state

Add element to a state React

由 ◇◆丶佛笑我妖孽 提交于 2020-04-28 20:43:16
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>

React dom not updating with Redux store

由 老子叫甜甜 提交于 2020-04-18 05:36:43
问题 I'm new to react-redux and I'm having an issue with a web-app I'm developing. The app should have a user log-in functionality, it should be able to fetch and display a list of games from a database api I made, and it should be able to display information for a specific game from that list when it's clicked. I have the user log-in functionality working perfectly, but the game list and specific game details don't initially display in the browser. If I look in the redux devtools, the action is

React dom not updating with Redux store

由 会有一股神秘感。 提交于 2020-04-18 05:36:39
问题 I'm new to react-redux and I'm having an issue with a web-app I'm developing. The app should have a user log-in functionality, it should be able to fetch and display a list of games from a database api I made, and it should be able to display information for a specific game from that list when it's clicked. I have the user log-in functionality working perfectly, but the game list and specific game details don't initially display in the browser. If I look in the redux devtools, the action is

Model Checking : Bad Prefixes using NFA

由 回眸只為那壹抹淺笑 提交于 2020-04-16 05:12:33
问题 We use NFA to model BadPrefixes for the safety property.I want to understand for a given Safety property , how to model the NFA. The following images are for reference. For instance, for safety property P2 ,Can someone explain how to know how many states are required(solution has 4) and which logic to use on the edges, how in Fig.,3 and Fig.4 , the edges are selected to satisfy the badprefixes P1 and P2.Thanks. 回答1: We have several definitions and notations here, let's go through these first:

设计模式----状态模式UML和实现代码

由 隐身守侯 提交于 2020-04-10 10:10:44
一、什么是状态模式？ 状态模式（State）定义： 当一个对象的内在状态改变时允许改变其行为，这个对象看起来像是改变了其类。 状态模式主要解决的是当控制一个对象状态的条件表达式过于复杂时的情况。把状态的判断逻辑转移到表示不同状态的一系列类中，可以把复杂的判断逻辑简化。 类型：形为型模式 顺口溜：中访策备迭 观 模命 状 职解 二、 状态 模式UML 三、JAVA代码实现 package com.amosli.dp.behavior.state; public abstract class State { public abstract void handle(Context context); } package com.amosli.dp.behavior.state; public class Context { private State state; public State getState() { return state; } public void setState(State state) { this.state = state; } public Context(State state) { this.state = state; } public void request() { state.handle(this); } } package com

How to change tintColor of whole app? SwiftUI

由 自闭症网瘾萝莉.ら 提交于 2020-03-20 05:58:32
问题 So, I am supporting three themes in my app, each with different tintColors. I'm using @EnvironmetObject to track changes. However, I can't use it on SceneDelegate.swift file, because the app crashes. Moreover, accentColor is not an option, as it doesn't change alert tintColor. How can I do it? Here's some code: SceneDelegate.swift file class SceneDelegate: UIResponder, UIWindowSceneDelegate { @EnvironmentObject var userData: UserData var window: UIWindow? func scene(_ scene: UIScene,

Why is the state mutating if I am using spread operator?

由 只谈情不闲聊 提交于 2020-02-25 03:59:48
问题 I have this code that I am testing on jsfiddle onVote = (dir, index) => { console.log(this.state) const products = [...this.state.products] products[index].votes = dir ? products[index].votes + 1 : products[index].votes - 1 console.log(this.state.products[index].votes) // this.setState({products}) }; https://jsfiddle.net/hkL3wug7/2/ However, even though I am not setting State, the console log shows that the state is changes every time I click on the plus and minus signs. I did the same as in

Why is the state mutating if I am using spread operator?

由 北城以北 提交于 2020-02-25 03:58:23
问题 I have this code that I am testing on jsfiddle onVote = (dir, index) => { console.log(this.state) const products = [...this.state.products] products[index].votes = dir ? products[index].votes + 1 : products[index].votes - 1 console.log(this.state.products[index].votes) // this.setState({products}) }; https://jsfiddle.net/hkL3wug7/2/ However, even though I am not setting State, the console log shows that the state is changes every time I click on the plus and minus signs. I did the same as in

Android SDK Media Recorder. State 4

由 两盒软妹~` 提交于 2020-02-23 05:37:50
问题 I'm just at the end of developing a quick Android App. Minor problem. What's state 4? I'm using MediaPlayer and every time I run the app I get an error stating that Media Player "start()" is first called in state 0, then state 4. Does anyone know what state 4 is? I can figure out the problem if I know the states such as state 1 and 2... Thanks, 回答1: This is from MediaPlayer.h in the Android source: enum media_player_states { MEDIA_PLAYER_STATE_ERROR = 0, MEDIA_PLAYER_IDLE = 1 << 0, MEDIA

Android SDK Media Recorder. State 4

由 醉酒当歌 提交于 2020-02-23 05:35:48
问题 I'm just at the end of developing a quick Android App. Minor problem. What's state 4? I'm using MediaPlayer and every time I run the app I get an error stating that Media Player "start()" is first called in state 0, then state 4. Does anyone know what state 4 is? I can figure out the problem if I know the states such as state 1 and 2... Thanks, 回答1: This is from MediaPlayer.h in the Android source: enum media_player_states { MEDIA_PLAYER_STATE_ERROR = 0, MEDIA_PLAYER_IDLE = 1 << 0, MEDIA
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