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TypeScript News Friday, April 6 Component, Component world components, Typescript & more…


What’s new?

  • The example page we are going to use contains several sections or blocks: – a header (these days, a large hero image taking the whole above-the-fold area)a section with a few imagesanother section with a heavy component like a mapa footerThe basic structure of a page we will be using…
  • class Observer extends Component { – constructor() { – super(); – this.state = { isVisible: false }; – this.io = null; – this.container = null; – } – componentDidMount() { – this.io = new IntersectionObserver([entry] = { – this.setState({ isVisible: entry.isIntersecting }); – }, {}); – } – componentWillUnmount() {…
  • this.props.children.map(child = child(this.state.isVisible)) – : /div – ); – } – }The component uses IntersectionObserver to detect that the container intersects with the viewport, that is, its visible.
  • Now, we can use this component to lazy load two of our components, Gallery and Map: – const Page = () = { – div – Header / – Observer – {isVisible = Gallery isVisible /} – /Observer – Observer – {isVisible = Map isVisible /} – /Observer – Footer…
  • Lets take a look at the Map: – class Map extends Component { – constructor() { – super(); – this.state = { initialized: false }; – this.map = null; – } – – initializeMap() { – this.setState({ initialized: true }); – // loadScript loads an external script, its definition is…

Tags: component, components, component world components, Google Map, High Order Components


  • TypeScript is a super set of JavaScript that adds a lot of features that are just missing from JavaScript, even with the enhancements from ES6/7.
  • Step 0: SetUpIll be using create-react-app for this project, with the custom React script for Typescript, so that we can keep the zero configuration and ease of use.
  • Now for the TypeScript specific thing, we have to specify types.
  • Unlike normal JavaScript, our code wont run if things are of the wrong type.
  • And I believe that is all the new things happening in this app because of TypeScript.

Tags: typescript, TypeScript specific thing, custom React script, Local Weather project, static typing


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Tags: cookies, session cookies, Persistent Cookies, proprietary machine-learning algorithm, temporary cookies


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