I have a textarea where people can write comments and click a button to post them. The processing is done with AJAX and so I want that as long as the server is processing the user request (and after too), the button and textarea will be blocked for editing/writing/clicking.
It's very similar to how comments on Youtube videos work.
Do you have an idea how to do this? I'm very new to ajax and so I would appreciate a detailed response,
thanks!
Its simple Gal, On button click
document.form.myTextArea.readOnly=true;
If you did no one can edit and also you change the color of the textbox
document.getElementById('myTextArea').style.background = "#FF0000";
Gal,
You can use update progress to disable buttons or textareas.
http://www.asp.net/Ajax/Documentation/Live/overview/UpdateProgressOverview.aspx
It's the easiest!
before you make ajax call, in the javascript function from which you will make ajax call, you can grab the textarea or button by document.getElementById('idOfTextAreaOrButton') method and set the disabled property to true.
Related
I have a nice drop down area, but if I set that to class"dropzone" then the form elements are not sent.
If I add class"dropzone" to the form, then the form elements are sent, but the thumbnails appear under the form, the submit button, etc.
How please do I tell dropzone to use my template at id "#dropzone_thumbs_here" or class ".dropzone_thumbs_here". Do I have to fully write my own thumbnail handler? Or send form details separately? Or is there a better method !!
Sorry, I missed the answer because in the documentation it was under tips and not configuration.
In the config parameters, just added:
previewsContainer: "#myPreviewContainerID",
I am taking my first steps with Ajax while working on a Grails application. I am using
<g:form ...>
<g:submitToRemote ... />
</g:form>
in the most simple way and it worked great out of the box (Thanks grails!). The problem is, that the Ajax call needs about 2 seconds to return and update the html (at least on the test system) and during that time, the user can (and actually does quite often) hit the submit button again. At the moment this results in a 2nd call being made that finally ruins the output (an error msg says, that one cannot submit the same data twice).
What is the best way to prevent this?
Thanks in advance for your input!
The best way to handle this is to disable the submit button in your onSubmit() function. Honestly, I don't know why more sites don't do this. I often go the next step and instead of disabling the submit button, I put the submit button in a span tag and replace the contents of the span tag with static text "Please wait..." That way your users get visual feedback they pressed the button and "top men are working on it".
As dj_segfault said you can do that.
If you want to validate this in your controller, take a look in "Handling Duplicate Form Submissions" in the official docs:
http://grails.org/doc/latest/guide/theWebLayer.html#formtokens
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.
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.
for example:
user submit a comment , I add the comment in the page by javascript , then do the ajax. if ajax post failed ,tell user that something wrong happend.
in this way , it can improve user experience . and the probability of ajax failed is not low. but I didn't seen which site is using this technology , so is this method possible?
Actually, I'd say that stackoverflow uses this technique :
Make sure you are using firebug, and have the console displayed on the bottom of your browser scree
Click on (for instance) the arrow to upvote
you will see the arrow immediatly becomes orange, to indicate you have upvoted)
but looking at firebug's console, you will see the Ajax request starts only after the arrow has changed color -- or, at least, it is not finised yet when the arrow has changed color.
Considering the probably of the Ajax request failing is pretty low, changing the arrow immediatly indicates the user his vote has been taken into account... Even if it's not true before a couple milliseconds ;-)
You can add the comment via Javascript but you've also pointed out exactly why you shouldn't: what if it fails? Do you then remove the content?
In my opinion, adding it to the page implies to the user that it has worked. I would leave the comment in a form field until the AJAX submit succeeds. If that fails you can tell the user and they can try to submit again or whatever.
Of course, there is no functional reason why you couldn't do this.
Yes there is nothing stopping you doing this.
You add the comment in an element you create in javascript post the data and get the response code back form the ajax post.