demo/src/app/components/+dropdown/demos/visibility-events/visibility-events.html
<div class="row">
<div class="col-xs-12 col-12">
<pre class="card card-block card-header mb-3" *ngFor="let message of messages">{{message}}</pre>
</div>
<div class="col-xs-12 col-12 mb-3">
<div class="btn-group"
dropdown
(onShown)="handler('onShown')"
(onHidden)="handler('onHidden')">
<button id="button-visbility" dropdownToggle type="button" class="btn btn-primary dropdown-toggle"
aria-controls="dropdown-visbility">
Button dropdown <span class="caret"></span>
</button>
<ul id="dropdown-visbility" *dropdownMenu class="dropdown-menu"
role="menu" aria-labelledby="button-visbility">
<li role="menuitem"><a class="dropdown-item" href="#">Action</a></li>
<li role="menuitem"><a class="dropdown-item" href="#">Another action</a></li>
<li role="menuitem"><a class="dropdown-item" href="#">Something else here</a></li>
</ul>
</div>
</div>
</div>