angular2 manually firing click event on particular

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

This worked for me:

<button #loginButton ...

and inside the controller:

@ViewChild('loginButton') loginButton;
...
this.loginButton.getNativeElement().click();

Answer 2

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 3

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 4

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();
}

Answer 5

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...