lib/dojo/DeferredList.js

   1 /*
   2         Copyright (c) 2004-2010, The Dojo Foundation All Rights Reserved.
   3         Available via Academic Free License >= 2.1 OR the modified BSD license.
   4         see: http://dojotoolkit.org/license for details
   5 */
   6
   7
   8 if(!dojo._hasResource["dojo.DeferredList"]){ //_hasResource checks added by build. Do not use _hasResource directly in your code.
   9 dojo._hasResource["dojo.DeferredList"] = true;
  10 dojo.provide("dojo.DeferredList");
  11 dojo.DeferredList = function(/*Array*/ list, /*Boolean?*/ fireOnOneCallback, /*Boolean?*/ fireOnOneErrback, /*Boolean?*/ consumeErrors, /*Function?*/ canceller){
  12         // summary:
  13         //              Provides event handling for a group of Deferred objects.
  14         // description:
  15         //              DeferredList takes an array of existing deferreds and returns a new deferred of its own
  16         //              this new deferred will typically have its callback fired when all of the deferreds in
  17         //              the given list have fired their own deferreds.  The parameters `fireOnOneCallback` and
  18         //              fireOnOneErrback, will fire before all the deferreds as appropriate
  19         //
  20         //      list:
  21         //              The list of deferreds to be synchronizied with this DeferredList
  22         //      fireOnOneCallback:
  23         //              Will cause the DeferredLists callback to be fired as soon as any
  24         //              of the deferreds in its list have been fired instead of waiting until
  25         //              the entire list has finished
  26         //      fireonOneErrback:
  27         //              Will cause the errback to fire upon any of the deferreds errback
  28         //      canceller:
  29         //              A deferred canceller function, see dojo.Deferred
  30         var resultList = [];
  31         dojo.Deferred.call(this);
  32         var self = this;
  33         if(list.length === 0 && !fireOnOneCallback){
  34                 this.resolve([0, []]);
  35         }
  36         var finished = 0;
  37         dojo.forEach(list, function(item, i){
  38                 item.then(function(result){
  39                         if(fireOnOneCallback){
  40                                 self.resolve([i, result]);
  41                         }else{
  42                                 addResult(true, result);
  43                         }
  44                 },function(error){
  45                         if(fireOnOneErrback){
  46                                 self.reject(error);
  47                         }else{
  48                                 addResult(false, error);
  49                         }
  50                         if(consumeErrors){
  51                                 return null;
  52                         }
  53                         throw error;
  54                 });
  55                 function addResult(succeeded, result){
  56                         resultList[i] = [succeeded, result];
  57                         finished++;
  58                         if(finished === list.length){
  59                                 self.resolve(resultList);
  60                         }
  61
  62                 }
  63         });
  64 };
  65 dojo.DeferredList.prototype = new dojo.Deferred();
  66
  67 dojo.DeferredList.prototype.gatherResults= function(deferredList){
  68         // summary:
  69         //      Gathers the results of the deferreds for packaging
  70         //      as the parameters to the Deferred Lists' callback
  71
  72         var d = new dojo.DeferredList(deferredList, false, true, false);
  73         d.addCallback(function(results){
  74                 var ret = [];
  75                 dojo.forEach(results, function(result){
  76                         ret.push(result[1]);
  77                 });
  78                 return ret;
  79         });
  80         return d;
  81 };
  82
  83 }