From headline‘ style remove height, justifyContent and alignItems. It will center the text vertically. Add textAlign: ‘center’ and it will center the text horizontally. headline: { textAlign: ‘center’, // <– the magic fontWeight: ‘bold’, fontSize: 18, marginTop: 0, width: 200, backgroundColor: ‘yellow’, }
The issue becomes extremely simple when you realize that an Angular service is just an object which delivers a set of context-independent methods. It’s just the Angular DI mechanism which makes it look more complicated. The DI is useful as it takes care of creating and maintaining instances for you but you don’t really need … Read more
There are a few ways to do this: 1) Get values from array of form elements by index handleSubmit = (event) => { event.preventDefault(); console.log(event.target[0].value) } 2) Using name attribute in html handleSubmit = (event) => { event.preventDefault(); console.log(event.target.elements.username.value) // from elements property console.log(event.target.username.value) // or directly } <input type=”text” name=”username”/> 3) Using refs handleSubmit … Read more
The wording of the error message corresponds to what you get from Google Chrome when you run JSON.parse(‘<…’). I know you said the server is setting Content-Type:application/json, but I am led to believe the response body is actually HTML. Feed.js:94 undefined “parsererror” “SyntaxError: Unexpected token < in JSON at position 0” with the line console.error(this.props.url, … Read more
This is a confusion between constructors and instances. Remember that when you write a component in React: class Greeter extends React.Component<any, any> { render() { return <div>Hello, {this.props.whoToGreet}</div>; } } You use it this way: return <Greeter whoToGreet=”world” />; You don’t use it this way: let Greet = new Greeter(); return <Greet whoToGreet=”world” />; In … Read more
React (or JSX) doesn’t support variable interpolation inside an attribute value, but you can put any JS expression inside curly braces as the entire attribute value, so this works: <img className=”image” src={“images/” + this.props.image} />
According to React Doc, you could listen to keyboard events, like onKeyPress or onKeyUp, not onChange. var Input = React.createClass({ render: function () { return <input type=”text” onKeyDown={this._handleKeyDown} />; }, _handleKeyDown: function(e) { if (e.key === ‘Enter’) { console.log(‘do validate’); } } }); Update: Use React.Component Here is the code using React.Component which does the … Read more
I’m encountering a similar issue and found two solutions that work as far as viewing the application directly in a browser ngrok http 8080 –host-header=”localhost:8080″ ngrok http –host-header=rewrite 8080 obviously, replace 8080 with whatever port you’re running on this solution still raises an error when I use this in an embedded page, that pulls the … Read more
Using Hooks (React 16.8.0+) Create a useWindowDimensions hook. import { useState, useEffect } from ‘react’; function getWindowDimensions() { const { innerWidth: width, innerHeight: height } = window; return { width, height }; } export default function useWindowDimensions() { const [windowDimensions, setWindowDimensions] = useState(getWindowDimensions()); useEffect(() => { function handleResize() { setWindowDimensions(getWindowDimensions()); } window.addEventListener(‘resize’, handleResize); return () … Read more
You need to use useEffect hook to achieve this. const [counter, setCounter] = useState(0); const doSomething = () => { setCounter(123); } useEffect(() => { console.log(‘Do something after counter has changed’, counter); }, [counter]); If you want the useEffect callback to be ignored during the first initial render, then modify the code accordingly: import React, … Read more