解析不使用Swift的PFSubclassing

Question

我复制了用于子类的Parse Swift示例：

class Armor : PFObject, PFSubclassing {

    override class func load() {
        self.registerSubclass()
    }
    class func parseClassName() -> String! {
        return "Armor"
    }
}

我得到以下错误：

/Parse/Armor.swift:11:1: error: type 'Armor' does not conform to protocol 'PFSubclassing'
class Armor : PFObject, PFSubclassing {
^
__ObjC.PFSubclassing:15:28: note: protocol requires function 'object()' with type '() -> Self!'
  @objc(object) class func object() -> Self!
                           ^
__ObjC.PFSubclassing:23:52: note: protocol requires function 'objectWithoutDataWithObjectId' with type '(String!) -> Self!'
  @objc(objectWithoutDataWithObjectId:) class func objectWithoutDataWithObjectId(objectId: String!) -> Self!
                                                   ^
__ObjC.PFSubclassing:30:27: note: protocol requires function 'query()' with type '() -> PFQuery!'
  @objc(query) class func query() -> PFQuery!
                          ^
__ObjC.PFSubclassing:35:38: note: protocol requires function 'registerSubclass()' with type '() -> Void'
  @objc(registerSubclass) class func registerSubclass()
                                     ^
/Parse/Armor.swift:14:9: error: 'Armor.Type' does not have a member named 'registerSubclass'
        self.registerSubclass()
        ^    ~~~~~~~~~~~~~~~~

我看到了这个答案：https://stackoverflow.com/a/24899411/843151并尝试了这个解决方案，没有运气，我得到了同样的错误。

对为什么会发生这种事有什么建议吗？提前谢谢。

Answer 1

我需要在目标-C桥接头中导入解析PFObject+Subclass.h。

#import <Parse/PFObject+Subclass.h>

Answer 2

使用xCode 6.1.1，我能够在不使用桥接头的情况下实现这个功能。只是：

import Parse 

在舱顶。对于类声明，我确实需要对变量类型使用@NSManaged来使它们成功地链接到Parse类变量。如下所示：

class PSCategory : PFObject, PFSubclassing {
    override class func load() {
        self.registerSubclass()
    }
    class func parseClassName() -> String! {
        return "Category"
    }

    @NSManaged var Name: String
}

然后，在我的查询中，所有的名称都被动态链接：

var query = PSCategory.query() // PFQuery(className: "Category")

query.cachePolicy = kPFCachePolicyCacheElseNetwork // kPFCachePolicyNetworkElseCache
query.maxCacheAge = 60 * 60 * 24  // One day, in seconds.
query.findObjectsInBackgroundWithBlock {
    (categories: [AnyObject]!, error: NSError!) -> Void in
    if error == nil {
        for abstractCategory in categories {
            let category = abstractCategory as PSCategory

            NSLog("Category Name: %@", category.Name)
        }
    } else {
        NSLog("Unable to retrieve categories from local cache or network")
    }
}

Answer 3

解析建议初始化()而不是load()

class Armor : PFObject, PFSubclassing {
  override class func initialize() {
    var onceToken : dispatch_once_t = 0;
    dispatch_once(&onceToken) {
      self.registerSubclass()
    }
  }

  static func parseClassName() -> String! {
     return "Armor"
  }
}