Event detect when css property changed using Jquery


Is there a way to detect if the "display" css property of an element is changed (to whether none or block or inline-block...)? if not, any plugin? Thanks

Note

Mutation events have been deprecated since this post was written, and may not be supported by all browsers. Instead, use a mutation observer.

Yes you can. DOM L2 Events module defines mutation events; one of them - DOMAttrModified is the one you need. Granted, these are not widely implemented, but are supported in at least Gecko and Opera browsers.

Try something along these lines:

document.documentElement.addEventListener('DOMAttrModified', function(e){
  if (e.attrName === 'style') {
    console.log('prevValue: ' + e.prevValue, 'newValue: ' + e.newValue);
  }
}, false);

document.documentElement.style.display = 'block';

You can also try utilizing IE's "propertychange" event as a replacement to DOMAttrModified. It should allow to detect style changes reliably.


You can use attrchange jQuery plugin. The main function of the plugin is to bind a listener function on attribute change of HTML elements.

Code sample:

$("#myDiv").attrchange({
    trackValues: true, // set to true so that the event object is updated with old & new values
    callback: function(evnt) {
        if(evnt.attributeName == "display") { // which attribute you want to watch for changes
            if(evnt.newValue.search(/inline/i) == -1) {

                // your code to execute goes here...
            }
        }
    }
});

You can use jQuery's css function to test the CSS properties, eg. if ($('node').css('display') == 'block').

Colin is right, that there is no explicit event that gets fired when a specific CSS property gets changed. But you may be able to flip it around, and trigger an event that sets the display, and whatever else.

Also consider using adding CSS classes to get the behavior you want. Often you can add a class to a containing element, and use CSS to affect all elements. I often slap a class onto the body element to indicate that an AJAX response is pending. Then I can use CSS selectors to get the display I want.

Not sure if this is what you're looking for.


For properties for which css transition will affect, can use transitionend event, example for z-index:

$(".observed-element").on("webkitTransitionEnd transitionend", function(e) {
  console.log("end", e);
  alert("z-index changed");
});

$(".changeButton").on("click", function() {
  console.log("click");
  document.querySelector(".observed-element").style.zIndex = (Math.random() * 1000) | 0;
});
.observed-element {
  transition: z-index 1ms;
  -webkit-transition: z-index 1ms;
}
div {
  width: 100px;
  height: 100px;
  border: 1px solid;
  position: absolute;
}
<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script>
<button class="changeButton">change z-index</button>
<div class="observed-element"></div>


You can't. CSS does not support "events". Dare I ask what you need it for? Check out this post here on SO. I can't think of a reason why you would want to hook up an event to a style change. I'm assuming here that the style change is triggered somwhere else by a piece of javascript. Why not add extra logic there?