state

问题 Do you think this might be a flawlles solution to Check if Audio() is playing? Like when handling a stratup theme ... Place this above in the head songStarted = false; song = new Audio(); song.src = 'audio/startuptheme.mp3'; song.addEventListener('playing', (event) => {songStarted = true;}); song.play(); And use the following script anywhere (where first user interaction should happen), as many times as you need if (!songStarted){ if (typeof song == 'undefined'){ song = new Audio(); song.src

问题 I want to detect when a user quit my app and execute some code before but I don't know how to do this. I tried to use this package: https://pub.dev/packages/flutter_lifecycle_state but I have this error: flutter/.pub-cache/hosted/pub.dartlang.org/flutter_lifecycle_state-1.0.0/lib/flutter_lifecycle_state.dart:80:30: Error: Getter not found: 'suspending'. case AppLifecycleState.suspending If you have any solution for this problem or know another way to detect when a user quit my app it could be

问题 Building a small react app that passes the geolocation (determined by the browser to a child component as props). The first component: App.jsx import React, {Component} from 'react'; import DateTime from './components/dateTime/_dateTime.jsx'; import Weather from './components/weather/_weather.jsx'; import Welcome from './components/welcome/_welcome.jsx'; require ('../sass/index.scss'); export default class App extends Component { constructor() { super(); this.state = { latitude: '', longitude

问题 Building a small react app that passes the geolocation (determined by the browser to a child component as props). The first component: App.jsx import React, {Component} from 'react'; import DateTime from './components/dateTime/_dateTime.jsx'; import Weather from './components/weather/_weather.jsx'; import Welcome from './components/welcome/_welcome.jsx'; require ('../sass/index.scss'); export default class App extends Component { constructor() { super(); this.state = { latitude: '', longitude

问题 I am currently writing a sign-up page with react-js with react-hooks and I am still learning so please excuse me if this is a very simple question. I have a signup.js written in functional component with hooks. signup.js imports 'EmailTextField', 'PasswordTextField', 'NameTextField', 'CellPhoneTextField' ... components of which are also written in functional components with hooks. I made all these textfields as separate components to simplify the code as I have a requirement to have many

问题 Here's my situation: on this.handleFormSubmit() I am executing this.setState() inside this.handleFormSubmit(), I am calling this.findRoutes(); - which depends on the successful completion of this.setState() this.setState(); does not complete before this.findRoutes is called... How do I wait for this.setState() inside of this.handleFormSubmit() to finish before calling this.findRoutes()? A subpar solution: putting this.findRoutes() in componentDidUpdate() this is not acceptable because there

问题 Here's my situation: on this.handleFormSubmit() I am executing this.setState() inside this.handleFormSubmit(), I am calling this.findRoutes(); - which depends on the successful completion of this.setState() this.setState(); does not complete before this.findRoutes is called... How do I wait for this.setState() inside of this.handleFormSubmit() to finish before calling this.findRoutes()? A subpar solution: putting this.findRoutes() in componentDidUpdate() this is not acceptable because there

问题 I already have a state with this: this.setState({ conversation: ( <div> {conversation.map(element => { if (element.id === this.props.id) { return( <div className="row msg_container base_sent"> <div className="col-md-10 col-xs-10"> <div className="messages msg_sent"> <p>{element.message}</p> </div> </div> </div> ) } else { return( <div className="row msg_container base_receive"> <div className="col-md-10 col-xs-10"> <div className="messages msg_receive"> <p>{element.message}</p> </div> </div>

问题 I already have a state with this: this.setState({ conversation: ( <div> {conversation.map(element => { if (element.id === this.props.id) { return( <div className="row msg_container base_sent"> <div className="col-md-10 col-xs-10"> <div className="messages msg_sent"> <p>{element.message}</p> </div> </div> </div> ) } else { return( <div className="row msg_container base_receive"> <div className="col-md-10 col-xs-10"> <div className="messages msg_receive"> <p>{element.message}</p> </div> </div>

问题 I already have a state with this: this.setState({ conversation: ( <div> {conversation.map(element => { if (element.id === this.props.id) { return( <div className="row msg_container base_sent"> <div className="col-md-10 col-xs-10"> <div className="messages msg_sent"> <p>{element.message}</p> </div> </div> </div> ) } else { return( <div className="row msg_container base_receive"> <div className="col-md-10 col-xs-10"> <div className="messages msg_receive"> <p>{element.message}</p> </div> </div>