ios - findObjectsInBackgroundWithBlock 查询成功后返回 nil

Question

我当前的问题是我的 -findObjectsInBackgroundWithBlock 方法对于成功的查询返回 nil 。

我的自定义类是一个 JSON，它是使用 {results: [{}]} 语法导入的。我的 JSON 中有 22 个字典 - {结果:[ 22 个字典]}。我的自定义类在“let query...”声明中正确声明和拼写。当我运行代码时，“print(query)”行输出“PFQuery: 0x7faadb527f40”，所以我假设查询成功？我所说的成功是指查询识别出我的解析站点上有一个名为“BarLibrary”的类 - 确实存在。

使用下面的代码如果我更改 [PFObject]？到[任何对象]？我收到分段 11 错误。与[PFObject]？作为 -findObjectsInBackgroundWithBlock 中“对象”的类型，我总是得到一个零。

我的目标是成功从 parse.com 提取 JSON 数据并将其存储到“对象”中。

My Class Name and # of items in JSON as seen on my parse account

我的自定义 JSON 中的数据结构如下:

{ 
"results" :  [{
        "name": String,
        "address": String,
        "image": String,
        "latitude" : double,
        "longitude" : double,

        "Monday" : {   "key1": String,
            "key2":String,
            "key3": 16,
            "key4": 19,
            "key5": 999,
            "key6": 999,
            "key7": String,
            "key8": String
        },
        "Tuesday" : {   "key1": String,
            "key2":String,
            "key3": 16,
            "key4": 19,
            "key5": 999,
            "key6": 999,
            "key7": String,
            "key8": String
        },
        "Wednesday" : {   "key1": String,
            "key2":String,
            "key3": 16,
            "key4": 19,
            "key5": 999,
            "key6": 999,
            "key7": String,
            "key8": String
        },
        "Thursday" : {   "key1": String,
            "key2":String,
            "key3": 16,
            "key4": 19,
            "key5": 999,
            "key6": 999,
            "key7": String,
            "key8": String
        },
        "Friday" : {   "key1": String,
            "key2":String,
            "key3": 16,
            "key4": 19,
            "key5": 999,
            "key6": 999,
            "key7": String,
            "key8": String
        },
        "Saturday" : {   "key1": String,
            "key2":String,
            "key3": 16,
            "key4": 19,
            "key5": 999,
            "key6": 999,
            "key7": String,
            "key8": String
        },
        "Sunday" : {   "key1": String,
            "key2":String,
            "key3": 16,
            "key4": 19,
            "key5": 999,
            "key6": 999,
            "key7": String,
            "key8": String
        }
          ...... // 22 total dictionaries like this in the array "results"

有人能指出我正确的方向吗？

import Foundation
import Parse


struct getBarJSON {

init(){

    let query : PFQuery = PFQuery(className: "BarLibrary")
    print("\n")
    print("Result of the query")
    print("=========================")
    print(query) // <PFQuery: Hex Number>

    query.findObjectsInBackgroundWithBlock {(objects : [PFObject]?, error: NSError? )-> Void in

        if error == nil {
            // Do something upon successfull network request
            print("\n")
            print("Result of Network Request")
            print("=========================")

            if let objects = objects as [PFObject]! {
                    print(objects)
                }

        } else {
            // Report the error
            print("\n")
            print("Error Description:")
            print("==================")
            print(error)
        }
       }
      }
     }

Answer 1

这是从查询中获取对象的正确方法。如果你仍然得到 nil，那么你应该检查你的“BarLibrary”类表的数据(也许在这里发布示例内容，以便理解其结构)当前登录打印出 PFObjects，无论它们的属性如何。

import Foundation
import Parse


struct getBarJSON {

init(){

    let query = PFQuery(className: "BarLibrary")

    query.findObjectsInBackgroundWithBlock {(objects : [PFObject]?, error: NSError? )-> Void in
        print("\n")
        print("Result of Network Request")
        print("=========================")
        if error == nil {
            print("\n")
            print("Result of the query")
            print("=========================")

            if let objects = objects {   // unwrapping an optional
                for object in objects {  // iterating over the array of pfobjects
                    print(object)
                    if let customObject = object["someProperty"] as? String { // in case you store a string. The process in similar for numbers, arrays, etc.
                      print(customObject.characters.count)
                    }
                }
            }

        } else {
            // Report the error
            print("\n")
            print("Error Description:")
            print("==================")
            print(error)
        }
       }
      }
     }