Javascript to detect whether the dropdown of a select element is visible


I have a select element in a form, and I want to display something only if the dropdown is not visible. Things I have tried:

  • Watching for click events, where odd clicks mean the dropdown is visible and even clicks mean the dropdown isn't. Misses other ways the dropdown could disappear (pressing escape, tabbing to another window), and I think this could be hard to get right cross-browser.
  • Change events, but these only are triggered when the select box's value changes.


Best Solution

here is how I would preferred to do it. focus and blur is where it is at.

        <select id="ddlBox">
            <option>Option 1</option>
            <option>Option 2</option>
            <option>Option 3</option>
        <div id="divMsg">some text or whatever goes here.</div>
<script type="text/javascript">
    window.onload = function() {
        var ddlBox = document.getElementById("ddlBox");
        var divMsg = document.getElementById("divMsg");
        if (ddlBox && divMsg) {
            ddlBox.onfocus = function() {
       = "none";
            ddlBox.onblur = function() {
       = "";
   = "";