I have a HTML list of about 500 items and a "filter" box above it. I started by using jQuery to filter the list when I typed a letter (timing code added later): $('#filter').keyup( function() { var jqStart = (new Date).getTime(); var search = $(this).val().toLowerCase(); var $list = $('ul.ablist > li'); $list.each( function() { if ( $(this).text().toLowerCase().indexOf(search) === -1 ) $(this).hide(); else $(this).show(); } ); console.log('Time: ' + ((new Date).getTime() - jqStart)); } ); However, there was a couple of seconds delay after typing each letter (particularly the first letter). So I thought it may be slightly quicker if I used plain Javascript (I read recently that jQuery's each function is particularly slow). Here's my JS equivalent: document.getElementById('filter').addEventListener( 'keyup', function () { var jsStart = (new Date).getTime()...
if (top === self) { not in a frame } else { in a frame }
ReplyDeletetop and self are both window objects (along with parent), so you're seeing if your window is the top window.
RoBorg is correct, but I wanted to add a side note.
ReplyDeleteIn IE7/IE8 when Microsoft added Tabs to their browser they broke one thing that will cause havoc with your JS if you are not careful.
Imagine this page layout:
MainPage.html
IframedPage1.html (named "foo")
IframedPage2.html (named "bar")
IframedPage3.html (named "baz")
Now in frame "baz" you click a link (no target, loads in the "baz" frame) it works fine.
If the page that gets loaded, lets call it special.html, uses JS to check if "it" has a parent frame named "bar" it will return true (expected).
Now lets say that the special.html page when it loads, checks the parent frame (for existence and its name, and if it is "bar" it reloads itself in the bar frame. e.g.
if(window.parent && window.parent.name == 'bar'){
window.parent.location = self.location;
}
So far so good. Now comes the bug.
Lets say instead of clicking on the original link like normal, and loading the special.html page in the "baz" frame, you middle-clicked it or chose to open it in a new Tab.
When that new tab loads (with no parent frames at all!) IE will enter an endless loop of page loading! because IE "copies over" the frame structure in JavaScript such that the new tab DOES have a parent, and that parent HAS the name "bar".
The good news, is that checking:
if(self == top){
//this returns true!
}
in that new tab does return true, and thus you can test for this odd condition.
The accepted answer didn't work for me inside the content script of a Firefox 6.0 Extension (Addon-SDK 1.0): Firefox executes the content script in each: the top-level window and in all iframes.
ReplyDeleteInside the content script I get the following results:
(window !== window.top) : false
(window.self !== window.top) : true
The strange thing about this output is that it's always the same regardless whether the code is run inside an iframe or the top-level window.
On the other hand Google Chrome seems to execute my content script only once within the top-level window, so the above wouldn't work at all.
What finally worked for me in a content script in both browsers is this:
console.log(window.frames.length + ':' + parent.frames.length);
Without iframes this prints 0:0, in a top-level window containing one frame it prints 1:1, and in the only iframe of a document it prints 0:1.
This allows my extension to determine in both browsers if there are any iframes present, and additionally in Firefox if it is run inside one of the iframes.
Since you are asking in the context of a facebook app, you might want to consider detecting this at the server when the initial request is made. Facebook will pass along a bunch of querystring data including the fb_sig_user key if it is called from an iframe.
ReplyDeleteSince you probably need to check and use this data anyway in your app, use it to determine the the appropriate context to render.
Use this javascript function as an example on how to accomplish this.
ReplyDeletefunction isNoIframeOrIframeInMyHost() {
// Validation: it must be loaded as the top page, or if it is loaded in an iframe
// then it must be embedded in my own domain.
// Info: IF top.location.href is not accessible THEN it is embedded in an iframe
// and the domains are different.
var myresult = true;
try {
var tophref = top.location.href;
var tophostname = top.location.hostname.toString();
var myhref = location.href;
if (tophref === myhref) {
myresult = true;
} else if (tophostname !== "www.yourdomain.com") {
myresult = false;
}
} catch (error) {
// error is a permission error that top.location.href is not accessible
// (which means parent domain <> iframe domain)!
myresult = false;
}
return myresult;
}
There is now also an official way to do it over the Graph API: http://developers.facebook.com/blog/post/586/
ReplyDeleteIt's an ancient piece of code that I've used a few times:
ReplyDeleteif (parent.location.href == self.location.href) {
window.location.href = 'https://www.facebook.com/pagename?v=app_1357902468';
}