As of jQuery 1.7 you should use jQuery.fn.on
with the selector parameter filled:
$(staticAncestors).on(eventName, dynamicChild, function() {});
Explanation:
This is called event delegation and works as followed. The event is attached to a static parent (staticAncestors
) of the element that should be handled. This jQuery handler is triggered every time the event triggers on this element or one of the descendant elements. The handler then checks if the element that triggered the event matches your selector (dynamicChild
). When there is a match then your custom handler function is executed.
Prior to this, the recommended approach was to use live()
:
$(selector).live( eventName, function(){} );
However, live()
was deprecated in 1.7 in favour of on()
, and completely removed in 1.9. The live()
signature:
$(selector).live( eventName, function(){} );
... can be replaced with the following on()
signature:
$(document).on( eventName, selector, function(){} );
For example, if your page was dynamically creating elements with the class name dosomething
you would bind the event to a parent which already exists (this is the nub of the problem here, you need something that exists to bind to, don't bind to the dynamic content), this can be (and the easiest option) is document
. Though bear in mind document
may not be the most efficient option.
$(document).on('mouseover mouseout', '.dosomething', function(){
// what you want to happen when mouseover and mouseout
// occurs on elements that match '.dosomething'
});
Any parent that exists at the time the event is bound is fine. For example
$('.buttons').on('click', 'button', function(){
// do something here
});
would apply to
<div class="buttons">
<!-- <button>s that are generated dynamically and added here -->
</div>
Webkit browsers set the height and width property after the image is loaded. Instead of using timeouts, I'd recommend using an image's onload event. Here's a quick example:
var img = $("img")[0]; // Get my img elem
var pic_real_width, pic_real_height;
$("<img/>") // Make in memory copy of image to avoid css issues
.attr("src", $(img).attr("src"))
.load(function() {
pic_real_width = this.width; // Note: $(this).width() will not
pic_real_height = this.height; // work for in memory images.
});
To avoid any of the effects CSS might have on the image's dimensions, the code above makes an in memory copy of the image. This is a very clever solution suggested by FDisk.
You can also use the naturalHeight
and naturalWidth
HTML5 attributes.
Best Answer
Chrome doesn't support cookies for local files (or, like Peter Lyons mentioned, localhost*) unless you start it with the --enable-file-cookies flag. You can read a discussion about it at http://code.google.com/p/chromium/issues/detail?id=535.
*Chrome does support cookies if you use the local IP address (127.0.0.1) directly. so in the localhost case, that could be an easier workaround.