jQuery AJAX timing issue - php

In my backend I'm using jquery 1.4.1 and the newest UI 1.8rc1. I defined a couple of buttons that do things... one is create a certain type of page using serialize functions calling a php file and then reloading the entire page. locally this always works like a charm! but as soon as i put it on my providers webserver, it only works in about 5% of times. Heres the code:
buttons: {
'Seite erstellen': function() {
$.post("webadmin/pages.create.serialize.php",$("#page-form").serialize());
$(this).dialog('close');
location.reload(true);
},
'Abbrechen': function() {
$(this).dialog('close');
}
},
Where it gets interesting is, when I put in an alert just before the location.reload part - it will always work. So there seems to be a timing issue that the serializing is executed but can't finish before the page reloads. i know the meaning of using the serialzing is not to have to reload the page, but i build a navigation etc. so i need to reload. (thinking about that now... i could really serialize everything... anyway) Is there a simple solution to this? is there something like a little timer i could build in to make it wait until the serialization is done? is this a normal behaviour?

You need to take advantage of the callback in the $.post() method:
$.post(
"webadmin/pages.create.serialize.php",
$("#page-form").serialize(),
function(data, textStatus, xhr) {
alert("I'm done loading now!");
}
);
Not exactly sure what "this" refers to inside of the callback function so I'll leave the implementation as an exercise to the reader. :-)

Related

jQuery Mobile form submission over multiple pages with CakePHP

I hope I am missing something simple here. I have a CakePHP web site I am using jQuery mobile with. I think CakePHP might have something to do with it, but I am not sure.
Anyway, I have a form I've created on my view page for adding comments. The Ajax call is working as expected on the first page that loads, but navigating to any other page prevents the data from being submitted. The console still logs 'data' each time I press the button (after using 'pagebeforeshow' as recommended somewhere else), however it seems to be the data from the original loaded page (I know this because I am currently debugging $this->request->data on the Form action page).
Clearly, I must need to "reset" the form somehow when moving across pages, but I am not sure if this is possible without refreshing the page. I do know about "data-ajax"="false" and "rel"="external" which can be used as a last resort, but I want to avoid refreshing the page if I can.
Any suggestions? Thank you.
Here is the JS I am using for the Ajax call
//<![CDATA[
$(document).on('pagebeforeshow', function(){
$(document).off('click', '#comment_add').on('click', '#comment_add',function(e) {
$.ajax({
async:true,
data:$("#sCommentViewForm").serialize(),
dataType:"html",
success:function (data, textStatus) {
//$('#comments').remove();
//$('<div id="comments"></div>').appendTo('#comments_container');
$("#comments").html(data).trigger('create');
//$('#comments_box').remove();
//$('<div id="comments_box"></div>').appendTo('#comments_container');
console.log(data);
},
type:"POST",
url:"commentsUsers/comment_add/<? echo $template['Template']['id']; ?>"});
return false;
});
});
//]]>
</script>
It was my basic lack of understanding. After lots of searching this simple post was most helpful:
Jquery Mobile Javascript not working on ajax load
Basically, I was using IDs for everything - when I switched to class names it was smooth sailing.

jQuery scrollbar plugin not working on Ajax loaded content

The problem is this:
I have a simple, two fields form which I submit with Ajax.
Upon completion I reload two div's to reflect the changes.
Everything is working perfect except a jQuery plugin. It's a simple plugin that can be called with simple
function(){
$('.myDiv').scrollbars();
}
It's simple and easy to use, but it doesn't work on Ajax loaded content. Here is the code I use to post form and reload div's:
$(function() {
$('#fotocoment').on('submit', function(e) {
$.post('submitfotocoment.php', $(this).serialize(), function (data) {
$(".coment").load("fotocomajax.php");
}).error(function() {
});
e.preventDefault();
});
});
I've tried creating a function and calling it in Ajax succes:, but no luck. Can anyone show me how to make it work ? How can that simple plugin can be reloaded or reinitialized or, maybe, refreshed. I've studied a lot of jQuery's functions, including ajaxStop, ajaxComplete ... nothing seems to be working or I'm doing something wrong here.
If you're loading elements dynamically after DOM Document is already loaded (like through AJAX in your case) simple binding .scrollbars() to element won't work, even in $(document).ready() - you need to use "live" event(s) - that way jQuery will "catch" dynamically added content:
$(selector).live(events, data, handler); // jQuery 1.3+
$(document).delegate(selector, events, data, handler); // jQuery 1.4.3+
$(document).on(events, selector, data, handler); // jQuery 1.7+
Source: jQuery Site
Even if I am totally against using such plugins, which tries to replicate your browser's components, I'll try to give some hints.
I suppose you are using this scrollbars plugin. In this case you may want to reinitialize the scrollbars element, and there are many ways to do this. You could create the element again like in the following example
<div class="holder">
<div class="scrollme">
<img src="http://placekitten.com/g/400/300" />
</div>
</div>
.....
$('.scrollme').scrollbars();
...
fakedata = "<div class='scrollme'>Fake response from your server<br /><img src='http://placekitten.com/g/500/300' /></div>";
$.post('/echo/html/', function(response){
$('.holder').html(fakedata);
$('.scrollme').scrollbars();
});
If you want to update the contents of an already initialized widget instead, then things gets more complicated. Once your plugin initialize, it moves the content in some custom wrappers in order to do its 'magic', so make sure you update the correct element, then trigger the resize event on window, pray and hopefully your widget gets re-evaluated.
If it doesn't help, then try to come up with some more details about your HTML structure.
I want to thank everyone of you who took their time to answer me with this problem I have. However, the answer came to me after 4 days of struggle and "inventions" :), and it's not a JS or Jquery solution, but a simple logic in the file.
Originally, I call my functions and plugins at the beginning of the document in "head" tag, like any other programmer out here (there are exceptions also ).
Then my visitors open my blog read it and they want to post comments. But there are a lot of comments, and I don't want to scroll the entire page, or use the default scroll bars, simply because they're ugly and we don't have cross browser support to style that, just yet.
So I .post() the form with the comment, and simply reload the containing all of them. Naturally .scrollbars() plugin doesn't work. Here come the solution.
If I put this :
<script>$('.showcoment').scrollbars();</script>
in the beginning of my loaded document (with load() ), will not work, because is not HTML and it's getting removed automatically. BUT !!! If i do this:
<div><script>$('.showcoment').scrollbars();</script></div>
at the same beginning of loaded document, MAGIC .... it works. The logic that got me there I found it in the basics of javascript. If your script is inside an HTML element, it will be parsed without any problem.
Thank you all again, and I hope my experience will help others.
If I understand you correctly, try this:
var scrollelement = $('.myDiv').scrollbars();
var api = scrollelement.data('jsp');
$(function () {
$('#fotocoment').on('submit', function (e) {
$.post('submitfotocoment.php', $(this).serialize(), function (data) {
$(".coment").load("fotocomajax.php");
api.reinitialise();
}).error(function () {
});
e.preventDefault();
});
});
reinitialise - standart api function, updates scrolbars.

AJAX/PHP – callback after finished loading data

(Not sure if I missed an already similar answered question…)
On click of a button, I'm loading various images from a database via PHP/MySQL and appending it to the body (the actual images are of course not stored in the database, the correct selection of the images is based on a posted variable).
My goal is to display a loading indicator after pressing the button and hiding the indicator after all the image data has completely loaded and displayed. This may be an easy to solve callback issue but I'm just getting started with AJAX. :)
The following is the code I currently managed to come up with. I'm guessing the load() function is not really the right one here?
Thanks for your help!
$("#somebutton").click(function(){
alert("fetching…");
$.post('loadmore.php', {
somevariable: somevariable
},
function(data){
$("body").append(data);
$(window).load(function(){
alert("finished loading…");
});
});
});
The function you have with the finished loading... alert is a success callback, so it gets executed once the AJAX call has finished. This means you don't need to use $(window).load.
Also, you can use the html method on an element to change its contents and display a message.
Something like this would work fine:
$("#somebutton").click(function(){
$('#divID').html('Loading...');
$.post('loadmore.php', {
somevariable: somevariable
},
function(data){
$("body").append(data);
$('#divID').html('');
});
});
Read the docs http://api.jquery.com/jQuery.ajax/
Use the success callback to append the body and then the complete and error callbacks to clear things up correctly.
$("#somebutton").click(function(){
alert("fetching…");
$.post('loadmore.php', {
somevariable: somevariable
})
.success(function(data){$("body").append(data)})
.error(function(){alert("oh dear")})
.complete(function(){alert("finished loading…")});
});
Remember to always have a fallback for removing the loader - nothing worse than just having a loader and no way to remove it from the page and continue using the application / web site.
I managed to solve my problem by reading and tweaking the code in the following article.
The function load() with the equation containing the self-explanatory variables [imagesLoaded >= imageCount] did the trick.
Know when images are done loading in AJAX response

Delay AJAX from loading?

I am programming an online PHP-based fantasy pet simulation game. I am not very familiar with AJAX, so please keep this in mind when answering.
On pet pages, I would like users to be able to feed/water/play with their pets without needing to reload the entire page - that's why I'm using AJAX. Here's what I have so far:
Working Script
$(function() {
$(".petcareFood").click(function(event) {
event.preventDefault();
$("#petcareFood").load($(this).attr("href"));
});
});
$(function() {
$(".petcareWater").click(function(event) {
event.preventDefault();
$("#petcareWater").load($(this).attr("href"));
});
});
$(function() {
$(".petcarePlay").click(function(event) {
event.preventDefault();
$("#petcarePlay").load($(this).attr("href"));
});
});
</script>
Working HTML
<a class=\"petcareFood\" href=\"petcare.php?pet=#&action=#\">Feed Your Pet</a>
<a class=\"petcareWater\" href=\"petcare.php?pet=#&action=#\">Water Your Pet</a>
<a class=\"petcarePlay\" href=\"petcare.php?pet=#&action=#\">Play With Your Pet</a>
NOW, everything that I listed above works like a charm! This is my problem: I want those links to also update another DIV - the one which contains updated status bars showing how hungry/thirsty/unhappy their pet is. Currently, I am doing that like this:
The Almost Working Script
$(function() {
$(".petcareFood").click(function(event) {
event.preventDefault();
$('#petcareHunger').load('ajax/hunger.php?pet=#');
});
});
$(function() {
$(".petcareWater").click(function(event) {
event.preventDefault();
$('#petcareThirst').load('ajax/thirst.php?pet=#');
});
});
$(function() {
$(".petcarePlay").click(function(event) {
event.preventDefault();
$('#petcareMood').load('ajax/mood.php?pet=#');
});
});
The script above makes it so that when a user clicks one of the HTML links, it updates two DIVS (one DIV containing the message displayed when a user feeds/waters/plays with their pet, and the other containing the status bar). Now... that seems all fine well and good, BUT... if both scripts update at exactly same time, then the PHP that handles the status bar is not updated - it's still retrieving old information.
My question to all of you is: Is there any way that I can delay running the second set of script (so that it will update after the PHP makes changes to MySQL)?
I tried inserting this before "the almost working script":
setTimeout(function() {
$('#petcareMood').load('ajax/mood.php?pet=#');
}, 2000);
However, it doesn't work. Well - it does, but just once. Users need to play with their pets at least 3 times a day to achieve 100% happiness, and so delaying the second DIV only once doesn't cut it for me. When I tried adding the same script multiple times, it just stopped working all together. What can I do?!
If you'd like to see screen shots of how things are working, please just ask. I will be happy to provide them upon request.
Thank you in advance!
Instead of a hardcoded delay time, you maybe could use the callback function of the first ajax action:
//trigger first ajax
$("#petcarePlay").load($(this).attr("href"), function(){
//trigger second ajax call, when first is completed
$('#petcareHunger').load('ajax/hunger.php?pet=#');
});
see http://api.jquery.com/load/
You could use the complete parameter to specify a callback function that gets executed when the request completes. Then from within the callback, execute another request which actually updates the divs.
Example:
$(".petcareWater").click(function(event) {
event.preventDefault();
$("#petcareWater").load($(this).attr("href"), function(response, status, xhr) {
// code here to make another request for stats
}
});
Alternatively, you could have the initial URLs return some JSON data that contain the updated stats so when a person does something to/with their pet, it returns all the stats so you can immediately update the div's all with one call rather than having to make a secondary call for the data.
I'm not sure, but i think the ajax constructor is better for your purpose http://api.jquery.com/jQuery.ajax/.
There you can set that the AJAX will be synchronous(It will wait to finish the AJAX callback )
Here is a few theory about it :)
http://javascript.about.com/od/ajax/a/ajaxasyn.htm
Instead of setTimeout, use setInterval. When it's no longer needed, you can kill it using clearInterval.
setInterval will execute a given function every n milliseconds.

POSTing data to the server, behind the scenes

I'm building a website which has a page that users can add content to, and they can rearrange the divs to whichever position and size they want. I'd like to have a save button which saves the current position of each div; however, I don't want the page to refresh each time (I'm also going to have an auto-save, which will have to save the information in the background).
I can't figure out how to post the data to the server though, without causing the page to reload. I figure I need some kind of AJAX request, but can't find anything that tells me how to do that (all the AJAX examples I can find seem to be about reading data from the server). I think I'm just starting to go round in circles now, but I can't get my head around this at all - I know it's probably not a hard thing to do, but I keep getting confused by the different examples.
So, first of all, is this the best way to do it? And, if so, can someone point me to a straightforward example of posting data via AJAX? I'm already using jQuery, so can use that for the Ajax as well.
Thanks.
Super simple AJAX with jQuery:
$.ajax({
url: '/save-the-stuff-url',
type: 'POST',
data: {
// information about your divs, etc.
'foo' : 'bar'
},
success: function(response) {
// if the AJAX call completes successfully, this function will get called.
alert('POST successful!');
}
});
Give it a shot!
Here, try this for AJAX:
$.post("example.php", {
from : "ajax", // put some info in these - they are the params
time : "2pm",
data : "save"
},
function(data) { // callback function - data always passed to it
$("#success").html(data); // do something with that data
}
);
And put this somewhere:
<span id='success'></span>
And then, try this example for example.php:
<?php
if(isset($_POST['from']) and $_POST['from'] == 'ajax'){
echo "<span style='color: green;'>Saved!</span>";
}
else {
echo "<span style='color: red;'>Failure!</span>";
}
?>
And then just modify these to fit your needs, probably changing the file of target. Whatever the script outputs is what is given to the ajax request. This means that if this was my PHP script:
<?php echo "Aloha!"; ?>
And this was my javascript:
$("#output").load("myScript.php");
Then #output would have "Aloha!" in it.
Hope this helps!
Please go through the Jquery site for various examples of post.
HTH
and the jQuery docs pages are a great way to learn jQuery.. the page for post is http://docs.jquery.com/Post
you may also want to look at jQuery draggables if you're not using that yet..
http://docs.jquery.com/UI/API/1.8/Draggable
you can fire a save tied to your draggable object being let go rather easily with
$( ".selector" ).draggable({
stop: function(event, ui) { ... }
});

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