An event emitter is a platform for triggering and listening for events.
An event emitter is a platform for triggering and listening for events. Different libraries offer different implementations and for different purposes.
Questions tagged [eventemitter]
960 questions
17
votes
7 answers
Javascript eventemitter multiple events once
I'm using node's eventemitter though other event library suggestions are welcomed.
I want to run a function once if several events are fired. Multiple events should be listened to, but all of them are removed if any one of the events fires.…
Harry
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16
votes
1 answer
Nodejs: use eventEmitter object globally
Lets say I have 3 exposed functions: user, posts, articles
all of which needs to emit messages to a file called mediator where all of the events are set.
Currently I'm have trouble doing so
In the mediator file i have something like so:
var…
user240993
15
votes
3 answers
TypeError: instance[output.propName].subscribe is not a function
I'm trying to emit a event from child to parent component.
Parent:
parent.ts
onChangeUpload(event){
console.log('event');
console.log(event);
}
user3516604
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15
votes
4 answers
Angular 4: `ExpressionChangedAfterItHasBeenCheckedError: Expression has changed after it was checked
Every EventEmiiter in my child module gives this error and I can't find a fix for this.
ExpressionChangedAfterItHasBeenCheckedError: Expression has changed after it was checked. Previous value: 'true'. Current value: 'false'.
This is what triggers…
Nicolas
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14
votes
5 answers
Angular Two-Way Data Binding and Watching for Changes in Parent Component
It seems there is no way to watch changes in the parent component when using two-way data binding.
I have a custom input component for collecting a tag list. Two-way data binding is setup and working between this component and its parent.
// the…
Ben Racicot
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14
votes
2 answers
Using async in event emitter
I am being challenged trying to make an async call inside an event.
Here's the code from Nodemailer - I've added the line where I need to make an async call:
let transporter = nodemailer.createTransport({
SES: new aws.SES({
apiVersion:…
cyberwombat
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14
votes
5 answers
NodeJS wait for callback to finish on event emit
I have and application written in NodeJS with Express and am attempting to use EventEmitter to create a kind of plugin architecture with plugins hooking into the main code by listening to emitted events.
My problem comes when a plugin function makes…
Stuart
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13
votes
2 answers
Angular 6 - MatDialog - EventEmitter - share object to parent component from MatDialog
Right now able to communicate between two components. but don't know how to pass user (selected) entered value as Object via event emitter from MatDialog component to the parent component. Here I want to pass selected option value and text area…
Mr. Learner
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13
votes
1 answer
Angular ObjectUnsubscribedError while resubscribe
I'm getting the following error while trying to subscribe in the second time to an EventEmitter after that ngOnDestroy was invoked and called unsubscribe:
ngOnInit() {
this.route.params.subscribe(params => {
…
Or Yaacov
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13
votes
3 answers
Detect change in child component's variable triggered by parent angular 2
I have 2 files. app.ts and Child.ts
I am sending a variable from app to child and I want to detect any change in the variable and show data accordingly. I am not able to detect changes in a variable.
Any Help? I have attached Plunker Link and I have…
amansoni211
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13
votes
3 answers
Angular2 EventEmitter and preventDefault()
Is there a way in Angular2 to somehow prevent the default for events using the EventEmitter?
I have the following scenario:
import {Component, Output, EventEmitter} from 'angular2/core'
@Component({
selector: 'my-component',
template: `
seraph
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12
votes
2 answers
What are the differences between EventEmitter, EventTarget and EventDispatcher
I'm trying to learn implementations of Observer Pattern.
EventEmitter/EventTarget/EventDispatcher are one implementation of Observer Pattern but I wonder the differences between these three.
Any help would be appreciated?
uzay95
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12
votes
1 answer
how to resolve a react native EventEmitterListener warning
I am using a event emitter to communicate between a map component and the toolbar. Note* I am using this same code in other parts of my app without issue. The error I am getting is :
Warning: setState(...): Can only update a mounted or mounting…
texas697
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12
votes
1 answer
Golang events: EventEmitter / dispatcher for plugin architecture
In Node.js I was able to make a WordPress clone rather easily using the EventEmitter to replicate and build a hooks-system into the CMS core, which plugins could then attach to.
I now need this same level of extensibility and core isolation for my…
Dac0d3r
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11
votes
2 answers
EventEmitter in angular services, good or bad?
I was using EventEmitter and @Output in Angular services, today one of the colleagues mentioned it's not a good practice.
I found this post mentioning it's a bad practice and it seems mostly is personal opinion, and this answer is mentioning it's OK…
Reza
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