Angular - Focus on input with dynamic IDs on click

Question

*There are a lot of similar questions but I have not found a true duplicate that answers my question Apologies if I missed something.

I have a page with several inputs/buttons (The same component repeated) and need to focus on the correct input upon button click.

I have tried variations of elementRef, nativeElement, focusing based on the ID... but I can only get it to focus on the first one in the DOM or specific ones...

<ng-template #myTemplate let-context="context">
<input #foo [id]="'myInput'+context.id" />
<button class="btn" [id]="'btnAction'+context.id (click)="focusOnInput()"></button>
</ng-template>

Which renders like this in the DOM:

<input #foo id="myInput1" />
<button class="btn" id="btnAction1></button>

<input #foo id="myInput2" />
<button class="btn" id="btnAction2></button>

<input #foo id="myInput3" />
<button class="btn" id="btnAction3></button>

This is what I've been trying:

@ViewChild("foo") focusOnThis: ElementRef;
focusOnInput(): void {
this.focusOnThis.nativeElement.focus();
}

Desired behavior: When clicking on the button, focus on the respective input. Currently, it only focuses on the first one, or whichever ID I specify...

Answer 1

You can call foo.focus() in the button click handler. Since the scope of the template reference variable #foo is the template instance, it will refer to the sibling input element.

<ng-template #myTemplate let-context="context">
  <input #foo />
  <button class="btn" (click)="foo.focus()"></button>
</ng-template>

See this stackblitz for a demo.

---

If you need to set the focus from a method, pass foo to it as an argument:

<ng-template #myTemplate let-context="context">
  <input #foo />
  <button class="btn" (click)="focusOnInput(foo)"></button>
</ng-template>

focusOnInput(input): void {
  // Do something else here
  ...
  input.focus();
}

Answer 2

How about to use a data-attribute with id and get the input from it?

<ng-template #myTemplate let-context="context">
<input [attr.data-group]="context.id" />
<button class="btn" [attr.data-group]="context.id" (click)="focusOnInput($event)"></button>
</ng-template>

<input data-group="1" />
<button class="btn" data-group="1"></button>

<input data-group="2" />
<button class="btn" data-group="2"></button>

<input data-group="3" />
<button class="btn" data-group="3"></button>

// component constructor
constructor(
    private readonly elementRef: ElementRef,
    // ...
  ) {
    // ...
  }

focusOnInput(event: MouseEvent): void {
    const groupId = (<HTMLElement>event.target).dataset.group;
    const input = this.elementRef.nativeElement.querySelector(`input[data-group="${groupId}"]`);
    input.focus();
}