ios - Parse.com 查询以获取具有特定指针的所有项目

Question

我想从我的 Parse.com 表(名为 Sticker)中的特定商店获取所有商品。我的 Sticker 表有一个名为 shopId 的列。所以显而易见的解决方案是这样的:

//get all stickers from one shop of category dress
        var query = PFQuery(className:"Sticker")
        query.whereKey("shopId", equalTo: "QjSbyC6k5C")
        query.whereKey("category", equalTo: "DR")
        query.findObjectsInBackgroundWithBlock {
            (objects: [AnyObject]?, error: NSError?) -> Void in

            if error == nil {
                // The find succeeded.
                println("Successfully retrieved \(objects!.count) scores.")
                // Do something with the found objects
                if let objects = objects as? [PFObject] {
                    for object in objects {
                        println(object.objectId)
                    }
                }
            } else {
                // Log details of the failure
                println("Error: \(error!) \(error!.userInfo!)")
            }
        }

但是这会导致此错误:

error: pointer field shopId needs a pointer value

我看到一个常见的解决方案似乎是向查询传递实际对象而不是 ID 字符串。这是否意味着我必须首先执行单独的查询来获取特定的商店对象，然后将其传递给我的查询？或者有更短的方法吗？

这是我尝试获取商店的方法，但它导致了此错误:

Can only call -[PFObject init] on subclasses conforming to PFSubclassing

var query1 = PFQuery(className: "Shop")
        var shop1 = PFObject()
        query1.getObjectInBackgroundWithId("QjSbyC6k5C") {
            (shop: PFObject?, error: NSError?) -> Void in
            shop1 = shop!
        }

编辑:所以我的解决方案基本上是按照答案的建议进行操作。我的代码是这样的(魅力是商店的名称):

var shopQuery = PFQuery(className:"Shop")
        shopQuery.getObjectInBackgroundWithId("QjSbyC6k5C") {
            (glamour: PFObject?, error: NSError?) -> Void in
            if error == nil && glamour != nil {
                println(glamour)

                //get all stickers from one shop of category dress
                var query = PFQuery(className:"Sticker")
                query.whereKey("shopId", equalTo: glamour!)
                query.whereKey("category", equalTo: "DR")
                query.findObjectsInBackgroundWithBlock {
                    (objects: [AnyObject]?, error: NSError?) -> Void in

                    if error == nil {
                        // The find succeeded.
                        println("Successfully retrieved \(objects!.count) scores.")
                        // Do something with the found objects
                        if let objects = objects as? [PFObject] {
                            for object in objects {
                                println(object.objectId)
                            }
                        }
                    } else {
                        // Log details of the failure
                        println("Error: \(error!) \(error!.userInfo!)")
                    }
                }
            } else {
                println(error)
            }
        }

我会把这个问题留在这里，也许有人会用评论来回答:有没有办法获取商店并赋予它类范围，这样我们就不必将第二个查询嵌套在成功的第一个查询？这样会更优雅吗？

Answer 1

您需要传递 PFObject。使用以下代码更改您的代码

PFObject *object = ...
    var query = PFQuery(className:"Sticker")
    query.whereKey("shopId", equalTo: "QjSbyC6k5C")
    query.whereKey("category", equalTo: object);