Develop Reference

How do I use the .done() callback to run a function for new data being loaded on request?

I have a page displaying data from a json feed and I also have a button which loads more of the feed on click of a button. My aim is to append some content inside the page for each feed item. I have been able to create a function which does this on load of the page, but I am unsure how to make this work with the aysynchronous loading of more data.
I understand I need to use the .done() callback to make this work but need some guidance how to implement it correctly.
This function appends the new content initially:
function appendFeed() {
$('.feed__item').each(function (index) {
$feedItem = $('.feed__item', $(this));
$feedItem.append('<div class="feed-gallery"></div>');
for (var i = 1; i <= 5; i++) {
var $count = i;
if ($count > 1) {
$('.feed.gallery', $(this)).append('<div><img data-lazy="//placehold.it/50x50"></div>');
};
});
}
This is where the .done() callback is referred, on click of a button:
$('button').click(function(){
$.getJSON(uri, function (json, textStatus) {
// do stuff
}).done(function (json) {
// do stuff - in my case this would be appendFeed()
});
});
I have already called the appendFeed() function, but if I put it inside the .done() callback on click the button, then it appends the feed again. How do i prevent the duplication for the feed that is already on the page?

This is how you will write.
<script type="text/javascript">
$.getJSON("/waqar/file.php").done(function (data) {
$(".output").append(data);
});
</script>

jquery loading when load

i have script like this
function manualSeat(){
$('.dimmed').show();
$("#petaKursi").load('url');
$('#wagonCode').val('');
$('#wagonNumber').val('');
$('#selSeats').val('');
selectedGerbong = '';
selectedSeats = Array();
$('#manualSeatMap').show();
$('.dimmed').hide();
}
that code above doesn't work maybe because code doesn't wait until load syntax finish loading,..(maybe)
what i want to ask is,how to make my $('.dimmed')
works like loading that start when begin(show) loading and stop when loading finish(hide)
what i want is like this::
page load(with every div)=>click a button=>load a page to div(when loading,showLoader),when finish loading (hideLoader)

try this:
var dimmed = $('.dimmed');
var showLoader = function () {
dimmed.fadeIn();
};
var hideLoader = function () {
dimmed.fadeOut();
};
document.addEventListener('DOMContentLoaded', showLoader);
window.onload = hideLoader;
You can call showLoader and hideLoader methods whenever you want to show or hide the loader element.

thanks to Rayon Dabre
what i actually want is like this
function manualSeat(){
dimmed.fadeIn();
$("#petaKursi").load('blablabla', function() {
dimmed.fadeOut();
});
$('#wagonCode').val('');
$('#wagonNumber').val('');
$('#selSeats').val('');
selectedGerbong = '';
selectedSeats = Array();
$('#manualSeatMap').fadeIn();
}

The best way to do what you want is to use AjaxStart and AjaxStop function. This way you will fire when the Ajax call (.load is one of them) it will perform some actions.
So in your case:
$(document).ajaxStart(function (){
//I begin the ajax call so I show the layer
$('.dimmed').show();
//you can also do other stuffs like changing the tab title
document.title = 'loading...';
}).ajaxStop(function (){
//The ajax loading has ended
$('.dimmed').hide();
document.title = 'page';
});
I'd go for an ID for the layer that you use while loading to identify it.
If you want to fire this event only for some ajax call and not for other add the
global: false
attribute to that specific ajax call.

Javascript onload after ajax loading

After returning to main content by ajax load, function onload didn't run.
I can understand why, but how can I make it run in that condition?
<script type="text/javascript">
onload = function() {
if (!document.getElementsByTagName || !document.createTextNode) return;
var rows = document.getElementById('chat').getElementsByTagName('tr');
for (i = 0; i < rows.length; i++) {
rows[i].onclick = function() {
$("#chat_main").load("chat", {
m: this.id,
ajax: 1 //here we are loading another page
});
}
}
}
</script>
<script>
function return_to_main() {
$("#chat_main").load("chat", {
ajax: 1 //here we trying to load back main page
});
}
</script>
P.S. return_to_main() is binded on input type="button"

You are binding to the window.onload call. It does not magically get called every time the page content is updated. It is only called once. You need to call a function every time you want the code to run. So when the Ajax call is complete, you would been to trigger it.
BUT You are using jQuery so use it.
There is no reason why you would need to bind to every row on the table. Use event delegation. Now when the content changes, you will still have the events bound.
$( function () { //document ready
var chatMain = $("#chat_main");
chatMain.on("click", "table tbody tr", function () { //listen for clicks on table row
chatMain.load("chat",
{
m: this.id,
ajax: 1 //here we are loading another page
}
);
});
});

Call your function after the request:
$("#chat_main").load("chat", {
ajax: 1 //here we trying to load back main page
}).done(onload); // <--
If .load does not produce a promise use:
$("#chat_main").load("chat", {
ajax: 1 //here we trying to load back main page
}, onload); // <--

Need to clear a function memory. jQuery running function too many times

Initially, I had a problem that a click event was firing multiple times, but I have managed to overcome that with a probably over use of unbind() and one() as you'll see in my code below!
What I have here is some code which opens up a universally usable Modal window which I use for various things, including, in some cases a password form.
I don't think you need the HTML so I won't post that.
When a button, or an action causes the window to be required, I call the function like this:
showModalAlert(type, theWidth, theHeight, title, html, confirmThis, denyThis)
The first three variables determine how the window will look, title and html determine the content and confirmThis and denyThis are functions set immediately prior to calling this function and determine what the action should be if this is a confirm window and the confirm or deny buttons are press.
In the case of a security window, the confirm button is replace by a "sign it" button which submits a simple password form and returns a User Id from database. If a User Id is successfully returned, the script programatically presses the confirm button and in turn runs it's function as per the call to the inital opening of the modal window.
My problem is that if an incorrect password is entered, or a user cancels the window and then later without refreshing the browser window, re-enters the password correctly, the confirmThis() function is performed twice (or as many times as the incorrect password/cancel action was performed).
So, clearly, what it is doing is "remembering" the confirmThis function each time.
As I said, initially, the password success function was clicking confirmIt twice, copious use of one() has fixed this, it is now definitely only clicking confirmIt once, but it is still performing the function multiple time.
How can I clear this function and ensure it is only performed once?
The function from which I am calling the modal window looks like this:
$('#saveDelivery').click(function () {
function confirmIt() {
formData = (JSON.stringify($('#delDetail').serializeObject()));
saveData(formData);
$('#saveDelivery').removeClass('centreLoader');
};
showModalAlert('security', '300px', '185px', 'Security!', 'You need to "Sign" this action.', confirmIt, '');
});
It's simply a click on the saveDelivery element, the confirmThis function is declared at this point and submits an AJAX form
the actual showModalAlert function is below:
function showModalAlert(type, theWidth, theHeight, title, html, confirmThis, denyThis) {
// stuff that opens the alert window \\
if (confirmThis == '') {
$('#confirmIt').one('click', function () { $('#closeAlert').one('click').click(); });
} else {
$('#confirmIt').one('click', function () { confirmThis(); $('#closeAlert').one('click').click(); });
};
if (denyThis == '') {
$('#denyIt').one('click', function () { $('#closeAlert').one('click').click(); $('#signIt').unbind(); });
} else {
$('#denyIt').one('click', function () { denyThis(); $('#closeAlert').one('click').click(); $('#signIt').unbind(); });
};
if (type == "confirm") {
$('.closeAlert, .signItForm').hide();
};
if (type == "alert") {
$('.alertConfirm, .signItForm').hide();
};
if (type == "fixedAlert") {
$('.closeAlert, .alertConfirm, .signItForm').hide();
};
if (type == "security") {
$('.signItForm').show();
$('.closeAlert').hide();
$('#confirmIt').hide();
$('#signIt').unbind().fadeTo('fast',1);
};
};
$('#signIt').live('click', function () {
var formData = (JSON.stringify($('.secureSign').serializeObject()));
var signitPwd = $('#signItpwd').val();
var jsonURL = "/jsonout/getdata.aspx?sql=SELECT id, password FROM users WHERE password ='" + signitPwd + "' LIMIT 1&output=json&usedb=new&labelName=any&fileName=";
$.getJSON(jsonURL, function (data) {
if (data.length > 0) {
$('.savingUserID').val(data[0].id);
$('#confirmIt').one('click').click();
$('#signIt').fadeTo('fast', 0);
$('#confirmIt').show();
} else {
$('#signIt').fadeTo('fast', 0);
$('#confirmIt').one('click').show();
$('.closeAlert').show();
$('.alertConfirm, .signItForm').hide();
$('#alertTitle').html("Error!");
$('#alertContent').css({ 'text-align': 'center' }).html("Password Denied");
};
});
});

From my understanding of $.one, it merely runs the event ONCE. If you bind it twice to the event, it will run twice instantaneously, but no more.
Example: http://jsfiddle.net/qCwMH/ (click the button, and it will run the event 4 times).
Each time you click saveDelivery, you are infact, binding another $.one event to #confirmIt.
What you could do is unbind your events from confirmIt and denyIt at the start of the modal function (i.e. $('#confirmIt, #denyIt').unbind('click');, and then you will assign them fresh each time that function is called, rather than building on top of them. Not ideal, as binding/unbinding uses more resources than other options, but just give that a try to start with perhaps?

Resend AJAX request with link?

Is there anyway to reload just the AJAX request, so that it updates the content pulled from the external site in the code below?
$(document).ready(function () {
var mySearch = $('input#id_search').quicksearch('#content table', { clearSearch: '#clearsearch', });
var container = $('#content');
function doAjax(url) {
if (url.match('^http')) {
$.getJSON("http://query.yahooapis.com/v1/public/yql?"+
"q=select%20*%20from%20html%20where%20url%3D%22"+
encodeURIComponent(url)+
"%22&format=xml'&callback=?",
function (data) {
if (data.results[0]) {
var fullResponse = $(filterData(data.results[0])),
justTable = fullResponse.find("table");
container.append(justTable);
mySearch.cache();
$('.loading').fadeOut();
} else {
var errormsg = '<p>Error: could not load the page.</p>';
container.html(errormsg);
}
});
} else {
$('#content').load(url);
}
}
function filterData(data) {
data = data.replace(/<?\/body[^>]*>/g, '');
data = data.replace(/[\r|\n]+/g, '');
data = data.replace(/<--[\S\s]*?-->/g, '');
data = data.replace(/<noscript[^>]*>[\S\s]*?<\/noscript>/g, '');
data = data.replace(/<script[^>]*>[\S\s]*?<\/script>/g, '');
data = data.replace(/<script.*\/>/, '');
data = data.replace(/<img[^>]*>/g, '');
return data;
}
doAjax('link');
});
Right now I have a button which reloads the entire page, but I just want to reload the AJAX request. Is this even possible?
Edit: I need to specify more. While it can easily call the AJAX again, can it also replace the info that is already there?

You just need to call the doAjax function again on button click...
$("#buttonID").on("click", function() {
doAjax("link");
});
Add that into the above document.ready code and set the button ID correspondingly.
Then change
container.append(justTable);
to
container.html(justTable);

In your doAjax function you append HTML onto an element. If you overwrite the element's HTML instead of appending to it then the HTML will be "refreshed" each time the doAjax function runs:
Simply change:
container.append(justTable);
To:
container.html(justTable);
And of-course you can bind a click event handler to a link (or any element) like the rest of the answers show. Make sure you bind the click event in the proper scope (inside the document.ready event handler) so the doAjax function will be accessible from the click event handler.