i'm Trying to implement a web application and it's like a mix of some of twitter , facebook , pinterest features so the app is highly dependent on asynchronous calls to the server , any help with that i just want to know whether to use just ajax or there is some other magic do do better .
you will need ajax to hit server side code. And will be in need soon when you need to call javascript from serveide code ie reverse ajax.
By using DWR framework you can acomplish both of them.
Other wise using jquery's ajax functionality will be a great help.
Related
How can I decide if a website is using Ajax technology? What are the characteristics that I should I look in the website to tell it is an ajax application?
Search the javascript for XMLHttpRequest. Beyond that, the working definition of Ajax is rather too broad to look for, say, specific behaviours.
You can just look into the javascript source code and search for .ajax, .post and .get . If you find any of these they use ajax technologies.
You can also look at the network requests a page sends, if the page sends requests after loading the full page without you seeing it refreshing it probably uses ajax.
There's nothing special about websites using AJAX, it just means they make an asynchronous call to the server at some point. You can't know for certain that the website will make such a call unless you run it.
Is it possible to load part(content) of an angularjs app using ajax? if it is, please direct me to some topics i could study to succesfully do it.
You can't. AngularJS is a Single-Page Application framework, which means everything should be loaded once, then AngularJS taking care of changing routing, views, etc.
The only possibility not to load everything is when the server is in charge of rendering views, thus using AngularJS not as SPA, but just for its templating abilities and component abilities (directives).
So you can't load partially using ajax.
I have been looking at Hulu's new website and I am very impressed from a developer's standpoint (as well as a designer's).
I have found that, unless you switch between http/https, you are served content entirely from json requests. That is a HUGE feat to have this level of ajax while maintaining browse back button support as well as allowing each url to be visited directly.
I want to create a website like this as a learning experience. Is there any type of framework out there that can give me this kind of support?
I was thinking I could...
leverage jQuery
use clientside MVVM frameworks like KnockoutJS?
use ASP.NET MVC content negotiation to serve html or json determined by an accept header.
using the same codebase.
use the same template for client side and server side rendering
provide ways to update pagetitle/meta tags/etc.
Ajax forms/widgets/etc would still be used, by I am thinking about page level ajax using json and client side templates.
What do you think? Any frameworks out there? Any patterns I could follow?
It is always best to first build a website without AJAX support, then add AJAX on top of that. Doing this means that:
users without javascript can already access your website
users can already visit any URL directly.
Adding AJAX support can be accomplished by various javascript libraries. So that you can render json content, you will want to look at javascript templating. You will want to use javascript templating even on your server side for when you add AJAX support (file extension .ejs). This will probably require some appropriate libraries to run javascript on the server.
When you add AJAX support, you will want to use the "History.js" library for browser back/forward/history support.
Make no mistake. This is a HUGE project (unless your website only has a few pages). So it is going to take a LONG time to add all the AJAX support to the best possible standard.
to answer your bullet point about using the same template server side as well as client side: check outdust. It was originally developed by akdubya, but has since been adopted and enhanced by linkedin. They use it to render templates on their mobile app client side. Personally I've used it on the server side and it works great.
What do i need to do for putting ajax functionality to my project.
What tool kit do i need to download or how can i integrate that .
and do i really need to do something for putting update panel for my project?
One method for AJAX enabling your ASP sites is using the AJAX control toolkit (http://www.asp.net/ajax/ajaxcontroltoolkit/samples/) which provides some AJAX functionality using ASP controls that should be familiar to a novice Dot Net developer. AJAX Control Toolkit is a DLL you add to your solution just like other controls. There is then markup for use in the ASP.NET pages.
For more customized and advanced AJAX features, your best bet is using JQuery (http://jquery.com/) and create *.asmx Web Services. JQuery includes a $.ajax() call that will communicate to ASP.NET Web Services using JSON. This SO page may help - Calling ASMX from jQuery and this Encosia blog entry may help - http://encosia.com/2008/03/27/using-jquery-to-consume-aspnet-json-web-services/. JQuery is a library of JavaScript files that you download, include in your page, and call into using your own JavaScript files.
I would also recommend that you read the wikipedia entry for AJAX (http://en.wikipedia.org/wiki/Ajax_(programming)) and familiarize yourself with the related technologies.
I think you need to provide a lot more information before we can give youa definitive answer.
Ajax is simply using Javascript to request a webpage - same as a user clicking on a link - except that JavaScript gets the contents of the page requested instead of showing it to the user.
This allows you to request data within JavaScript without refreshing the page.
As you mentioned UpdatePanel, I'm assuming you're using ASP.Net - In which case, .Net 2.0 didn't include AJAX and you needed to get some additional installs to make it work. 3.5 and later includes it natively.
If you're just starting to get into the whole area, I suggest you do some reading about how AJAX works behind the scenes before trying to use it - Understanding what its doing will save you a LOT of headaches later.
FWIW you don't actually need ANYTHING special to make AJAX work - you can write it yourself entirely in JavaScript (I've done this far too many times). As mentioned in Doug's answer, JQuery is fantastic and is worth using even without the AJAX functionality.
If, however, you want to use UpdatePanels and AJAX, the easiest option is .Net 3.5 or later (Visual Studio 2008 or later)
In my opinion, jQuery has the best AJAX functionality and is easy to learn and use. It's got great documentation and there are lots of tutorials and examples -- I love it.
I am trying to find the optimal architecture for an ajax-heavy Django application I'm currently building. I'd like to keep a consistent way of doing forms, validation, fetching data, JSON message format but find it exceedingly hard to find a solution that can be used consistently.
Can someone point me in the right direction or share their view on best practice?
I make everything as normal views which display normally in the browser. That includes all the replies to AJAX requests (sub pages).
When I want to make bits of the site more dynamic I then use jQuery to do the AJAX, or in this case AJAH and just load the contents of one of the divs in the sub page into the requesting page.
This technique works really well - it is very easy to debug the sub pages as they are just normal pages, and jQuery makes your life very easy using these as part of an AJA[XH]ed page.
For all the answers to this, I can't believe no one's mentioned django-piston yet. It's mainly promoted for use in building REST APIs, but it can output JSON (which jQuery, among others, can consume) and works just like views in that you can do anything with a request, making it a great option for implementing AJAX interactions (or AJAJ [JSON], AJAH, etc whatever). It also supports form validation.
I can't think of any standard way to insert ajax into a Django application, but you can have a look to this tutorial.
You will also find more details on django's page about Ajax
Two weeks ago I made a write up how I implement sub-templates to use them in "normal" and "ajax" request (for Django it is the same). Maybe it is helpful for you.
+1 to Nick for pages displaying normally in the browser. That seems to be the best starting point.
The problem with the simplest AJAX approaches, such as Nick and vikingosegundo propose, is that you'll have to rely on the innerHTML property in your Javascript. This is the only way to dump the new HTML sent in the JSON. Some would consider this a Bad Thing.
Unfortunately I'm not aware of a standard way to replicate the display of forms using Javascript that matches the Django rendering. My approach (that I'm still working on) is to subclass the Django Form class so it outputs bits of Javascript along with the HTML from as_p() etc. These then replicate the form my manipulating the DOM.
From experience I know that managing an application where you generate the HTML on the server side and just "insert" it into your pages, becomes a nightmare. It is also impossible to test using the Django test framework. If you're using Selenium or a similar tool, it's ok, but you need to wait for the ajax request to go return so you need tons of sleeps in your test script, which may slow down your test suite.
If the purpose of using the Ajax technique is to create a good user interface, I would recommend going all in, like the GMail interface, and doing everything in the browser with JavaScript. I have written several apps like this using nothing but jQuery, state machines for managing UI state and JSON with ReST on the backend. Django, IMHO, is a perfect match for the backend in this case. There are even third party software for generating a ReST-interface to your models, which I've never used myself, but as far as I know they are great at the simple things, but you of course still need to do your own business logic.
With this approach, you do run into the problem of duplicating code in the JS and in your backend, such as form handling, validation, etc. I have been thinking about solving this with generating structured information about the forms and validation logic which I can use in JS. This could be compiled at deploy-time and be loaded as any other JS file.
Also, avoid XML. The browsers are slow at parsing it, it is a pain to generate and a pain to work with in the browser. Use JSON.
Im currently testing:
jQuery & backbone.js client-side
django-piston (intermediate layer)
Will write later my findings on my blog http://blog.sserrano.com