valor-software/ng2-bootstrap

<div class="btn-group" dropdown>
  <button id="button-config" dropdownToggle type="button" class="btn btn-primary dropdown-toggle"
          aria-controls="dropdown-config">
    Button dropdown <span class="caret"></span>
  </button>
  <ul id="dropdown-config" *dropdownMenu class="dropdown-menu"
      role="menu" aria-labelledby="button-config">
    <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>