Something overwrites window.onbeforeunload in Javascript - javascript

Hello guys,
I have a strange problem with my ASP.NET 4.5 page. For some strange reason, my window.onbeforeunload function gets overwritten every time I load the page. Inside the debugger, I can clearly see that the right value is set in my head section, if I place a breakpoint there. However, after finishing the loading process of the site, the value changes to the following:
function (a){return typeof p!="undefined"&&(!a||p.event.triggered!==a.type)?p.event.dispatch.apply(h.elem,arguments):b}
I have no idea where this is coming from. This is my code from the head section of the page:
window.onbeforeunload = function (e) { return 'Do you really want to cancel?'; };
I'm using JQuery 2.1.3 as well as DevExpress 14.2 in my project. Any idea what could be responsible for this weird behavior?
Thanks in advance!

I actually found the answer where this is coming from thanks to #DavidTansey's hint. It's the Browser Link feature that was introduced in Visual Studio 2013. It looks like Browser Link uses some old jQuery library and overwrites various handlers.
So if you are having the same issue, please try to disable the feature (the menu is next to the browser selection in the tool bar). This should solve the problem.
I'm pretty sure that this problem wouldn't appear on a real server, because it would likely not use Browser Link.

Related

How can I tell what triggered endRequest function?

Working on an asp.net website. All the controls are in an UpdatePanel.
I have some js code on my page. For some reason after docment.ready is called add_endRequest is being called (repeatedly). I've been trying to troubleshoot why this is being called, but I can't figure it out. What is the best way to tell what triggered endRequest? Any suggestions as to troubleshooting? Here's some of the code...
<script type="text/javascript">
$(document).ready(function () {
// code....
});
var prm = Sys.WebForms.PageRequestManager.getInstance();
prm.add_endRequest(function () {
alert('add_endRequest')
// code
alert('add_endRequest done');
});
An easy way (since its just the javascript side) is to use the Sources panel.
Ive used this on Chrome mostly, but I know comparable exists in other major browsers too.
https://developer.chrome.com/devtools/docs/javascript-debugging
The Sources panel lets you debug your JavaScript code. It provides a graphical interface to the V8 debugger.
Find the line you want to put a breakpoint on, click the line number then see the stacktrace and other info in the right.
You can use that to start looking at what is triggering and place other breakpoints if required to see the local variables that helped cause this.
You can also use this to make local changes to a file, though ofcourse when you refresh these are lost, but it can be useful for quick debuging too.
As a sidenote, if you are wanting broad advice like this probably best you take a look at https://softwareengineering.stackexchange.com/, some awesome resources there too.

Whitescreen issue in IE9 - Removing iframe

I"m wondering if anyone can give me some insight into a really strange IE9 issue I've been struggling with.
I'm finishing up production of a site for work - it works well in ff/chrome/ie7/ie8 with no script errors.
On IE9 the last step of the application causes the entire tab to whitescreen with no script errors or warnings. (changing the document mode to ie8 will fix the problem but is obviously unsuitable for production)
Unfortunately the site pretty complex with a ton of ajax, and in-page scripts so I can't really post the relevant code easily. I'm more trying to figure out how to diagnose this.
I've checked the IE error logs and they are empty. Web developer tools tells me nothing. The site is not using any plugins (Flash/Silverlight, Ect. ) just javascript w/jQuery.
There is a PDF being displayed in an iframe around the step where it fails - but a nearly identical pdf is displayed in the previous step (using the same method) without problem. The code fails around a call to the jquery UI window but I can't seem to get the exact line.
If anyone has a clue how to try to diagnose this further I'd really appreciate it. I can keep hunting for the bug but I've never seen this kind of behavior before and just am not sure what I am looking for.
Thanks for all the input on this. Sorry I got completely overwhelmed by a few projects at once so I wasn't able to post updates on the debugging steps.
It took forever but I finally realized that everything was crashing when I closed the dialog containing the first PDF.
One of my helper functions was opening the dialog and automatically destroying the contents on close. Normally this works fine as I'm either removing a div containing the page fragment, or the iframe.
In this situation I had a page fragment loaded into the dialog which contained some buttons and the pdf iframe. I called the .remove() method on the parent element containing the iframe rather than the iframe itself. For some reason this seems to work fine in every other browser - but in IE9 it pretty much kills the page rendering without any warning or message.
I strongly suspect that the culprit is the adobe plugin but I'm not entirely sure.
Here is the fix-
Html:
<div id="container">
<iframe src="loremipsum.pdf"></iframe>
</div>
Javascript:
//Ruins my entire week
$("#container").remove();
//Works as the pdf is removed directly
$("#container").find("iframe").remove().end().remove();
I ran into the same issue on IE11 while trying to remove an iframe in a div with AngularJS. Removing the iframe first would just cause the same issue, so I navigated the iframe src to a new page (about:blank) first, then removed the div which worked. Hopefully this helps someone with a similar problem.
Pseudo-code below:
$ctrl.iframeUrl = 'about:blank'; // change the iframe url here
$timeout(function(){
$ctrl.removeIframe(); // remove the iframe here
});
As a thing to try - see what's in the IE9 DOM viewer after it whitescreens. There's a decent chance that most of the stuff is there and just not rendering properly (or having something else rendered over it). At the very least, knowing whether it's losing a ton of stuff out of the DOM or not should give you some useful data.

IE 8 Frameset / Javascript error

Ok here's the problem. I have a page that works in FF3 and Safari4 no problem. It's IE8 that's causing the issue, go figure. I remember in the Netscape days when it was the opposite.
Anyways,
So i'm building a website for a friend - i have three pages. the first two work fine on their own, but when they are combined in a frameset in the third (main.html) in IE8 all hell breaks loose. here are the pages:
www.wither.org/Karoline/navigation.html
www.wither.org/Karoline/portfolio.html
http://www.wither.org/Karoline/main.html
& my CSS if you want it: www.wither.org/Karoline/css/styles.css
if anyone can figure out how to fix this, i'd be eternally grateful. It's completely baffling to me and i've tried all kinds of options. i upgraded jquery to the latest version but then my scroller didn't work and i can't dive too much into the javascript code right now.
Please if you could help out, it would mean a lot to me. this has to go live sometime tomorrow.
There is a JS error when executing the following line of code document.getElementById("loading").style.display = 'none';
in the portfolio page.
Apparently, the element with id 'loading' is not being found. However, if I continue execution of the JavaScript on the page (from within the debugger), there are no issues, and the behavior is the same as in Firefox. This is indicative of a concurrency issue - the element 'loading' is not present in the DOM yet, but the script is attempting to change the element's style.
In order to fix this issue, you will have to ensure that the 'loading' element is present in the DOM before its style is being changed. In fact, you could delay the execution of the onload event handler (using window.setTimeout), until a point where the element is present in the DOM.
What's the actual javascript error?
And IE does have an issue in regards to invalid/broken markup inside of frames, I would try
a) commenting out each script and see which causes the js error
b) if commenting out all the js did nothing it might be related to the invalid markup inside of a frame issue, in which case I'd ditch frames alltogether.
yeah....
so thanks so much for your help. problem solved and i figured the other CSS error. should have picked up on that one earlier.
so site is working and if you want to see what happened with your help,
http://www.wither.org/Karoline
it works perfectly cross platform. made the deadline with hours to spare. thanks SO much. can't believe how well this worked.

TinyMCE not working with Chrome when I dynamically setContent

I have a site that I put:
<body onload="ajaxLoad()" >
I have a Javascript function that then inserts data from my database into the text editor by using the setContent Javascript method of the textarea. It seems fine in Firefox and IE but in Chrome sometimes nothing shows up. There is no error, just a blank editor.
In the body section I have:
<textarea id="elm1" name="elm1" rows="40" cols="60" style="width: 100%">
</textarea>
In the head section I have:
function ajaxLoad() {
var ed = tinyMCE.get('elm1');
ed.setProgressState(1); // Show progress
window.setTimeout(function() {
ed.setProgressState(0); // Hide progress
ed.setContent('<p style="text-align: center;"><strong><br /><span style="font-size: small;">General Manager's Corner</span></strong></p><p style="text-align: center;">August 2009</p><p>It’s been 15<sup>th</sup> and so have a Steak Night (Saturday, 15<sup>th</sup>) and a shore Dinner planned (Saturday, 22<sup>nd</sup>) this month. urday, September 5<sup>th</sup>. e a can’t missed evening, shas extended it one additional week. The last clinic will be the week of August 11<sup>th</sup>. </p><p> Alt (Tuesday through Thursday) </p><p> I wouClub.</p><p> </p><p> </p><p> </p><p> <strong></strong></p>');
}, 1);
}
I am not sure if its some of the formatting that Chrome is rejecting but it seems like if TinyMCE can parse it in one browser, it should be able to do it in any browser, so I am confused.
Any suggestions?
Background:
For various reasons onload() is not considered the proper approach for loading Javascript, see for example Launching Code on Document Ready, with the most important/noticeable one being that Javascript code isn't run until the page has finished downloading entirely, including images and the like, which might take an eternity therefore (e.g. if an external banner ad server is down etc.).
Instead it is recommended to load Javascript as soon as the DOM is ready, but unfortunately there is no cross browser compatible native solution for this, see Getting notified when the page DOM has loaded (but before window.onload); please note that my entire answer is based upon the most excellent Javascript library jQuery, which offers a cross browser solution for this problem, consequently I'd definitely favor the two higher voted answers over the accepted solution myself.
Likely cause:
Your issue seems to be caused by the opposite behavior though: Chrome facilitates the WebKit rendering engine, just like Safari, and for the latter onload() is discussed to behave differently, see section When does onload fire? in Is Safari faster?. Another description of this problem specific to Chrome can be found in window.onload not working correctly in Chrome, without an explanation though.
In conclusion I suspect onload() to fire before the DOM is actually loaded completely, at least concerning the requirements of TinyMCE, which is notoriously fragile regarding issues like this and simply ceases to load.
Possible solution:
Just facilitating attribute defer on the script tag as outlined in window.onload not working correctly in Chrome is again not cross browser compatible, hence I'd simply go with the widely deployed and proven approach of using the already mentioned jQuery cross browser solution for the onload() problem, which is good practice anyway and should in principle take care of your inverse issue as well.
Update:
There are indeed some bugs filed against WebKit which could back my conclusion (no matter whether this behavior actually constitutes a bug or is intentional), see:
onload sometimes fired before all resources are loaded
window.onload fires before all subresources loaded
Window.onload is firing before image resources are loaded
I had a similar problem (editor not showing in chrome) and read in some forum, that if tinyMCE is unable to locate some files, it just stops loading. Try tracking down if everything is found using firebug's net tab (clear your cache first).
First of all; see to it that you have the latest version of TinyMCE.
I could not reproduce your problem given the information you provides. It seems just fine ( with the faked ajaxload ).
You could always try to go the "back entrance" in;
var myed = document.getElementById('elm1_ifr');
myed.contentDocument.getElementById('tinymce').innerHTML="<p style=\"text-align: center;\"><strong>hacking <span style=\"font-size: small;\">my</span> way in.</strong></p>";
Hope you good luck!
SOLUTION:
Ive been struggling with the TinyMCE toolbar not appearing in all kinds of secnarios....it would work in one user's IE browser, but not another. It would not work in Firefox or Chrome, etc.
Turns out if in the newest 3.3 version there are STILL bugs they have not fixed. This one occurs when in your webpage JavaScript code, where you instantiate the TinyMCE, if you added code for the plugin part where you load up two specific plugins, the toolbar fails to appear and you see HTML:
plugins:
"safari,spellchecker,pagebreak,style,layer,table,save,advhr,advimage,advlink,emotions,iespell,
inlinepopups,insertdatetime,preview,media,searchreplace,print,contextmenu,paste,directionality,
fullscreen,noneditable,visualchars,nonbreaking,xhtmlxtras,template,**imagemanager,filemanager**",
Remove all references to imagemanager and filemanager in your web page, then refresh your browser...
When you do, retest in Chrome and Firefox and IE and the TinyMCE suddenly appears! Wow....a miracle, huh?
Turns out their "main developer" hasn't fixed the issue but does explain it as such, if you want to try and still use those plugins and yet fix the problem. His quote is as follows:
"If the ImageManager/FileManager are old they might not use the new
scriptloader api. And the new 3.3 version will load all dependent
scripts async instead of sync. - Spocke - Main developer of TinyMCE"
There are a few ways to set content in a TinyMCE editor. If you want the content to be there when the page first loads, you can just put it between the tags.
Otherwise, you can do this through script in the following way:
window.onload = function() {
tinyMCE.getInstanceById("ProfileText").setContent('test');
};
I have wrapped the code in a window.onload block. If you have other functions that set content dynamically through this way after the TinyMCE editor has already loaded, then you do not need that.
There is an option oninit for the function tinyMCE.init(), put your method there:
tinyMCE.init({
oninit: function(){
tinyMCE.activeEditor.setContent('blah');
}
});
It works this way.
The editor is not fully loaded on document load event, as it the editor loader will post-load a bunch of files.
same problem here, ie needs
var ed = tinyMCE.get('content');
ed.setContent('zzz');
other browsers
document.getElementById("content").innerHTML="zzz";
i am quite disapointed
will need to check browser in javascript to get it working properly, thats suxx

Safari issues with javascript + css

I have some strange behavior going on with safari, im using the jQuery.GridLayout plugin and css for styling.
Just for some context, this website layout is a simple header followed by the content which are a collection of blocks (each block is a div) positioned by the javascript and rearranged every time the window is re-sized.
When I direct safari to the website url all the blocks overlap to some degree (like 50%) but as I re-size the window if they have to move, automatically all goes to the correct place and only breaks if I refresh the page.
So it seems that loading the page is messing it up either because something fails to register or because something does not happen until I re-size the window.
As anyone experienced such behavior within safari?
It works perfectly in firefox and opera, its an valid html 4.01 transitional page and the css is also validated (wc3 wise that is).
I know that publishing the code is invaluable to sort this kind of issues but this is a production project and I'm obliged not to it.
Either way I appreciate any advice on were to start looking?
How do one goes about debugging this issues in safari?
Thank you.
Safari fires DomReady before linked resources are loaded. This race condition regarding calculating sizes of elements defined in CSS can usually be avoided by loading your CSS resources before any JavaScript (eg: make sure the tags appear in the before ANY tags (which are blocking, but give a change for CSS to load asynchronously). Worse case scenario, move your blocks to the last element in , leaving your tags above.
CSS concatenation of multiple files (if you have them) is also recommended.
If you aren't able to post the actual code of the page for us, you might find your solution while trying to reproduce the problem without your specific content. In the past, I've solved some of my own problems while trying to generate a page that shows the problem to post on IRC / SO. If you are able to reproduce the problem without your content, post it for the community, and an answer will be much easier to find.
My shot-in-the-dark guesses lead towards:
You may find that one of your content blocks is causing the issue.
You may find that a different library you are using is causing the issue.
Some javascript code for your layout may be running before everything is ready / filled in. From my memory, Safari is quick to display pages before images are loaded for instance.
Perhaps you need to specify the an exact width/height of some of your Grid Containers.
Small update:
(new update at bottom)
http://www.howtocreate.co.uk/safaribenchmarks.html
And also something that is working is this small script:
<script language="JavaScript">
// CREDITS:
// Automatic Page Refresher by Peter Gehrig and Urs Dudli www.24fun.com
// Permission given to use the script provided that this notice remains as is.
// Additional scripts can be found at http:
//www.hypergurl.com
// Configure refresh interval (in seconds)
var refreshinterval=20
// Shall the coundown be displayed inside your status bar? Say "yes" or "no" below:
var displaycountdown="yes"
// Do not edit the code below
var starttime
var nowtime
var reloadseconds=0
var secondssinceloaded=0
function starttime() { starttime=new Date() starttime=starttime.getTime() countdown()
} function countdown() { nowtime= new Date() nowtime=nowtime.getTime() secondssinceloaded=(nowtime-starttime)/1000
reloadseconds=Math.round(refreshinterval-secondssinceloaded) if (refreshinterval>=secondssinceloaded)
{ var timer=setTimeout("countdown()",1000) if (displaycountdown=="yes")
{ window.status="Page refreshing in "+reloadseconds+ " seconds"
} } else { clearTimeout(timer) window.location.reload(true) } } window.onload=starttime
</script>
I find it odd that a refreshing script solves the issue in safari, but if i manually refresh the page the page havoc ensues...
########UPDATE##########
Well I finally got some more time to work on this and after doing some reading a rather obvious thing came to my mind, let the content load and then format it, so for now all of my js sits between </body> and </html>.
Its not perfect since now you can catch a glimpse of the content without being properly placed when the page first loads.
Maybe ill try calling the js a second time after a few ms have passed of loading.
I know this was proposed a bit upper the thread I just needed time to get my hands dirty thanks all, Ill keep updating till I get it solved in a more proper fashion :)

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