Custom Event emitter/consumers in Browser Javascript outside DOM


Custom Event emitter/consumers in Browser Javascript outside DOM



Currently I have the following structure, an Object WebsocketService and multiple FrontendControllers.


WebsocketService


FrontendController



The WebsocketService listens on a websocket (duh) and updates the internal application state. This means in some cases the front end must be updated with new values.


WebsocketService



To keep my UI code and the application logic nicely seperated I envision a design where the FrontendControllers can subscribe to events emitted the WebsocketService and very likely other Services later on.


FrontendController


WebsocketService



I have read the documentation for Creating and triggering events on MDN. But all of that is very DOM centric. My WebsocketService obviously doesn't have an addEventListener function.


WebsocketService


addEventListener



I would prefer to not use 3th-party libraries. A hack that comes to mind is simply have an id="events" DOM Node somewhere and having everyone subscribe to that. Then dispatchEvents on that Element and have the FrontendControllers decide that they care about.


id="events"


dispatchEvent


FrontendController



Of course I could also implement my own infrastructure for all this, but I'd also prefer to avoid that, because I'm lazy.



What is the clean way to do this? Or is there a much better solution to decouple my application logic and frontend in plain old javascript?



This question has not received enough attention.









By clicking "Post Your Answer", you acknowledge that you have read our updated terms of service, privacy policy and cookie policy, and that your continued use of the website is subject to these policies.

Comments

Post a Comment

Popular posts from this blog

paramiko-expect timeout is happening after executing the command

paramiko-expect timeout is happening after executing the command Can someone help me why timeout is happening after executing the command .I am trying to SSH to a machine and execute a command.I want to store the result of the executed command . I have referred paramiko-timeout but i didn't get my expected result. import traceback try: import paramiko except ImportError: raise Exception("Please install paramiko , pip install paramiko") import pexpect from paramiko_expect import SSHClientInteraction def main(): HOSTNAME = "minion5.net" USERNAME = "root" PASSWORD = "help@432" PROMPT = "root@*:~$s+" try: client = paramiko.SSHClient() client.load_system_host_keys() client.set_missing_host_key_policy(paramiko.AutoAddPolicy()) client.connect(hostname=HOSTNAME, username=USERNAME, password=PASSWORD) with SSHClientInteraction(client, timeout=20, display=True) as interact: ...
Read more

Possible Unhandled Promise Rejection (id: 0): ReferenceError: user is not defined ReferenceError: user is not defined

Possible Unhandled Promise Rejection (id: 0): ReferenceError: user is not defined ReferenceError: user is not defined I have stored data user with AsyncStorage when i want to get it, it renders null in alert and the above error in the console,i don't know why. I can not see why it returns null with user but token all is well profile.js : import React, {Component} from 'react'; import { StyleSheet, Text, View, Image, TouchableOpacity,AsyncStorage} from 'react-native'; import { Container, Content, Header,Right, Left, Body} from 'native- base'; import Feather from 'react-native-vector-icons/Feather'; export default class Profile extends Component { constructor (props){ super(props); this.state = { user: null } } componentDidMount(){ this.fetchData(); } fetchData = async() =>{ let username = await AsyncStorage.getItem('user') this.setState({ user: username }) ...
Read more

Opening a url is failing in Swift

Opening a url is failing in Swift breakpointing inside the callback and logging success shows false. I added itms-apps to my plist: LSApplicationQueriesSchemes and put this in my app delegate: func application(_ app: UIApplication, open url: URL, options: [UIApplicationOpenURLOptionsKey : Any] = [:]) -> Bool { return true } func moreTapped() { let url = NSURL(string: "itms-apps://itunes.com/developer/quantum-productions/id979315877") if #available(iOS 10.0, *) { UIApplication.shared.open(url! as URL, options: [:], completionHandler: {(success: Bool) in }) } else { UIApplication.shared.openURL(url! as URL) } } Are you testing on a real device? – rmaddy Jun 21 at 23:57 I try on a device, get "Cannot Connect to App Store". Device is online ...
Read more