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>
eval()
is not necessary. This will work fine:
var date = new Date(parseInt(jsonDate.substr(6)));
The substr()
function takes out the /Date(
part, and the parseInt()
function gets the integer and ignores the )/
at the end. The resulting number is passed into the Date
constructor.
I have intentionally left out the radix (the 2nd argument to parseInt
); see my comment below.
Also, I completely agree with Rory's comment: ISO-8601 dates are preferred over this old format - so this format generally shouldn't be used for new development.
For ISO-8601 formatted JSON dates, just pass the string into the Date
constructor:
var date = new Date(jsonDate); //no ugly parsing needed; full timezone support
Best Answer
By default images are loaded when they appear on the screen. If you want images to load earlier you can set threshold parameter. Setting threshold to 200 causes image to load 200 pixels before it is visible.
So in your case, how far is the first row down the page?
or something like that.