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const React = require("react");
const Lifecycles = React.createLifecycleEvents({
didMount({ setState }) {
setState({
disabled: false,
});
},
didUpdate({ inputRef }) {
if (document.activeElement !== inputRef.value) {
@bvaughn
bvaughn / create-subscriber-component-poc.js
Last active September 30, 2018 09:55
create-subscriber-component proof of concept
type SubscribableConfig = {
// Maps property names of subscribable data sources (e.g. 'someObservable'),
// To state names for subscribed values (e.g. 'someValue').
subscribablePropertiesMap: {[subscribableProperty: string]: string},
// Synchronously get data for a given subscribable property.
// It is okay to return null if the subscribable does not support sync value reading.
getDataFor: (subscribable: any, propertyName: string) => any,
// Subscribe to a given subscribable.
@bvaughn
bvaughn / updating-subscriptions-when-props-change-example.js
Last active March 27, 2022 09:29
Advanced example for manually updating subscriptions in response to props changes in an async-safe way
// This is an advanced example! It is not typically required for application code.
// If you are using a library like Redux or MobX, use the container component provided by that library.
// If you are authoring such a library, use the technique shown below.
// This example shows how to safely update subscriptions in response to props changes.
// In this case, it is important to wait until `componentDidUpdate` before removing a subscription.
// In the event that a render is cancelled before being committed, this will prevent us from unsubscribing prematurely.
// We also need to be careful about how we handle events that are dispatched in between
// `getDerivedStateFromProps` and `componentDidUpdate` so that we don't put stale values into the `state`.
@markerikson
markerikson / NotificationManager.jsx
Created January 21, 2018 15:43
React / Redux / Semantic-UI toast notifications implementation
import React, {Component} from "react";
import {connect} from "react-redux";
import _ from "lodash";
import { Message } from "semantic-ui-react";
import {Portal} from 'react-portal';
import {selectNotifications} from "./notificationSelectors";
import {dismissNotification} from "./notificationActions";
@sebmarkbage
sebmarkbage / Infrastructure.js
Last active February 26, 2025 13:57
SynchronousAsync.js
let cache = new Map();
let pending = new Map();
function fetchTextSync(url) {
if (cache.has(url)) {
return cache.get(url);
}
if (pending.has(url)) {
throw pending.get(url);
}
@robertgonzales
robertgonzales / Frame.js
Created December 12, 2017 03:03
Use React portals to render inside shadow dom and iframes
class Frame extends Component {
componentDidMount() {
this.iframeHead = this.node.contentDocument.head
this.iframeRoot = this.node.contentDocument.body
this.forceUpdate()
}
render() {
const { children, head, ...rest } = this.props
return (
if (typeof window!=='undefined' && navigator.serviceWorker && navigator.serviceWorker.controller) {
let reloadOnNext = false;
let pushState = history.pushState;
history.pushState = function(state, title, url) {
pushState.call(this, state, title, url);
if (reloadOnNext===true) location.reload(true);
};
navigator.serviceWorker.controller.addEventListener('statechange', e => {
@busypeoples
busypeoples / UnderstandingReducer.re
Last active November 11, 2018 15:22
Understanding Reducer in ReasonML
let se = ReasonReact.stringToElement;
type state = int;
type actions =
| Inc
| IncWithSideEffect
| SideEffect
| DoNothing
| SilentIncUpdate
@joshuataylor
joshuataylor / app.js
Created October 23, 2017 12:31
Preact component to notify user when a change has been made, and on route change reload the page.
import { h, Component } from 'preact';
import { Router } from 'preact-router';
import Header from './header';
import Home from '../routes/home';
import Profile from '../routes/profile';
import NotifyChange from "./NotifyChange/index";
// import Home from 'async!../routes/home';
// import Profile from 'async!../routes/profile';
@busypeoples
busypeoples / FlowTutorial.js
Last active July 17, 2023 10:12
Flow Fundamentals For JavaScript Developers
//
// MIT License
//
// Copyright (c) 2018 Ali Sharif
//
// Permission is hereby granted, free of charge, to any person obtaining a copy
// of this software and associated documentation files (the "Software"), to deal
// in the Software without restriction, including without limitation the rights
// to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
// copies of the Software, and to permit persons to whom the Software is