Exploring the React Context API with Provider and Consumer

  • It explains how to use React’s new context API for passing props down the component tree.
  • Basically, React’s context API takes the clutter away of passing mandatory props, that are needed by every component, down your whole component tree.
  • Therefore you could use React’s context API to give every component access to the colored theme.
  • As you can imagine, following this way every component that needs to be styled according to the colored theme could get the necessary information from React’s context API by using the Consumer component now.
  • This Provider component uses React’s context API to pass down the state implicitly.

React’s Context API is a powerful feature for passing props down the component tree without the need to tell components in between about them. React’s context creates a Provider and Consumer component that enable us to use this powerful feature …
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Using RxJS with React.js: Part 3 — Dispatching events from Component

  • (Check out FrintJS on GitHub for more documentation on combining the power of RxJS with React)Illustration of unidirectional flow between Subject and ComponentUnidirectional cycleEarlier we saw an example of HoC streaming props to the base component.
  • Let’s now look at ways how we can dispatch events from inside the base component, update some value, and the updated value will then be streamed back to the component completing one unidirectional cycle.We can take the example of a form input field.
  • To keep things simple, let’s say BehaviorSubject is a kind of Subject, that can already start with an initial value.import { BehaviorSubject } from ‘rxjs’;const subject$ = new = console.log(x)); // prints `foo` right awayThe base Component with form inputLet’s say this is our base component:import React from ‘react’const MyComponent =…
  • First one is a stream of the input value, and the latter for handling the change.import { BehaviorSubject, Observable } from ‘rxjs’;const formInput$ = new BehaviorSubject(‘foo’); // with initial valueconst handlers$ = Observable.of({ handleChange: value = formInput$.
  • scan(function (props, emitted) { return { …props, …emitted }; });Observing the base ComponentNow that we have the props$ observable ready, we can integrate it with our base complement easily using the observe function from FrintJS:import { observe } from ‘frint-react’;const ObservedRoot = observe(function () { return props$;})(MyComponent);Now you can stream…

Earlier we saw an example of HoC streaming props to the base component. Let’s now look at ways how we can dispatch events from inside the base component, update some value, and the updated value will…
Continue reading “Using RxJS with React.js: Part 3 — Dispatching events from Component”

Simple tutorial to understand props vs state in React.js by @jjude

Simple tutorial to understand #props vs #state in #ReactJS - @jjude

  • Like parameters in functions, you can pass properties into react.js component.
  • If you want to understand the basics of React.js component, read Create React.js component with Typescript.
  • The property will be an input from the invoking component with the inital value for the Timer.
  • Let us see how to invoke this Timer component with an initial value.
  • Whenver a component calls , React.js calls its corresponding function.

Use props to send information to a component. Use state to manage information created and updated by a component.
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Using RxJS with React.js: Part 3 — Dispatching events from Component

Using RxJS with React.js: Part 3 - Dispatching events from Component

  • Using RxJS with React.js: Part 3 — Dispatching events from ComponentThis is the third part of the series.Illustration of unidirectional flow between Subject and ComponentUnidirectional cycleEarlier we saw an example of HoC streaming props to the base component.
  • Let’s now look at ways how we can dispatch events from inside the base component, update some value, and the updated value will then be streamed back to the component completing one unidirectional cycle.We can take the example of a form input field.
  • To keep things simple, let’s say BehaviorSubject is a kind of Subject, that can already start with an initial value.import { BehaviorSubject } from ‘rxjs’;const subject$ = new = console.log(x)); // prints `foo` right awayThe base Component with form inputLet’s say this is our base component:import React from ‘react’const MyComponent = React.createClass({ render() { const { value, handleChange } = this.props; return ( div input type=”text” value={value} onChange={e = handleChange(e.target.value)} / pCurrent value: {value}/p /div ); }});From the base component, we are accessing the props value and handleChange.
  • First one is a stream of the input value, and the latter for handling the change.import { BehaviorSubject, Observable } from ‘rxjs’;const formInput$ = new BehaviorSubject(‘foo’); // with initial valueconst handlers$ = Observable.of({ handleChange: value = formInput$.
  • scan(function (props, emitted) { return { …props, …emitted }; });Observing the base ComponentNow that we have the props$ observable ready, we can integrate it with our base complement easily using the observe function from FrintJS:import { observe } from ‘frint-react’;const ObservedRoot = observe(function () { return props$;})(MyComponent);Now you can stream the props, including both the input value and the change handler from your HoC, and also trigger changes in the Subject from your Component’s events.Live demoVisit this example in JSBin.

Earlier we saw an example of HoC streaming props to the base component. Let’s now look at ways how we can dispatch events from inside the base component, update some value, and the updated value will…
Continue reading “Using RxJS with React.js: Part 3 — Dispatching events from Component”