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Questions tagged [jquery-deferred]

jQuery's deferred (also known as promises and futures) can be used to manage callback queues

jQuery.Deferred(), introduced in version 1.5, is a chainable utility object that can register multiple callbacks into callback queues, invoke callback queues, and relay the success or failure state of any synchronous or asynchronous function.

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jQuery Deferred: Rejecting a Promise from within a Done Filter

Fyi, I'm just starting to learn jQuery promises, so I may be a bit confused here. Anyway, I have an AJAX request that I want to reject from within a done filter based on the content of the response: return doAJAXRequest().then(function (data) { …
Ajedi32
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jQuery Deferred's, $.when() and the fail() callback arguments

I'm getting an unexpected result when using $.when() when one of the deferred operations does not succeed. Take this JavaScript, which created 2 deferreds. The first one succeeds and the second one fails. var f1 = function() { return…
Alex Wayne
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When should I reject a promise?

I'm writing some JS code that uses promises. For example, I open a form pop-up and I return a jQuery Deferred object. It works like this: If the user clicks OK on the form, and it validates, the Deferred resolves to an object representing the form…
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How to use jQuery Deferred with custom events?

I have two abstracted processes (e.g. managed within js objects using the revealing module pattern that do not expose their internals) that fire custom events when they complete. I want to perform an action when both custom events have fired. The…
Adam Flynn
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Using jQuery load with promises

I'm still trying to wrap my head around deferred and what not, so with this in mind I have a question on how to do the following. My team and I have 3 separate .load() methods that each go grab a specific template and append that to the same…
Mike Fielden
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Return an empty promise

I have a function that returns a jQuery promise. It looks like this: addBooks(books: Array) { return $.ajax({ url: '/Books/AddBooks/', type: 'POST', data: ko.toJSON(books), contentType: 'application/json' …
Jonathan Eckman
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Asynchronous Loop of jQuery Deferreds (promises)

I am trying to create what I think is referred to as a "Waterfall". I want to sequentially process an array of async functions (jQuery promises). Here's a contrived example: function doTask(taskNum){ var dfd = $.Deferred(), time =…
Jon Wells
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jQuery $.when() with variable arguments

I want to send [1, n) AJAX-requests to the server and after all have returned a result a modal dialog should be closed. $.when(a(), b(), c()) would be perfect, but I don't know how to pass the variable count of functions to $.when as parameter. Any…
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in JavaScript, how to wrap a promise in timeout?

It's a common pattern to implement timeout of some asynchronous function, using deffered/promise: // Create a Deferred and return its Promise function timeout(funct, args, time) { var dfd = new jQuery.Deferred(); // execute asynchronous…
mnowotka
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How do I chain a sequence of deferred functions in jQuery 1.8.x?

Given these functions: function func1() { var dfd = $.Deferred(); setTimeout(function() { dfd.resolve('Password'); }, 1000); return dfd.promise(); } function func2(message) { var dfd = $.Deferred(); setTimeout(function() { if…
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Understanding Deferred.pipe()

I've been reading about deferreds and promises in jQuery but I haven't used it yet. I've understood everything very well but the method pipe. I really didn't get what it is. Could some please help me to understand what it does and where could it be…
Diego
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Waiting for jQuery AJAX response(s)

I have a page that, using jQuery .ajax that is called 100 times (async: true), the problem is that, when they they are all being loaded, I need the system to wait for ALL 100 calls to return before continuing. How would I go about this? Thanks in…
Olive
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jQuery deferred object with nested ajax calls

I have a situation in which my ajax calls must perform in a particular order. I have used jQuery Deferred objects in other situations, but cannot seem to find a way to make this behave appropriately. I have a function which performs a number of ajax…
Aesthete
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jQuery Deferred vs jqXHR

I use: var jqXHR = $.ajax(settings); jqXHR.success(function(result){}); jqXHR.error(function(result){}); jqXHR.complete(function(result){}); But version 1.5 has added the deferred object. Q: In general, when do you use success, error and complete…
Phillip Senn
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JQuery Deferred. Using $.when and .progress()

I am writing a parser littered with Async Tasks. I use JQuery promises to control and order the async tasks. This is a psuedo code version of the constructor function: /** * @constructor */ function Parser(json) { …
Jon Wells
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