How to detect DIV's dimension changed?

William Choi picture William Choi · Jun 27, 2011 · Viewed 390.4k times · Source

I've the following sample html, there is a DIV which has 100% width. It contains some elements. While performing windows re-sizing, the inner elements may be re-positioned, and the dimension of the div may change. I'm asking if it is possible to hook the div's dimension change event? and How to do that? I currently bind the callback function to the jQuery resize event on the target DIV, however, no console log is outputted, see below:

Before Resize enter image description here

<html>
<head>
    <script type="text/javascript" language="javascript" src="http://code.jquery.com/jquery-1.6.1.min.js"></script>
    <script type="text/javascript" language="javascript">
            $('#test_div').bind('resize', function(){
                console.log('resized');
            });
    </script>
</head>
<body>
    <div id="test_div" style="width: 100%; min-height: 30px; border: 1px dashed pink;">
        <input type="button" value="button 1" />
        <input type="button" value="button 2" />
        <input type="button" value="button 3" />
    </div>
</body>
</html>

Answer

Daniel Herr picture Daniel Herr · Sep 4, 2016

A new standard for this is the Resize Observer api, available in Chrome 64.

function outputsize() {
 width.value = textbox.offsetWidth
 height.value = textbox.offsetHeight
}
outputsize()

new ResizeObserver(outputsize).observe(textbox)
Width: <output id="width">0</output><br>
Height: <output id="height">0</output><br>
<textarea id="textbox">Resize me</textarea><br>

Resize Observer

Spec: https://wicg.github.io/ResizeObserver

Polyfills: https://github.com/WICG/ResizeObserver/issues/3

Firefox Issue: https://bugzil.la/1272409

Safari Issue: http://wkb.ug/157743

Current Support: http://caniuse.com/#feat=resizeobserver