ios - Swift 4 - 将类结构的 JSON 响应嵌套到 TableViewCell 中

问题描述

我有以下结构来帮助从 JSON Web api 返回数据：

// To parse the JSON, add this file to your project and do:
//
//   let story = try? JSONDecoder().decode(Story.self, from: jsonData)

import Foundation

typealias Story = [StoryElement]

struct StoryElement: Codable {
    let id: Int
    let url: String
    let storyPublic, featured: Bool
    let added, modified: String
    let itemType: ItemType
    let collection: JSONNull?
    let owner: Owner
    let files: Files
    let tags: [ItemType]
    let elementTexts: [ElementText]
    let extendedResources: ExtendedResources

    enum CodingKeys: String, CodingKey {
        case id, url
        case storyPublic = "public"
        case featured, added, modified
        case itemType = "item_type"
        case collection, owner, files, tags
        case elementTexts = "element_texts"
        case extendedResources = "extended_resources"
    }
}

struct ElementText: Codable {
    let html: Bool
    let text: String
    let elementSet: ElementSet
    let element: Element

    enum CodingKeys: String, CodingKey {
        case html, text
        case elementSet = "element_set"
        case element
    }
}

struct Element: Codable {
    let id: Int
    let url, name: String
    let resource: ElementResource
}

enum ElementResource: String, Codable {
    case elements = "elements"
}

struct ElementSet: Codable {
    let id: Int
    let url: URL
    let name: Name
    let resource: ElementSetResource
}

enum Name: String, Codable {
    case dublinCore = "Dublin Core"
    case itemTypeMetadata = "Item Type Metadata"
}

enum ElementSetResource: String, Codable {
    case elementSets = "element_sets"
}

enum URL: String, Codable {
    case httpWWWRalstoncemeteryCOMGreeleyAPIElementSets1 = "http://www.ralstoncemetery.com/greeley/api/element_sets/1"
    case httpWWWRalstoncemeteryCOMGreeleyAPIElementSets3 = "http://www.ralstoncemetery.com/greeley/api/element_sets/3"
}

struct ExtendedResources: Codable {
    let exhibitPages: Files
    let geolocations: Owner

    enum CodingKeys: String, CodingKey {
        case exhibitPages = "exhibit_pages"
        case geolocations
    }
}

struct Files: Codable {
    let count: Int
    let url, resource: String
}

struct Owner: Codable {
    let id: Int
    let url, resource: String
}

struct ItemType: Codable {
    let id: Int
    let url, name, resource: String
}

// MARK: Encode/decode helpers

class JSONNull: Codable {
    public init() {}

    public required init(from decoder: Decoder) throws {
        let container = try decoder.singleValueContainer()
        if !container.decodeNil() {
            throw DecodingError.typeMismatch(JSONNull.self, DecodingError.Context(codingPath: decoder.codingPath, debugDescription: "Wrong type for JSONNull"))
        }
    }

    public func encode(to encoder: Encoder) throws {
        var container = encoder.singleValueContainer()
        try container.encodeNil()
    }
}

您可以在此处查看我正在使用的 JSON 输出以及原始结构：https ://app.quicktype.io?share=oAMNjooSzgpraWpf1KIj （仅供参考）。

数据（我相信）已成功返回并正确解析，唯一的问题归结为我自己不那么熟悉（我正在尝试了解更多信息）。

所以我有一个 TableViewController 并且我有一个单元格，其中包含以下代码：

struct StoryCellViewModel {
    let id: Int
    let url: String
    let storyPublic, featured: Bool
    let added, modified: String
}

在 viewDidLoad() 下的实际 TableViewController 中，我有这部分脚本：

 print(story)
                self.cellViewModels = story.map{
                    StoryCellViewModel(id: $0.id, url: $0.url, storyPublic: $0.storyPublic, featured: $0.featured, added: $0.added, modified: $0.modified)
                }

比这低一点，我有：

override func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
    let cell = tableView.dequeueReusableCell(withIdentifier: "StoryCell", for: indexPath)

    let cellViewModel = cellViewModels[indexPath.row]
    cell.textLabel?.text = String(cellViewModel.id)
    cell.detailTextLabel?.text = cellViewModel.modified


    return cell
}

我会让大家知道所有这些工作，id 和修改（都只是用作测试以确保连接和打印正常工作）都很好，但我的问题出现在这里：

如果我们回到结构有这部分：

struct ElementText: Codable {
    let html: Bool
    let text: String
    let elementSet: ElementSet
    let element: Element

    enum CodingKeys: String, CodingKey {
        case html, text
        case elementSet = "element_set"
        case element
    }
}

它指的是示例 JSON 的以下部分：

"element_texts": [
      {
        "html": false,
        "text": "Woehler and Force Farm Equipment Building",
        "element_set": {
          "id": 1,
          "url": "http://www.ralstoncemetery.com/greeley/api/element_sets/1",
          "name": "Dublin Core",
          "resource": "element_sets"
        },
        "element": {
          "id": 50,
          "url": "http://www.ralstoncemetery.com/greeley/api/elements/50",
          "name": "Title",
          "resource": "elements"
        }
      },
      {
        "html": false,
        "text": "Woehler and Force Farm Equipment",
        "element_set": {
          "id": 1,
          "url": "http://www.ralstoncemetery.com/greeley/api/element_sets/1",
          "name": "Dublin Core",
          "resource": "element_sets"
        },
        "element": {
          "id": 39,
          "url": "http://www.ralstoncemetery.com/greeley/api/elements/39",
          "name": "Creator",
          "resource": "elements"
        }
      },
      {
        "html": false,
        "text": "Street view of the front exterior of Woehler and Force Farm Equipment. Several automobiles are visible through the windows of the store. The alley along the side of the building is also visible. There are several signs along the front of the building reading, 'Farm Equipment,' 'Kaiser Frazer W&F,' and 'Woehler & Force.'; Verso There is a sticker with typed black ink reading, 'Woehler & Force 1316-22 8th Ave. - Greeley, CO 1947. Orig. env. says Liberty Trucker Parts Co./ 690 Lincoln St./F.V. Altwater/POB 1889/Denver, Colo.'",
        "element_set": {
          "id": 3,
          "url": "http://www.ralstoncemetery.com/greeley/api/element_sets/3",
          "name": "Item Type Metadata",
          "resource": "element_sets"
        },
        "element": {
          "id": 54,
          "url": "http://www.ralstoncemetery.com/greeley/api/elements/54",
          "name": "Story",
          "resource": "elements"
        }
      }
    ],

**所以我的问题是：** 我将如何打印出第一个element_texts（为该text领域设置“Woehler and Force Farm Equipment Building”的那个）？

如果需要任何进一步的解释，我很乐意输入。或者，如果有人有任何资源用于这种级别的嵌套，我将非常感激。谢谢 -

标签： iosjsonswiftswift4

ios - Swift 4 - 将类结构的 JSON 响应嵌套到 TableViewCell 中

问题描述

解决方案

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