I need to create an interactive Facebook Tab for a client, similar to this:
http://www.facebook.com/#!/knnktr.
The application has a number of slides, which are basically images that will scroll left/right as the visitor clicks on two arrows on either side of the displayed image.
I could do this in Flash, but I could also attempt doing this with JavaScript.
Now, I understand that Facebook's APIs often change, and iframe's are currently not an option.
What is the best/correct way to achieve this. Should I stick with the Static FBML? If we have an option to use JavaScript, we'll prefer that above Flash. The question is, does the Static FBML limit the ability to perform some JavaScript calls.
I need to respond to mouse clicks, and I also need to be able to make remote AJAX requests to our server.
If you're building a tab, FBML/FBJS are your only option. The official FB docs for FBJS are pretty good: http://developers.facebook.com/docs/fbjs/
A couple caveats about FBJS:
They rewrite your Javascript to only allow limited functionality. If you're used to a nice Javascript lib like jQuery you're out of luck.
You can't use external js includes, the Javascript must be in the same page
Take a look at the event, animate and AJAX sections in the docs. Taking a quick look at your example I don't see anything you couldn't do with FBJS.
Related
I’m developing a Firefox addon and I would like to use facebook sdk in it. One of the features that I like to use is the callback that is triggered when a like button is pressed. In detail I mean this one:
FB.Event.subscribe('edge.create', function() {dump("like pressed"); });
Currently I’m doing it this way. I open a layer in the current window with an iframe. That iframe contains the facebook api + the features that I would like to use. My problem is that I can’t call my addons functions from the inside of that iframe. What I would like to do would be something like:
FB.Event.subscribe('edge.create', function() {fbClass.like(); });
In my mind I’ve one idea. I think to make it safe it would be ok to create an empty hidden div container in that iframe, attach an eventlistener to it and fill it with json. Then use firefox safe json loader to receive it.
Any other idea how I could accomplish that one without creating a security issue?
I tried porting the FB api to FF but it leaded into a waste of time. Sure I got some features work but it’s that complex to debug it and in case if the api changes I would have to do it again. So I think the iframe way would be a much better one.
I would suggest to you that use the Add-on SDK makes this task probably easier. You could add your code to the page using PageMod and from the content script calls your addon's function using postMessage. This also helps to you decoupled the content code from the addon code.
The setup: I have a Blogger blog set up on a domain name as blog.mydomain.com. The main site site at mydomain.com is running Umbraco CMS.
The problem: I need to have the navigation from the CMS transported to Blogger somehow, so that making a change on the main website doesn't require the extra step of modifying the navigation inside Blogger.
Generating the navigation data on the CMS side in what ever format it needs to be (XML, unordered list, JSON, etc) is not a problem. The problem is getting the data from Umbraco to Blogger after it is generated.
I'm not yet willing to use Javascript, as this would seriously impair the website for users browsing without Javascript. (Too bad because AJAX would be a very workable solution.)
I've tossed around the idea of using an iFrame. How would this work for a navigation system including sub-menus? Creating and deleting multiple iframes is out of the picture, since I don't want to use Javascript. I could use one large iframe to allow for the sub-menus, but then it would cover content at the top of the content area, rendering it unclickable.
I'm thinking about how you could do this, but while I do - in this day-and-age javascript has become very common. Most users are going to have it, and those with it disabled really shouldn't be on the web. Is this the only reason you don't want to use javascript? Around 2% according to YDN have js disabled, and that's lower from other countries. As time goes on that 2% should get lower, I don't see that as an issue. However if you absolutely can't use javascript, I'll keep thinking. I might have an idea, I'll need to test it though.
It's not possible to use IFrame, cause of same origin policy. Both sites are on different domains, when user click menu item inside IFrame, there is no way to call parent window.
There are few ways how this can be done.
1) Javascript solution. Use json rpc, or another cross-domain calls. Load menu from your CMS and render it. Yes, this requires javsascript, but, seriously, show me the site, which does not use javascript.
2) Direct server communication.
Is it possible to perform http call from blogger ? If so, just perform http call to your CMS from Blogger, get data and render it.
3) Mixed flash/javascript solution. Flash can perform http call regardless of same origin policy. Get data with flash, use ExternalInterface to call Javascript function to render data.
There is no another way to do it. I suggest you to use javascript solution
You could build an HTML skeleton of empty ULs in Blogger (the max that you might need) to hold your navigation contents, and then link to an Umbraco-generated external stylesheet.
This stylesheet could fill those LIs with CSS generated content using the :before and :after pseudo-elements, and hiding unused LIs with CSS display: none.
An example of this is at: http://jsfiddle.net/5bXja/1/
This works in IE8+ so depending on your clients, this may-or-may-not be more widely supported than Javascript. Likely not. ;-)
So far what I have used with my gwt application is a simple FI, like #login, #welcome etc.
However I want to "refactor" my application in a more descriptive way, I need make it this way:
http://localhost:8080/main#login
http://localhost:8080/main#search
http://localhost:8080/profile#<username>
http://localhost:8080/api
etc.
Can I do this with GWT?
If you want to stay on the same GWT application, you'll have to use the HTML5 History API (pushState and onpopstate) instead of GWT's default History (or DefaultHistorian) implementation; which means your app would only work with browser supporting the HTML5 History API (or you'd have to provide a fallback).
This is possible with GWT, but if you don't know how to do it and/or how the HTML5 History API works, it'll cost you a lot (of time).
BTW, if you ever switch to the HTML5 History API, why keep some fragment identifiers?
The alternative is, as milan says, to split your app into smaller parts (/main, /profile, /api, etc.)
Yes, but /main and /profile are going to be separate (html) pages, so you'll have EntryPoint for each then (loading/unloading GWT modules). Is that want you want? Google's AdWords is an example (written in GWT), each tab is a separate HTML page (/dashboard/, /cm/CampaignMgmt, ...).
I have a page with 20 articles, and for each article, I have a Facebook Like Button, implemented using the tag.
Because of this, my site is greatly slowed down as Firefox makes a query in the background for each of the like button.
Is there anything I can do to reduce this load?
In my experience, all the extra IFRAMES are actually faster than using the JavaScript SDK, even though the Like icons are supposed to load asynchonously. I have a page with about 18 like buttons on it, and at least the IFRAME approach doesn't result in a perceived slowdown for users like the JS version does - the only downside is that the Like buttons "pop" into the page a little late in IFRAMES.
I assume you're using iframe to display your like buttons. Performance is the downside of using iframes. If you've got 20 iframes, then it's equivalent to loading 20 web pages (with 20 independent http requests). As browsers have connection limits per domain, it can take a while for this many iframes to load. This is especially true in older browsers, where connection limit is only 2 per domain, which means that only 2 iframes can load at a time. iframe can also have the negative side effect of blocking other downloads, which makes the problem even worse. You can read all about iframe performance problems here:
http://www.stevesouders.com/blog/2009/06/03/using-iframes-sparingly/
If possible, you may want to consider using xfbml like button instead of iframe. Unfortunately, this means that you'll need to load Facebook's JavaScript SDK, but with 20 like buttons, you should see an overall performance boost.
As an alternative, if you're not keen on the idea of xfbml, you could try a service like OpenLike: http://openlike.org/
From their docs:
A widget is created by first loading the OpenLike javascript and then calling OPENLIKE.Widget(). Multiple widgets can be embedded in the same page, each with different options.
I ended up going with something similar to this solution Lots of XFBML Facebook Like buttons are slow? with JQuery Sonar. It seems to do the trick for me. I'd prefer a single call that loads all the buttons but it's outside of my control.
If I had more time what I'd do is use the facebook API to get the count and make my own buttons (perhaps load the real button on hover if i wanted their functionality but iirc you can just call the "share" function directly). I don't currently have time to massage facebook that much so this is a sorta makeshift hack that I don't think has too many downsides and it seems to be used by a number of different sites.
I've just noticed that the long, convoluted Facebook URLs that we're used to now look like this:
http://www.facebook.com/example.profile#!/pages/Another-Page/123456789012345
As far as I can recall, earlier this year it was just a normal URL-fragment-like string (starting with #), without the exclamation mark. But now it's a shebang or hashbang (#!), which I've previously only seen in shell scripts and Perl scripts.
The new Twitter URLs now also feature the #! symbols. A Twitter profile URL, for example, now looks like this:
http://twitter.com/#!/BoltClock
Does #! now play some special role in URLs, like for a certain Ajax framework or something since the new Facebook and Twitter interfaces are now largely Ajaxified?
Would using this in my URLs benefit my Web application in any way?
This technique is now deprecated.
This used to tell Google how to index the page.
https://developers.google.com/webmasters/ajax-crawling/
This technique has mostly been supplanted by the ability to use the JavaScript History API that was introduced alongside HTML5. For a URL like www.example.com/ajax.html#!key=value, Google will check the URL www.example.com/ajax.html?_escaped_fragment_=key=value to fetch a non-AJAX version of the contents.
The octothorpe/number-sign/hashmark has a special significance in an URL, it normally identifies the name of a section of a document. The precise term is that the text following the hash is the anchor portion of an URL. If you use Wikipedia, you will see that most pages have a table of contents and you can jump to sections within the document with an anchor, such as:
https://en.wikipedia.org/wiki/Alan_Turing#Early_computers_and_the_Turing_test
https://en.wikipedia.org/wiki/Alan_Turing identifies the page and Early_computers_and_the_Turing_test is the anchor. The reason that Facebook and other Javascript-driven applications (like my own Wood & Stones) use anchors is that they want to make pages bookmarkable (as suggested by a comment on that answer) or support the back button without reloading the entire page from the server.
In order to support bookmarking and the back button, you need to change the URL. However, if you change the page portion (with something like window.location = 'http://raganwald.com';) to a different URL or without specifying an anchor, the browser will load the entire page from the URL. Try this in Firebug or Safari's Javascript console. Load http://minimal-github.gilesb.com/raganwald. Now in the Javascript console, type:
window.location = 'http://minimal-github.gilesb.com/raganwald';
You will see the page refresh from the server. Now type:
window.location = 'http://minimal-github.gilesb.com/raganwald#try_this';
Aha! No page refresh! Type:
window.location = 'http://minimal-github.gilesb.com/raganwald#and_this';
Still no refresh. Use the back button to see that these URLs are in the browser history. The browser notices that we are on the same page but just changing the anchor, so it doesn't reload. Thanks to this behaviour, we can have a single Javascript application that appears to the browser to be on one 'page' but to have many bookmarkable sections that respect the back button. The application must change the anchor when a user enters different 'states', and likewise if a user uses the back button or a bookmark or a link to load the application with an anchor included, the application must restore the appropriate state.
So there you have it: Anchors provide Javascript programmers with a mechanism for making bookmarkable, indexable, and back-button-friendly applications. This technique has a name: It is a Single Page Interface.
p.s. There is a fourth benefit to this technique: Loading page content through AJAX and then injecting it into the current DOM can be much faster than loading a new page. In addition to the speed increase, further tricks like loading certain portions in the background can be performed under the programmer's control.
p.p.s. Given all of that, the 'bang' or exclamation mark is a further hint to Google's web crawler that the exact same page can be loaded from the server at a slightly different URL. See Ajax Crawling. Another technique is to make each link point to a server-accessible URL and then use unobtrusive Javascript to change it into an SPI with an anchor.
Here's the key link again: The Single Page Interface Manifesto
First of all: I'm the author of the The Single Page Interface Manifesto cited by raganwald
As raganwald has explained very well, the most important aspect of the Single Page Interface (SPI) approach used in FaceBook and Twitter is the use of hash # in URLs
The character ! is added only for Google purposes, this notation is a Google "standard" for crawling web sites intensive on AJAX (in the extreme Single Page Interface web sites). When Google's crawler finds an URL with #! it knows that an alternative conventional URL exists providing the same page "state" but in this case on load time.
In spite of #! combination is very interesting for SEO, is only supported by Google (as far I know), with some JavaScript tricks you can build SPI web sites SEO compatible for any web crawler (Yahoo, Bing...).
The SPI Manifesto and demos do not use Google's format of ! in hashes, this notation could be easily added and SPI crawling could be even easier (UPDATE: now ! notation is used and remains compatible with other search engines).
Take a look to this tutorial, is an example of a simple ItsNat SPI site but you can pick some ideas for other frameworks, this example is SEO compatible for any web crawler.
The hard problem is to generate any (or selected) "AJAX page state" as plain HTML for SEO, in ItsNat is very easy and automatic, the same site is in the same time SPI or page based for SEO (or when JavaScript is disabled for accessibility). With other web frameworks you can ever follow the double site approach, one site is SPI based and another page based for SEO, for instance Twitter uses this "double site" technique.
I would be very careful if you are considering adopting this hashbang convention.
Once you hashbang, you can’t go back. This is probably the stickiest issue. Ben’s post put forward the point that when pushState is more widely adopted then we can leave hashbangs behind and return to traditional URLs. Well, fact is, you can’t. Earlier I stated that URLs are forever, they get indexed and archived and generally kept around. To add to that, cool URLs don’t change. We don’t want to disconnect ourselves from all the valuable links to our content. If you’ve implemented hashbang URLs at any point then want to change them without breaking links the only way you can do it is by running some JavaScript on the root document of your domain. Forever. It’s in no way temporary, you are stuck with it.
You really want to use pushState instead of hashbangs, because making your URLs ugly and possibly broken -- forever -- is a colossal and permanent downside to hashbangs.
To have a good follow-up about all this, Twitter - one of the pioneers of hashbang URL's and single-page-interface - admitted that the hashbang system was slow in the long run and that they have actually started reversing the decision and returning to old-school links.
Article about this is here.
I always assumed the ! just indicated that the hash fragment that followed corresponded to a URL, with ! taking the place of the site root or domain. It could be anything, in theory, but it seems the Google AJAX Crawling API likes it this way.
The hash, of course, just indicates that no real page reload is occurring, so yes, it’s for AJAX purposes. Edit: Raganwald does a lovely job explaining this in more detail.