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Asynchronous call confirmation dialog in event

I want to return a boolean value from a jQuery confirmation dialog and return that value to an event (to either continue or stop default execution of an event). I know about asynchronous calls but I really can't get around this. This is what I have until now:
function moveConfirmation() {
var defer = $.Deferred();
$('#dialog-move-confirm').dialog({
resizable: false,
width: 400,
height: 200,
autoOpen: true,
modal: true,
buttons: {
'Move Separately': function() {
$(this).dialog('close');
defer.resolve(true);
},
'Move Together': function() {
$(this).dialog('close');
defer.resolve(false);
},
Cancel: function() {
$(this).dialog('close');
defer.resolve(false);
}
}
});
return defer.promise();
}
scheduler.attachEvent('onBeforeEventChanged', function(id, ev) {
// if move contemporaneous exams, alert user to choose if move together or separately
var state = scheduler.getState();
var saveEvent = false;
if (state.drag_mode === 'move') {
moveConfirmation().then(function(move) {
saveEvent = move;
});
}
return saveEvent;
}
What is happening is that saveEvent is still false and returning before the promise. What should I do? I also tried another promise.. but it still comes back to the same thing. Anyone sees a workaround for this?

You must know that the return statement within onBeforeEventChanged will always return false, since moveConfirmation().then(...) is async.
You will probably have to always cancel the onBeforeEventChanged event like you are doing, but rather than simply setting saveEvent = move; within the moveConfirmation handler, you will have to re-trigger the attempted operation programmatically in case the user wanted to proceed (perhaps using updateEvent).
Please also note that you need a mechanism in place to avoid having the re-triggering process to invoke your dialog box again (e.g. if onBeforeEventChanged is fired when calling updateEvent).
EDIT: Note that you can also do the opposite if it looks better on the UI, always accept event changes, but undo them if needed as per the moveConfirmation's response.

stop and later persue javascript event in jquery ui modal dialog

I want to stop an event show a modal dialog and if the user presses yes persue this event. event.run() brings an error in firefox.
jQuery(element).click(function(event) {
event.preventDefault();
dialog.dialog({
buttons: {
'Ja': function() {
event.run();
},
'Nein': function() {
jQuery(this).dialog('close');
}
}
}).dialog('open');
});
Thanks to a friend and hashbrown I managed to solve this problem. An event cannot be paused and persued. If it is paused it will block the whole DOM. Try:
jQuery(link).click(function(){while(true)});
When using jQuery its possible to set additional event parameters what I did:
jQuery(element).click(function(event, show_dialog) {
var that = jQuery(this);
if(!show_dialog) {
dialog.dialog({
buttons: {
'Yes': function() {
that.trigger(event.type, [true]);
},
'No': function() {
jQuery(this).dialog('close');
}
}
}).dialog('open');
return false;
} else {
dialog.dialog('close');
return true;
}
});
First click show_dialog is undefined and modal dialog is shown. Clicking on Yes in modal dialog triggers the event.type (click) with the additional parameter true for show_dialog. http://api.jquery.com/trigger/#trigger-eventType-extraParameters
It was not possible to that.trigger(event, [true]);. I think cause events default action was prevented before.

That is because immediately after creating the popup the function returns and the event expires.
What you'll have to do is .trigger() a new event.
Note: set some sort of global variable to ignore this second event firing in your anonymous function (infinite loop problem).
Can I ask why you want to do this; what would click go off and do if you let it?
If it just fires off a different function, why not just call that function instead of attempting event.run()?

Callbacks running twice after AJAX content loaded

I have a page loading content with the waypoints infinite scroller plugin.
On the success of the AJAX call and after DOM elements are added, a callback runs to re-initilize javascript functionality, like carousels, buttons and other animation.
On the first AJAX call, buttons tasked with toggling work properly. On the next AJAX call, the new DOM items work, but the previous buttons now execute toggles twice when clicked. On the third call, original items now run three times, the second items twice and the new ones once, so on and so fourth, continuing to compound as AJAX content is called.
How can I isolate the callback to not affect the previously loaded content, or, is there a way to set a global state for the JS, so that I don't need the callback each time?
Some pseudo code:
$('.infinite-container').waypoint('infinite', {
onAfterPageLoad: function() {
//Carousel options
$('.carousel-container').carousel({
options: here,
....
});
//Button Toggles
$('.button').click(function(){
var self = $(this);
$(this).siblings('.caption').animate({
height: 'toggle'
}, 200, function() {
// Callback after animate() completes.
if(self.text() == 'Hide Details'){
self.text('Show Details');
} else {
self.text('Hide Details');
}
});
});
}
});
Edit: Thanks everybody. All the answers lead me to differing but appropriate solutions. The selected was picked as it's a great collection of all the suggested issues and worth the read.

Check out this answer. I think it is the same situation you are having and has a solution:
Best way to remove an event handler in jQuery?

You are attaching a new click handler each time that block of code gets executed. The result is multiple click handlers being bound to your button. Use jQuery's unbind: http://api.jquery.com/unbind/ to remove any click handler(s) before adding a new one:
$('.infinite-container').waypoint('infinite', {
onAfterPageLoad: function() {
//Carousel options
$('.carousel-container').carousel({
options: here,
....
});
// Un-bind click handler(s)
$('.button').unbind('click');
//Button Toggles
$('.button').click(function(){
var self = $(this);
$(this).siblings('.caption').animate({
height: 'toggle'
}, 200, function() {
// Callback after animate() completes.
if(self.text() == 'Hide Details'){
self.text('Show Details');
} else {
self.text('Hide Details');
}
});
});
}
});

Try bind only once click event to button. Of course you can use on instead of live.
$('.button').live('click', function(){
var self = $(this);
$(this).siblings('.caption').animate({
height: 'toggle'
}, 200, function() {
// Callback after animate() completes.
if(self.text() == 'Hide Details'){
self.text('Show Details');
} else {
self.text('Hide Details');
}
});
});
$('.infinite-container').waypoint('infinite', {
onAfterPageLoad: function() {
//Carousel options
$('.carousel-container').carousel({
options: here,
....
});
//Button Toggles
}
});

$('.button').click(function(){
You add an event handler to every button that has the class button. When the second button is added then you add it to every ... which means button 1 and button 2. And so on.
Try
$('.button').last().click(function(){

Filling multiple divs with single ajax() call, form submit button fails

The short question is when I fill a <div> containing a type=submit button the .click(function(){...} function fails.
What I'm doing is this, #formDialogButton opens #accordion populated by .ajax() containing #userForm with an input type=submit. When client clicks submit it is supposed to fire .ajax() where php does database stuff and returns one of the #userform.
$(".formDialogButton").click(function(){
var userDialog = "#" + this.id + "Dialog";
$("#userForm, #siteForm, #limitForm").html("<img src='ajax-loader.gif' />");
$("#userForm, #siteForm, #limitForm").load("ajax.php", {op: "forms"}, function(responseTxt,statusTxt,xhr){
$("#userForm").html($("#user").html());
$("#siteForm").html($("#site").html());
$("#limitForm").html($("#limit").html());
if(statusTxt=="success") {
$(userDialog).dialog({
autoOpen: false,
draggable: true,
modal: true,
resizable: true,
width: 700,
position: { within: "#mainContent" }
});
$(userDialog).dialog("open");
$( "#accordion").accordion({
collapsible: true,
heightStyle: "content",
});
};
if(statusTxt =="error")
alert("Error: "+xhr.status+": "+xhr.statusText);
});
});
This is working and returns a <input class="submitAndReturn" type="submit" value="Submit" /> in the form. But I can't "find" it to do anything.
$(".submitAndReturn").click(function() {
alert ('this is where I call my regular .formSubmitButton and let success: function() do a .formDialogButton ');
});
I'm a total self taught amateur so please forgive me and try to help. Thanks

Sounds like you are trying to add the click event before the element is loaded on the page. Change
$(".submitAndReturn").on("click", function() {
alert ('as .submit and return is dynamically loaded. so, use on function');
});
to
$(document).on("click", ".submitAndReturn", function(e) {
e.preventDefault(); //cancel the click action if needed
alert ('as .submit and return is dynamically loaded. so, use on function');
});

$(".submitAndReturn").on("click", function() {
alert ('as .submit and return is dynamically loaded. so, use on function');
});

What I'm doing is this, #formDialogButton opens #accordion populated by .ajax() containing #userForm with an input type=submit
If I understand it correct .formDialogButton DOM element is getting loaded in .ajax() callback event.
If you are loading the javascript in question above in header or at the page end, most likely the $(".formDialogButton").click(function() event is not getting attached to DOM.
This happens because the script has already fired before the AJAX has fetched the required DOM to which event has to be attached. You would need to attach the event in .ajax() success callback. Something like
$.ajax({
url: 'YOUR_URL_TO_FETCH_FORM',
success: function(data) {
// associate click
$(".formDialogButton").click(function() // rest of the code
}
});

Change the asynchronous jQuery Dialog to be synchronous?

Currently, I'm working to replace "alert'/"confirm" with the jquery dialog.
But most of legacy codes is written in some asynchronous way, which make it difficult to change. Is there any way to make jquery dialog work in a synchronous way? ( don't use loop or callback function )
For example:
function run()
{
var result = confirm("yes or no");
alert( result );
\\more codes here
}
In this example the alert and other codes will be executed after user's choice.
If we use jquery dialog
var result = $dialog.open()
It will continue to execute the alert, which is asynchronous.
Currently, my solution is to use call back function in the OK|Cancel function.
For example:
OK: function ()
{
$dialog.close();
alert("yes");
//more codes here
}
This method works but it is difficult to make all the synchronous codes become asynchronous, which requires a lot of change (see the following example). So I'm looking for the synchronous jQuery Dialog, is it possible??
For example: ( The real codes are much more complicated than the following example)
function f1()
{
if ( confirm("hello") ) f2();
alert("no");
}
function f2()
{
if( confirm("world") ) f3();
alert("no");
}
function f3()
{
return confirm("!") ;
}
Another example:
vendorObject.on('some-event', function() {
if(confirm("Do you really want to do that?")) {
return true;
}
else {
return false; // cancel the event
}
});
... here the vendor object fires an event, which has to be cancelled if the user confirms. The event can only be cancelled if the event handler returns false - synchronously.

The short answer is no, you won't be able to keep your code synchronous. Here's why:
In order for this to be synchronous, the currently executing script would have to wait for the user to provide input, and then continue.
While there is a currently executing script, the user is unable to interact with the UI. In fact, the UI doesn't even update until after the script is done executing.
If the script can't continue until the user provides input, and the user can't provide input until the script is finished, the closest you'll ever get is a hung browser.
To illustrate this behavior, debug your code and set a break point on the line following a line that changes the UI:
$("body").css("backgroundColor", "red");
var x = 1; // break on this line
Notice that your page background is not yet red. It won't change to red until you resume execution and the script finishes executing. You are also unable to click any links in your page while you've got script execution paused with your debugger.
There is an exception to this rule for alert() and confirm(). These are browser controls, and are treated differently than actual web page UI elements.
The good news is that it really shouldn't be very hard to convert your code. Presumably, your code currently looks something like this:
if (confirm("continue?")) {
// several lines of code if yes
}
else {
// several lines of code if no
}
// several lines of code finally
Your asynchronous version could create a function ifConfirm(text, yesFn, noFn, finallyFn) and your code would look very much the same:
ifConfirm("continue?", function () {
// several lines of code if yes
},
function () {
// several lines of code if no
},
function () {
// several lines of code finally
});
Edit: In response to the additional example you added to your question, unfortunately that code will need to be refactored. It is simply not possible to have synchronous custom confirmation dialogs. To use a custom confirmation dialog in the scenario where an event needs to either continue or cancel, you'll just have to always cancel the event and mimic the event in the yesFn callback.
For example, a link:
$("a[href]").click(function (e) {
e.preventDefault();
var link = this.href;
ifConfirm("Are you sure you want to leave this awesome page?", function () {
location.href = link;
});
});
Or, a form:
$("form").submit(function (e) {
e.preventDefault();
var form = this;
ifConfirm("Are you sure you're ready to submit this form?", function () {
form.submit();
});
});

I'm not exactly sure what the motivation behind not using callbacks is so it is hard to judge what solution might satisfy your requirements, but another way to delay execution is through jQuery's "deferred" object.
http://api.jquery.com/category/deferred-object/
You could set up a function that opens the jquery dialog and add code that "waits" for dialog to close. This ends up working in a fairly similar way to a callback in the case you've laid out but here is an example:
function confirm () {
var defer = $.Deferred();
$('<div>Do you want to continue?</div>').dialog({
autoOpen: true,
close: function () {
$(this).dialog('destroy');
},
position: ['left', 'top'],
title: 'Continue?',
buttons: {
"Yes": function() {
defer.resolve("yes"); //on Yes click, end deferred state successfully with yes value
$( this ).dialog( "close" );
},
"No": function() {
defer.resolve("no"); //on No click end deferred successfully with no value
$( this ).dialog( "close" );
}
}
});
return defer.promise(); //important to return the deferred promise
}
$(document).ready(function () {
$('#prod_btn').click(function () {
confirm().then(function (answer) {//then will run if Yes or No is clicked
alert('run all my code on ' + answer);
});
});
});
Here it is working in jsFiddle: http://jsfiddle.net/FJMuJ/

No, you can't do anything sync in Javascript (alert is breaking the rules, in fact). Javascript is built with "single threaded, async" in the core.
What you can do, though, is disable functionality of the underlying page (lightbox-like) so no event get triggered from the page until you don't take the dialog action, be it OK or Cancel. Thought this does not help you to get your sync code working. You have to rewrite.

Here's some ideas - what you actually want is to block your async event to make it look like sync. Here's some links:
Queuing async calls
Mobl
Narrative JavaScript
Hope this helps you further!!

To answer David Whiteman's more specific question, here's how I'm implementing a "deferred" postback for a LinkButton Click event. Basically, I'm just preventing the default behaviour and firing the postback manually when user feedback is available.
function MyClientClickHandler(event, confirmationMessage, yesText, noText) {
// My LinkButtons are created dynamically, so I compute the caller's ID
var elementName = event.srcElement.id.replace(/_/g, '$');
// I don't want the event to be fired immediately because I want to add a parameter based on user's input
event.preventDefault();
$('<p>' + confirmationMessage + '</p>').dialog({
buttons: [
{
text: yesText,
click: function () {
$(this).dialog("close");
// Now I'm ready to fire the postback
__doPostBack(elementName, 'Y');
}
},
{
text: noText,
click: function () {
$(this).dialog("close");
// In my case, I need a postback when the user presses "no" as well
__doPostBack(elementName, 'N');
}
}
]
});
}

You can use a real modal dialog.
[dialog] is an element for a popup box in a web page, including a modal option which will make the rest of the page inert during use. This could be useful to block a user's interaction until they give you a response, or to confirm an action.
https://github.com/GoogleChrome/dialog-polyfill

I don't really see why you are opposed to using Jquery callbacks to achieve the behavior in your example. You will definitely have to rewrite some code but something like:
function f1() {
$( "#testdiv" ).dialog({
modal: true,
buttons: {
"OK": function() {
$( this ).dialog( "close" );
f2();
},
Cancel: function() {
$( this ).dialog( "close" );
alert('no');
}
}
});
}
function f2() {
$( "#testdiv2" ).dialog({
modal: true,
buttons: {
"OK": function() {
$( this ).dialog( "close" );
f3();
},
Cancel: function() {
$( this ).dialog( "close" );
alert('no');
}
}
});
}
function f3() {
$( "#testdiv3" ).dialog({
modal: true,
buttons: {
"OK": function() {
$( this ).dialog( "close" );
},
Cancel: function() {
$( this ).dialog( "close" );
}
}
});
}
<div id="testdiv" title="Hello"/>
<div id="testdiv2" title="World"/>
<div id="testdiv3" title="!"/>