for循环内的异步函数（解析查询）

Question

我想从Parse.com获取所有帖子，并检查每个人是否被当前用户喜欢。据我所知，内部查询不能在for循环内完成，因为它是一个异步函数。我不明白如何格式化它的方式，让我检查每个职位。我试过$ q.defer（），但它也没有工作。任何帮助将不胜感激

var imageGallery = Parse.Object.extend("Gallery"); 
var query = new Parse.Query(imageGallery); 

query.include("user"); 
query.near("location", $rootScope.currentLocation); 
query.find({ 
    success: function(results) { 
    var i = 0; 
    for (i; i < results.length; i++) { 
     var object = results[i]; 

     var galleryLike = Parse.Object.extend("GalleryLike"); 
     var likeQuery = new Parse.Query(galleryLike); 

     likeQuery.include('gallery'); 
     likeQuery.include('user'); 
     likeQuery.equalTo('gallery', object); 
     likeQuery.equalTo('user', Parse.User.current()); 
     likeQuery.find({ 
     success: function(res) { 
      if (res.length == 0) { 
      var like = "false"; 
      } else { 
      var like = "true"; 
      } 
     }, 
     error: function(error) { 

     } 
     }); 

     var distance = object.get('location').kilometersTo($rootScope.currentLocation); 

     self.images.push({ 
     object: object, 
     locationName: object.get('locationName'), 
     caption: object.get('caption'), 
     img: object.get('img').url(), 
     username: object.get('user').get('username'), 
     userprofpic: object.get('user').get('profpic').url(), 
     distance: distance, 
     isLiked: like 
     }); 
    } 
    $scope.$apply(); 
    $ionicLoading.hide(); 
    }, 
    error: function(error) { 
    $ionicLoading.hide(); 
    } 
}); 

Answer 1

定义一个函数，它仅得到一个职位，说getPost()并返回一个承诺。 然后你可以使用$q.all()像以下：

var promises = [];  
for (var i < results.length; i++) { 
    promises.push(getPost(i)); 
} 
$q.all(promises) 
    .then(function(results){ 
     // results[i] is relevant to post #i 
    });