Click me to switch icon from fa-angle-up to fa-angle-down.
Initially displaying the fa-angle-up icon, clicking it will change it to fa-angle-down.
<div class="col text-right">
<div ngbDropdown placement="top-right" class="d-inline-block">
<div id="dropdownBasic2" ngbDropdownToggle>
<i class="fa fa-angle-up fa-5x"></i>
</div>
<i class="fa fa-angle-down fa-5x"></i> <!--display this on click-->
<div ngbDropdownMenu aria-labelledby="dropdownBasic2">
<button class="dropdown-item">Action - 1</button>
<button class="dropdown-item">Another Action</button>
<button class="dropdown-item">Something else is here</button>
</div>
</div>
</div>
</div>