jQuery.Deferred() JQ Home  <<  Objects  <<  jQuery.Deferred()

• <<    Callbacks
• deferred.always()     >>

Deferred object creation.

Shorthand version $.Deferred()

Description

The jQuery.Deferred() Deferred Constructor method, creates a Deferred object for managing callback queues.

• Only the creator of a Deferred object should call the deferred.notify(), deferred.notifyWith(), deferred.resolve(), deferred.resolveWith(), deferred.reject() or deferred.rejectWith() methods. Other code can be stopped from changing a Deferred objects state or reporting status by returning a restricted Promise object through the deferred.promise() method.
• After creating a Deferred object, you can use any of the Deferred object methods by chaining directly on object creation, or saving the object to a variable and then invoking the Deferred object methods on that variable.

Syntax

Parameters

Return

A Deferred object.

jQuery.Deferred( [initFunction] ) ExamplesObjects  <<  Top

Create a Deferred object for managing callback queues.

In the example below when we press the button the first time we create a Deferred object and use some deferred object methods on it.

$(function(){
  $('#btn1').one('click', function(){
    var ourDeferred = $.Deferred();
    ourDeferred.always( aFunc );
    ourDeferred.progress( [aFunc, bFunc] );
    ourDeferred.notify( 'The aFunc function was fired from our deferred. <br>', '#div1');
    ourDeferred.resolve( 'Our deferred was resolved. <br><br>', '#div1' );
  });
  function aFunc( value, div ){
    $(div).append( value);
  }
  function bFunc( value, div ){
    aFunc('Passing bFunc function value to aFunc. <br>', div);
  }
});

Create a Deferred object for managing callback queues passing an inititailizing function

In the example below when we press the button the first time we create a Deferred object using an initializing function which calls some deferred object methods on the newly created Deferred object passed to it.

$(function(){
  $('#btn2').one('click', function(){
    var ourDeferred = $.Deferred( initFunc );
  });
  function initFunc( newDeferredObj ){
    newDeferredObj.always( aFunc );
    newDeferredObj.progress( [aFunc, bFunc] );
    newDeferredObj.notify( 'aFunc function fired from deferred init function. <br>', '#div2');
    newDeferredObj.resolve( 'deferred was resolved in the init function. <br>', '#div2' );
  }
  function aFunc( value, div ){
    $(div).append( value);
  }
  function bFunc( value, div ){
    aFunc('Passing bFunc function value to aFunc. <br>', div);
  }
});

Related Tutorials

jQuery Advanced Tutorials - Lesson 7 - The Deferred Object

• <<    Callbacks
• deferred.always()     >>