Java Script
JavaScript (not to be confused with Java) is a high-level, dynamic, multi-paradigm, weakly-typed language used for both client-side and server-side scripting. Its primary use is in rendering and allowing manipulation of web pages. Use this tag for questions regarding ECMAScript and its various dialects/implementations (excluding ActionScript and Google-Apps-Script).
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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
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20
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855
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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
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15
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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
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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
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30
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2.7K
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Invariant Violation: Objects are not valid as a React child
In my component's render function I have: render() { const items = ['EN', 'IT',
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16
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1.1K
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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
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18
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547
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How can I update the parent's state in React?
My structure looks as follows: Component 1 - |- Component 2 - - |- Component 4 - - - |- Component 5
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30
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2.6K
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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
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14
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1.3K
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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
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16
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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
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30
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2.3K
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How to update nested state properties in React
I'm trying to organize my state by using nested property like this: this.state = { someProperty: {
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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
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9
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1.1K
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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
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7
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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
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30
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670
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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
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30
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Detect click outside React component
I'm looking for a way to detect if a click event happened outside of a component, as described in this ar
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18
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2.3K
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A component is changing an uncontrolled input of type text to be controlled error in ReactJS
Warning: A component is changing an uncontrolled input of type text to be controlled. Input elements should
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30
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3K
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What is the difference between state and props in React?
I was watching a Pluralsight course on React and the instructor stated that props should not be changed. I&apo
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30
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Show or hide element in React
I am messing around with React.js for the first time and cannot find a way to show or hide something on a page
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Call child method from parent
I have two components: Parent component Child component I was trying to call Child's method from Parent,