Advance Select
Phoenix uses Choices.js for advance select. Choices.js is a lightweight, configurable select box/text input plugin. Similar to Select2 and Selectize but without the jQuery dependency
Documentation for ChoicesMultiple Select Example
<label for="organizerMultiple">Multiple</label>
<select class="form-select" id="organizerMultiple" data-choices="data-choices" multiple="multiple" data-options='{"removeItemButton":true,"placeholder":true}'>
<option value="">Select organizer...</option>
<option>Massachusetts Institute of Technology</option>
<option>University of Chicago</option>
<option>GSAS Open Labs At Harvard</option>
<option>California Institute of Technology</option>
</select>
Single Select Example
<label for="organizerSingle">Single</label>
<select class="form-select" id="organizerSingle" data-choices="data-choices" data-options='{"removeItemButton":true,"placeholder":true}'>
<option value="">Select organizer...</option>
<option>Massachusetts Institute of Technology</option>
<option>University of Chicago</option>
<option>GSAS Open Labs At Harvard</option>
<option>California Institute of Technology</option>
</select>
Stylesheet
<pre><code class="language-html"><link href="vendors/choices/choices.min.css" rel="stylesheet" /></code></pre>
<link href="vendors/choices/choices.min.css" rel="stylesheet" />
Javascript
<pre><code class="language-html"><script src="vendors/choices/choices.min.js"></script></code></pre>
<script src="vendors/choices/choices.min.js"></script>