Category Archives: Jquery
In a couple of days JQuery team will release a new version of jquery (1.6.1), after the community struggled the problems of the backward compatibility in the last release (1.6) .. the new release redefine the usage and the effect of it on the DOM objects of both .attr() and .prop() ,
in this version the boolean attribute manipulation with .attr() will back as it was before the 1.6 release.
lets see an example:
<input id="mychkbox" type="checkbox" checked>
the result of the previous markup is a checked checkbox as we all know =d,
but thats the property value not the attribute value cuz the attribute “checked” is not set.
lets see the .attr() results in v.1.6:
alert($("#mychkbox").attr("checked")) // result >> "" alert($("#mychkbox").prop("checked")) // true alert(document.getElementById("mychkbox").checked") // true
thats because the attribute doesn’t change when the user change its state by clicking on it., thats fine.. but look at the following code
in the coming 1.6.1 release & prior versions than 1.6:
alert($("#mychkbox").attr("checked")) // true alert($("#mychkbox").prop("checked")) // true (in 1.6.1 only) alert(document.getElementById("mychkbox").checked") // true
in the coming release the behavior of .attr() will back as it was before 1.6 just because the sake of backward compatibility.
so it will work exactly as expected but that doesn’t mean you have to keep using attr() , switch to .prop() cuz it is more faster and oriented.
it might be confusing now what we should use for what when it comes to .prop() and .attr(), so here is the best usage as the Jquery team stated:
.prop() method should be used for boolean attributes/properties and for properties which do not exist in html (such as window.location).
All other attributes (ones you can see in the html) can and should continue to be manipulated with the
.attr() method. ”
it is expected to see Jquery 1.6.1 at the end of this week, Also you can fill up the following proposal for new features to be landed in jquery 1.7.
Today, and as you see from the blog post title 😀 , JQuery 1.6 has been released !
But this time not like 1.5 release, there is no much new features as 1.5 had (deferred obj., jqXHR.. etc)..
so what we have here with 1.6 ??
case-mapping of data- attributes:
Its just a change in the way data- attributes object properties creation, in earler versions data-max-value will create an object with a property like max-value but now with 1.6 , the object would be maxValue.. So what about backward compatibility ?!” , people must start fixing there already written code. !
new methods: .prop(), .removeProp():
Jquery added 2 new methods to its default JQuery object, those methods will work with DOM attributes, I know whats on your mind now –.attr() huh!- yeah, the .attr() used to be the only method that works with elements attributes/properties (beside .val() & other task-specific methods) , It might be confusing so lets define both first:
attribute: is the initial value shipped with the DOM element ex. <input type=text value=”initialValue”>
property: it is the dynamic value, ie. any value added by user or changed programmatically.
that means having the same code will run differently when updating to the new version. backward compatibility ?!
Here is a simple example I have made for more explanation:
=#1= open this fiddle [uses Jquery 1.5.2]
write something in the textbox, and click the “click here to test” button
you will notice that the result is same as you wrote.
in the other side:
=#2= open this fiddle [uses Jquery 1.6]
write something in the textbox, and click the “click here to test .attr()” button
you will notice that the result is the initial value of the textbox.
BUT .. If you clicked the other button which uses the new .prop() method will get you the current value of the textbox.
Finally.. this new version of jquery doesn’t have any other major new features,all other changes are bugfixes, Performance Improvements and some new methods.
you can check all new methods and changes to the API at this link.
update: my twitter timeline got something related:
After a discussion on Hacker News regarding the attr boolean changes in jQuery 1.6, we just landed a fix: http://j.mp/j0uMEb
Its good to know also that @jeresig is moving from mozilla to the famous online academy – Khan academy -.
ThankQQ for your time 🙂
Weeks ago I was enjoying my free time playing around in twitter’s response html & ajax requests =D .. I have found a “data-*” attribute in the html metadata .. It reminded me with the old days when I used to write attributes from my own mind in ASP.NET Repeater to the repeated elements. just to use it later in Jquery click handler or something.. later on I found that this is just realted to HTML5’s dataset I read about years but actually I forgot it, horrible memory !
may be writing a couple of lines here won’t let me forget it again !=)
the good part is I started digging in W3C Draft to refresh my memory and know the changes dropped to it.
//so lets talk a little bit about it !
lets write some markup to play around with:
<div id="container"> <span data-color="black">Samsung 23' LCD</span> <span data-color="silver">BenQ 19' LCD</span> </div>
Now If you are familiar with simple DOM methods you will know that its simply possible to access these custom attributes with getAttribute() and change the values of it by setAttribute()
var target = document.getElementsByTagName("span"); alert(target.getAttribute("data-color")); //black target.setAttribute("data-color", "blue"); alert(target.getAttribute("data-color")); //blue
Till now we have nothing new, only a couple of “hand-made” attributes and normal getAttribute & setAttribute Methods..
its time now to look at HTML5 related API
HTML5 provide a new property called dataset that returns DOMStringMap (name-value pairs object)
See the highlighted lines:
var target = document.getElementsByTagName("span"); alert(target.getAttribute("data-color")); //black target.setAttribute("data-color", "blue"); alert(target.getAttribute("data-color")); //blue alert(target.dataset.color); // blue target.dataset.color = "red"; alert(target.dataset.color); // red
the dataset property gives you an access to the custom attributes you have made in the markup, the keys inside the dataset object doesn’t have “data-” part so “data-ballSize” would be “dataset.ballSize”.
Jquery data-* support:
We already know the .DATA() method in Jquery (added with V.1.2.3 -2008) .. a couple of months ago Jquery added support for HTML5’s dataset, lets see an example for that.
var target = $("span:first"); var myData = target.data; alert(myData.color); //black
myData will have All values of inserted in any data- attribute as JSON Object.
or you can directly get the values and use it. Like..
var target = $("span:first"); var myValue = target.data("color"); alert(myValue); //black
ThankQ for reading, Hope you enjoyed it.