Performing Click on an ElementRef object in Angular 4 [duplicate] - html

Question

I am trying to fire click event (or any other event) on element programatically , In other word I want to know the similar features as offered by jQuery .trigger() method in angular2.
Is there any built in method to do this? ..... if not please suggest how can i do this
Consider the following code fragment
<form [ngFormModel]="imgUploadFrm"
(ngSubmit)="onSubmit(imgUploadFrm)">
<br>
<div class="input-field">
<input type="file" id="imgFile" (click)="onChange($event)" >
</div>
<button id="btnAdd" type="submit" (click)="showImageBrowseDlg()" )>Add Picture</button>
</form>
Here when user click the btnAdd it should fire the click event on imgFile

Answer 1

Angular4
Instead of
this.renderer.invokeElementMethod(
this.fileInput.nativeElement, 'dispatchEvent', [event]);
use
this.fileInput.nativeElement.dispatchEvent(event);
because invokeElementMethod won't be part of the renderer anymore.
Angular2
Use ViewChild with a template variable to get a reference to the file input, then use the Renderer to invoke dispatchEvent to fire the event:
import { Component, Renderer, ElementRef, ViewChild } from '#angular/core';
#Component({
...
template: `
...
<input #fileInput type="file" id="imgFile" (click)="onChange($event)" >
...`
})
class MyComponent {
#ViewChild('fileInput') fileInput:ElementRef;
constructor(private renderer:Renderer) {}
showImageBrowseDlg() {
// from http://stackoverflow.com/a/32010791/217408
let event = new MouseEvent('click', {bubbles: true});
this.renderer.invokeElementMethod(
this.fileInput.nativeElement, 'dispatchEvent', [event]);
}
}
Update
Since direct DOM access isn't discouraged anymore by the Angular team this simpler code can be used as well
this.fileInput.nativeElement.click()
See also https://developer.mozilla.org/en-US/docs/Web/API/EventTarget/dispatchEvent

Answer 2

I also wanted similar functionality where I have a File Input Control with display:none and a Button control where I wanted to trigger click event of File Input Control when I click on the button, below is the code to do so
<input type="button" (click)="fileInput.click()" class="btn btn-primary" value="Add From File">
<input type="file" style="display:none;" #fileInput/>
as simple as that and it's working flawlessly...

Answer 3

This worked for me:
<button #loginButton ...
and inside the controller:
#ViewChild('loginButton') loginButton;
...
this.loginButton.getNativeElement().click();

Answer 4

To get the native reference to something like an ion-input, ry using this
#ViewChild('fileInput', { read: ElementRef }) fileInput: ElementRef;
and then
this.fileInput.nativeElement.querySelector('input').click()

Answer 5

Günter Zöchbauer's answer is the right one. Just consider adding the following line:
showImageBrowseDlg() {
// from http://stackoverflow.com/a/32010791/217408
let event = new MouseEvent('click', {bubbles: true});
event.stopPropagation();
this.renderer.invokeElementMethod(
this.fileInput.nativeElement, 'dispatchEvent', [event]);
}
In my case I would get a "caught RangeError: Maximum call stack size exceeded" error if not. (I have a div card firing on click and the input file inside)

Answer 6

If you want to imitate click on the DOM element like this:
<a (click)="showLogin($event)">login</a>
and have something like this on the page:
<li ngbDropdown>
<a ngbDropdownToggle id="login-menu">
...
</a>
</li>
your function in component.ts should be like this:
showLogin(event) {
event.stopPropagation();
document.getElementById('login-menu').click();
}