Angular: How can I prevent the scrollbar from moving when navigating with the arrow keys up and down?

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I have developed a table and which I have integrated a self-created navigation. Problem is, when I scroll up and down so always moves the scrollbar with. Is there a way when I press keydown or keyup that the scrollbar does not move. I know that it is hostListener feasible. But I have not found out how to implement it. Can you help me please?

My Code:

// DIRECTIVE

 constructor(private keyboardService: KeyboardService,
              public element: ElementRef,
              private render: Renderer2) {
    this.render.setAttribute(this.element.nativeElement, 'tabindex', '0');
  }

  @HostListener('keydown', ['$event']) onKeyUp(e) {
    switch (e.keyCode) {
      case 38:
        this.keyboardService.sendMessage({ element: this.element, action: 'UP' });
        break;
      case 37:
        this.keyboardService.sendMessage({ element: this.element, action: 'LEFT' });
        break;
      case 40:
        this.keyboardService.sendMessage({ element: this.element, action: 'DOWN' });
        break;
      case 39:
        this.keyboardService.sendMessage({ element: this.element, action: 'RIGTH' });
        break;
    }
  }

// Component

/**
   * Use arrowKeys
   * @param object any
   */
  move(object) {
    const inputToArray = this.inputs.toArray();
    let index = inputToArray.findIndex((x) => x.element === object.element);
    switch (object.action) {
      case 'UP':
        index -= this.columns.length;
        break;
      case 'DOWN':
        index += this.columns.length;
        break;
      case 'LEFT':
        index--;
        break;
      case 'RIGTH':
        index++;
        break;
    }

    if (index >= 0 && index < this.inputs.length) {
      inputToArray[index].element.nativeElement.focus();
    }
  }

My StackBlitz: https://stackblitz.com/edit/stackoverflow-72056135-buytsq?file=app%2Ftable-basic-example.html

1 Answers

First Focus is here enter image description here

When I get here, I want the scrollbar to move first:

enter image description here

If the scrollbar moves after each keydown, cells with focus at the top are no longer visible properly.

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