The problem is this:
When I change the content on a page via AJAX and then use the browsers back and forward button to go to the same page, then I will be presented with the content of the page before the AJAX was executed.
This seems to be specific to IE (confirmed on version 8), as Firefox will render the last version of the page.
Just to clarify, I don't need (nor want for usability reasons) to replay the AJAX calls when clicking back/forward.
We were thinking about firing the last AJAX call on page load (if that event is even triggered), but we would like not to force everyone to wait through the additional AJAX call when going to the page the second time, also this would cause the first real load of the page to be slower as well.
Maybe someone has a good solution for this?
I think it will be useful : http://www.ibm.com/developerworks/library/os-php-rad2/ ;)
Related
If you go to http://jsbin.com/ibozun/2, hit "Add Item," and then hit "Save," you will see that a second dialog is opened on top of the first one. The form in the dialog is posting to itself (no action defined) - this is by design. Because the dialog has duplicated itself, now you have to hit "Cancel" 2 times to get it to close.
The use-case for this setup is a MS MVC3 page with unobtrusive JQuery validation on it. The default scripts (in other words, I have no custom validators - the scripts are straight from MS) cause an ajax call to the server, and JQM treats that the same as a self-posting form - so you wind up with a duplicate dialog if validation fails.
A similar thing happens if the second page as a page, rather than a dialog - the form posting to itself results in a second history entry in the browser, so to get back to page 1, you have to hit back 2 times.
I believed this be a bug in JQM, but after submitting a bug on GitHub, I was told that this is the expected behavior. So, assuming this behavior that will not be changing in the framework, how do I prevent this from happening for my instance (preferring NOT to edit the framework JS)? Do I have to write my own ajax calls for validation so that I can prevent JQM from knowing that anything has happened? That seems unfortunate...
One idea I had was to detect that the nextPage and current page are the same on "pageHide", and manipulate the dialog/history myself, but have had no luck.
Thanks in advance!
First, there is no dialog duplication in the example. Second, my response and an explanation as to why solving the history issues with posting back to the same page for users of the library is hard can be found here. This example is particularly thorny because it's also in a dialog which we don't support linking to, so disabling ajax for the form (ie forcing it to reload), which would work if it were embedded in a page, won't serve.
The quick solution here is to switch the dialog to a page and add the data-ajax=false data attribute to the form. Mind you this causes a page flash/reload and requires that the form document be fully formed with a head including javascript,css, etc.
I have a form that uses Html.BeginForm and for most cases this works as you would expect.
But in some situations I display a partialview that does several ajax calls to populate itself. When the partial view has been displayed I need to click the submit button twice to get the form to post. On the first click I can see the form refresh, and then on the second click the form actually posts. This is when using IE9, using Firefox the posts work on the first click.
I would like to know if anyone has seen this behaivor before I spend a lot of time trying figure this out.
Install Fiddler, open it up, and then reproduce the issue in IE. Fiddler will capture all of the requests, so you can see exactly what was sent to the server (and back).
Had a similar issue. The reason was, we had a in view and in addition we were doing $('#form').submit() as well. But the button didn't have "type" attribute. After setting button type=button. It was good.
I'm having trouble using AJAX page updates along with other AJAX scripts.
During a normal page load, the AJAX scripts (picture scrolling and picture thumbnails) work fine. But when I update a page with AJAX, these scripts (usually loaded in the header of the initial page load) stop working.
I am wondering if this is specific to these scripts and I need to look into them deeper to resolve/re-write or if I am missing something more generic in combining AJAX page updates with AJAX scripts the returned code relies on.
Embedded javascript runs fine.
Thanks for your ideas!
PS: The scripts I am using are from www.dynamicdrive.com are:
1) stepcarousel (http://www.dynamicdrive.com/dynamicindex4/stepcarousel.htm) and
23) thumbnailviewer (http://www.dynamicdrive.com/dynamicindex4/thumbnail.htm) from the
Try doing this on Firefox, using the Firebug debugger, so you can single-step through and determine what is going on with the javascript. If you are using IE8 then you can hit F12 and bring up the debugger for that environment also.
Once you have some idea what is going on then you can explain what you are seeing, what browsers you have tried and you will get more help.
I am a beginner using ajax and I always thought that it is completely asynchronous. But I discovered that a call can be interrupted by a page reload or a page change (like clicking on a hyperlink). I was under the impression that when an ajax call is started, it is carried out no matter what the browser does afterwards. Is that wrong?
Now to the specific problem I am having: think of an online test where users answer questions (by typing into textboxes). When a textbox loses focus, an ajax call is triggered which persists the value of the textbox to a DB. That works well when changing between textboxes. However, I also have a submit button which triggeres a post action to another page (it is the submit button). When I enter something into a textbox and click on the button afterwards, the call is not carried out. Moreover, when I type into a textbox, click somewhere else (also triggering the call) and swiftly click on the submit button, the call is also not made. Is that expected behaviour?
The reason I am using ajax in the first place is to persist the values so when something unforseeable happens, like a browser crash, the already typed in text is already saved.
Is my way of thinking wrong? How would you go about solving this problem?
Thank you for your time!
AJAX is asynchronous.
When you send an AJAX request the javascript engine sends it off and sets up a handler for the response.
However, if you send an AJAX request to the server and then navigate away from the page before it is received, nothing will happen. Why? Because with each page load the entire Javascript environment is tore down and reinitialized, it has no idea what happened on the last page.
For your problem I would intercept the form submit action and do whatever you need to do with the data, and then submit the form.
Edit: In response to your comment. You are correct. If the ajax request is sent, and you're not depending on it's return value, then it should not matter.
I'd suggest debugging your problem with Firebug to see if the AJAX call is really being sent properly, and to confirm your server is properly processing it.
Unless you do something special with persistent local storage, all javascript and ajax calls are blown away when a new page is loaded over the current page. Also when a submit is done on a form.
To save things intra-page, save the data asap. Eg, perhaps save on key-up, perhaps periodically with a timer, not just on lose-focus.
Re submitting the page: change the on-click behavior to first store, then to go to a new page.
All of the effects that you are seeing are normal.
Also, be sure to test on both slow (ie 6 or 7) and fast browsers (chrome)
I am implementing a web application using ASP .Net and C#. One of the pages has a requirement that it always needs to be fetched from the server, rather than from the local browser cache. I have been able to achieve this.
We have a back button in the application, which simply invokes javascript:history.back() method. The problem is that when the back button is clicked to navigate to the page which is always to be reloaded from the server, the browser displays a "Web page expired message".
The intent here is to force the browser to reload the page rather than display the web page expired message.
Any help would be highly appreciated. Thanks a ton in advance.
You will probably need to change the implementation to make the browser load the URL explicitly:
window.location.href = 'http://....';
instead of invoking the back button, since the intention of the back button is to get the last page from the cache.
(If browsers would not act that way, they would re-send your form data multiple times when using the back button during a registration process or similar.)
You mean you want to control browser behaviour, which is not possible. I doubt you can solve it that way. You could set the expiration time to a small value (1 minute perhaps?) so that the page is still valid if one navigates back quickly.