Пожалуйста, замените атрибут data-activates
на data-target
.
<a class='dropdown-button btn' href='#' data-target='dropdown1' data-beloworigin="true">Nested DropDown</a>
<ul id='dropdown1' class='dropdown-content dropdown-nested'>
<li><a class='dropdown-button' href='#' data-target='dropdown2' data-hover="hover" data-alignment="left">one<span class="right-triangle">▸</span></a></li>
<li><a href="#!">two</a></li>
<li><a href="#!">three</a></li>
</ul>
<ul id='dropdown2' class='dropdown-content dropdown-nested'>
<li><a href="#!">one</a></li>
<li><a class='dropdown-button' href="#" data-target="dropdown3" data-hover="hover" data-alignment="left">two<span class="right-triangle">▸</span></a></li>
<li><a href="#!">three</a></li>
</ul>
<ul id='dropdown3' class='dropdown-content'>
<li><a href="#!">three</a></li>
<li><a href="#!">four</a></li>
<li><a href="#!">five</a></li>
<li><a href="#!">six</a></li>
</ul>
Материализация изменила этот атрибут в версии 1.0.
Посмотрите на Materialise Dropdown Doc .