Detect when AJAX changes HTML in a DIV in WebBrowser - ajax

After I load a page through a WebBrowser, and I click a link that fires an AJAX script, I need to detect when the AJAX java script finishes loading HTML changes into a div. Since no DocumentCompleted event is fired when the AJAX script is run, I don't know when it finish running. Is there a way I can attach an event to be raised after I know 100% that the javascript finished changing the div?
The project is in C#.
Thanks

I did something similar recently (using jQuery):
$('#mydiv').change(function(){
// do stuff
}
);
Granted, I also use jQuery to set the HTML of that div. I suppose one non-jQuery approach for you could be to set HTML through your own function, which in turn can fire an onchange event.
#New in town: From my experience that is not correct. I use this on multiple DIVs that never get focus in the first place, and it works well and consistently. The normal behavior is as you describe, and normally only applies to the INPUT and SELECT elements, but this is not the case with jQuery.

There is no event. You must patch the JavaScript callback that the browser runs when the reply for the AJAX request comes in. This will contains code like "div.innerHTML = ...". Just put your code below that.

Related

How to detect when a website which uses AJAX is completely loaded?

For a website, which doesn't use AJAX I'm using OnDocumentComplete event to know when the page loading is complete.
My question is, how can I detect when website, which uses AJAX requests is ready (e.g. when a website which is fetching some search results by using AJAX finished its work) ?
Ok here is a trick i developed my self.
1-in your html page make a div and set its text to "false".
2-in you server side put a javascript at the end of your returning code. for example your site returns following text upon an ajax call.
a
b
c
d
e
so after this text put a javascript code that will change the text of div from "false" to "true"
so what will happen is that once you receive all the data from ajax call you will also receive the javascript code and that code will run and set the value of div.
so in your page once all data is received you will see the indicator div. and you will know that you have received all data. you can also run functions in similar way upon completion of data.

jQuery Showing an Ajax loader during transmission & Prevent Multiple Submits

I have an app that has several different types of form elements which all post data to the server with jQuery AJAX.
What I want to do is:
Show a loader during AJAX transmission
Prevent the user from submitting twice+ (clicking a lot)
This is easy to do on a one off basis for every type of form on the site (comments, file upload, etc). But I'm curious to learn if that is a more global way to handle this?
Something that's smart enough to say:
If a form is submitting to the server and waiting for a response, ignore all submits
Show a DISABLED class on the submitted / clicked item
Show a loading class on the class="spinner" which is closest to the submit item clicked
What do you think? Good idea? Done before?
Take a look at the jQuery Global Ajax Event Handlers.
In a nutshell, you can set events which occur on each and every AJAX request, hence the name Global Event Handlers. There are a few different events, I'll use ajaxStart() and ajaxComplete() in my code sample below.
The idea is that we show the loading, disable the form & button on the ajaxStart() event, then reenable the form and hide the loading element inside the ajaxComplete() event.
var $form = $("form");
$form.ajaxStart(function() {
// show loading
$("#loading", this).show();
// Add class of disabled to form element
$(this).addClass("disabled");
// Disable button
$("input[type=submit]", this).attr("disabled", true);
});
And the AJAX complete event
$form.ajaxComplete(function() {
// hide loading
$("#loading", this).hide();
// Remove disabled class
$(this).removeClass("disabled");
// Re-enable button
$("input[type=submit]", this).removeAttr("disabled");
});
You might need to attach to the ajaxError event as well in case an AJAX call fails since you might need to clean up some of the elements. Test it out and see what happens on a failed AJAX request.
P.S. If you're calling $.ajax or similar ($.getJSON), you can still set these events via $.ajaxStart and $.ajaxComplete since the AJAX isn't attached to any element. You'll need to rearrange the code a little though since you won't have access to $(this).
I believe you have to do 2 for sure and 3 to improve usability of your app. It is better to keep backend dumb but if you have a security issue you should handle that too.

AJAX and iFrame: Calling AJAX from inside the iFrame to Update an Outside DIV

I have a page where a user can upload a file along with some other input. Because I wanted this to be AJAX-like, I resorted to using an iFrame to accomplish this.
After the file is uploaded and an iFrame is loaded with a response page, I need to update a DIV outside of the iFrame with an AJAX call. The reason for separate updates, is that the result of the outside DIV depends on the input that the user provided with the file input.
Can this be done? Am I approaching this the wrong way?
Thank you!
UPD: Can the returned client code from within the iFrame "see" elements outside that iFrame?
Write your code in the onload event of the page loaded into the iframe. Then top will give you the top frame or parent will give you the parent frame.
Yes , it can be done. But you can do away with,the need for an AJAX-call , to update the outside the div.
Have your, servlet(assuming you are using JSP/servlets) that accepts the mutlipart request(the servlet that accepts the upload), return the intended response (to be shown on the refreshed iFrame), and ALONG WITH IT, the necessary information from the file input. This way you have all the necessary details on the client, in one response. A simple javascript function can achieve , updating the outer div with the information from the file input.

jQuery: Targeting elements added via *non-jQuery* AJAX before any Javascript events fire? Beyond the scope of live()?

Working on a Wicket application that adds markup to the DOM after onLoad via Wicket's built-in AJAX for an auto-complete widget. We have an IE6 glitch that means I need to reposition the markup coming in, and I am trying to avoid tampering with the Wicket javascript... blah blah blah... here's what I'm trying to do:
New markup arrives in the DOM (I
don't have access to a callback)
Somehow I know this, so I fire my
code.
I tried this, hoping the new tags would trigger onLoad events:
$("selectorForNewMarkup").live("onLoad", function(){ //using jQuery 1.4.1
//my code
});
...but have become educated that onLoad only fires on the initial page load. Is there another event fired when elements are added to the DOM? Or another way to sense changes to the DOM?
Everything I've bumped into on similar issues with new markup additions, they have access to the callback function on .load() or similar, or they have a real javascript event to work with and live() works perfectly.
Is this a pipe dream?
.live() doesn't work like this, it's a common misconception. .live() creates an event handler at the DOM root and waits for events to bubble up to it. If the selector matches the event target, .live() will fire the bound event.
It doesn't look for new objects and bind events to them in any way, rather it just listens for a bubble, and doesn't care when that object was added to the DOM.
You need to fire whatever code is needed to run manually when your load operation completes.
What will this is the livequery plug-in, look specifically at the livequery( matchedFn ) call.
You can do something like this:
$('#myID').livequery(function() { $(this).offset()...stuff });
i guess this is what you are looking for http://ananthakumaran.github.com/2010/02/19/wicket-post-ajax-handling.html

onLoad or similar for Ajax?

Good day,
I was wondering if there is a way to make Ajax move on to the next code segment only when all the elements included in the server-side code page are fully loaded. When the retrieved data is text-only there’s no problem, but sometimes there are photos included.
This is part of the code I have been using:
xajx.onreadystatechange = function(){
if(xajx.readyState==4){
document.all.div1.innerHTML = xajx.responseText;
document.all.div1.style.display = “”;
}
}
The thing is that when the response is retrieved (readyState set to 4) and div1 is displayed, the Photo has not been completely loaded yet, so actually the user can see the process of the picture slowly appearing, as he would in any other “normal” case. What I want to do is making div1 available for display only once all the components are fully loaded while meanwhile the system does its stuff in the background. Before Ajax I used hidden iframes like everybody, so I could enclose an onload event handler within the iframe tag (or in an external script), so div1 would appear only after the iframe has fully loaded, photos included.
Any idea?
You can use the 'onload' event on images themselves. You'll need to work out how to attach that event when you are downloading the code dynamically as in your case.

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