JSFiddle - React, Tailwind, and code Playground

by Norlihazmey Ghazali

HTML

<div class="panel-heading">
  <select id="loading-by-tag">
    <option value="" disabled selected> -- Select Subject --</option>
    <option value="value1">Selection 1</option>
    <option value="value2">Selection 2</option>
  </select>

  <select id="loading-by-sub-tag">
    <option value="" disabled selected> -- Select Subject --</option>
    <option value="value1">Selection 1</option>
    <option value="value2">Selection 2</option>
  </select> 
  
</div>

JavaScript

$('select').change(function() {
	var m = $(this).siblings('select').addBack();
  var n = m.filter(function(){
		return $(this).val() == null && $(this)
  });  
  if ( !n.length ) alert('both selected')
})