answers
1.2K
views
React - changing an uncontrolled input
I have a simple react component with the form which I believe to have one controlled input: import React from
69
votes
18
answers
550
views
How can I update the parent's state in React?
My structure looks as follows: Component 1 - |- Component 2 - - |- Component 4 - - - |- Component 5
57
votes
30
answers
2.6K
views
How to add multiple classes to a ReactJS Component?
I am new to ReactJS and JSX and I am having a little problem with the code below. I am trying to add multipl
59
votes
14
answers
1.3K
views
React JSX: selecting "selected" on selected <select> option
In a React component for a <select> menu, I need to set the selected attribute on the option that reflec
52
votes
16
answers
610
views
Correct modification of state arrays in React.js
I want to add an element to the end of a state array, is this the correct way to do it? this.state.arrayvar.pu
63
votes
30
answers
2.3K
views
How to update nested state properties in React
I'm trying to organize my state by using nested property like this: this.state = { someProperty: {
44
votes
16
answers
1.3K
views
Parse Error: Adjacent JSX elements must be wrapped in an enclosing tag
I am trying to set up my React.js app so that it only renders if a variable I have set is true. The way my
54
votes
9
answers
1.1K
views
Pros/cons of using redux-saga with ES6 generators vs redux-thunk with ES2017 async/await
There is a lot of talk about the latest kid in redux town right now, redux-saga/redux-saga. It uses generator
60
votes
7
answers
2K
views
ReactJS - Does render get called any time "setState" is called?
Does React re-render all components and sub components every time setState() is called? If so, why? I thought
59
votes
30
answers
674
views
Perform debounce in React.js
How do you perform debounce in React.js? I want to debounce the handleOnChange. I tried with debounce(this.h
