Swift 集合视图总是 return 来自模型的第一个默认值

Question

我有一个包含 struct 和 array 的模型。 Form Hit struct ，我想像这样 tagLabel.text = photoviewModel?.hits.tags 访问标签属性，这样我就可以将属性的值显示到标签中。 例如，当我单击第一个集合视图单元格时，它应该 return 图像和标签正确，但问题是我得到了正确的图像，但总是 return 相同的标签值。 截图添加到下面..

这是模型。

import Foundation

struct Photo: Codable {
    let total, totalHits: Int
    let hits: [Hit]
}

struct Hit: Codable {
    let id: Int
    let pageURL: String
    let type, tags: String
    let previewURL: String
    let previewWidth, previewHeight: Int
    let webformatURL: String
    let webformatWidth, webformatHeight: Int
    let largeImageURL: String
    let imageWidth, imageHeight, imageSize, views: Int
    let downloads, collections, likes, comments: Int
    let userID: Int
    let user: String
    let userImageURL: String

    enum CodingKeys: String, CodingKey {
        case id, pageURL, type, tags, previewURL, previewWidth, previewHeight, webformatURL, webformatWidth, webformatHeight, largeImageURL, imageWidth, imageHeight, imageSize, views, downloads, collections, likes, comments
        case userID = "user_id"
        case user, userImageURL
    }
}

这是视图模型。

import Foundation

class PhotoViewModel {
    
    
   private let networkManager: NetworkManagerProtocol
    
   
    var  hits = [Hit]()
    private var cache = [String: Data]()
   // var net  = NetworkManager()
     weak var delegate: PhotoViewable?
    
    
    init(networkManager: NetworkManagerProtocol) {
        self.networkManager = networkManager
       
    }
    
    var rows: Int {
        return hits.count
    }
    
    func fecthPhotoRecord(){
        
        let networkUrl = NetworkURLs.baseURL
        networkManager.getModel(Photo.self, from: networkUrl) { [weak self] result in
            switch result{
            case.success(let photo):
                self?.hits = photo.hits
                self?.delegate?.refreshUI()
            case.failure(let error):
                print(error)
               self?.delegate?.showError()
            }
        
        }
    }
    func downloadImage(row: Int, completion: @escaping (Data) -> Void) {
        
        let hit = hits[row]
        let hitpath = hit.previewURL
        
        if let data = cache[hitpath] {
            completion(data)
            return
        }
        
        networkManager
            .getData(from: hitpath) { result in
                switch result {
                case .success(let data):
                    self.cache[hitpath] = data
                    DispatchQueue.main.async {
                        completion(data)
                    }
                case .failure(let error):
                    print(error)
                }
            }
    }

这是视图控制器中的代码。

import UIKit

class PhtotoDetailsViewController: UIViewController {


    var photoviewModel : PhotoViewModel?
    var peopleDetailsViewModel:PeopleDetailsViewModel?
    
    private var stackView: UIStackView = {
            let stackView = UIStackView()
            stackView.axis = .vertical
            stackView.distribution = .fill
            stackView.alignment = .fill
            stackView.spacing = 5
            stackView.translatesAutoresizingMaskIntoConstraints = false
            return stackView
        }()
    private let imageView: UIImageView = {
        let imageView = UIImageView(frame: .zero)
        imageView.contentMode = .scaleAspectFill
        
        imageView.translatesAutoresizingMaskIntoConstraints = false
        return imageView
    }()

   private let tagLabel: UILabel = {
        let label = UILabel(frame: .zero)
        label.textAlignment = .center
        label.numberOfLines = 0
       label.translatesAutoresizingMaskIntoConstraints = false
        return label
    }()
    
    override func viewDidLoad() {
        super.viewDidLoad()
        view.backgroundColor = .white
        view.addSubview(stackView)
        view.addSubview(tagLabel)
        view.addSubview(imageView)
        setUpUI()
        setPhoto()
        setContrain()
      
    }
    
    private func setContrain(){
        
        
        NSLayoutConstraint.activate([
            
            stackView.topAnchor.constraint(equalTo: view.topAnchor,constant: 100),
            stackView.bottomAnchor.constraint(equalTo: view.bottomAnchor,constant: -200),
            stackView.leftAnchor.constraint(equalTo: view.leftAnchor , constant: 10),
            stackView.rightAnchor.constraint(equalTo: view.rightAnchor,constant: 10),
            stackView.leadingAnchor.constraint(equalTo: view.leadingAnchor),
            stackView.trailingAnchor.constraint(equalTo: view.trailingAnchor )
           
        ])
        
        stackView.addArrangedSubview(imageView)
        stackView.addArrangedSubview(tagLabel)
       
    }
    private func setUpUI(){
        tagLabel.text = photoviewModel?.hits.first?.tags
        
    }
    
    var rowSelected = 0
     
     private func setPhoto(){
         
         photoviewModel?.downloadImage(row: rowSelected) { [weak self] data in
                     DispatchQueue.main.async {
                         let image = UIImage(data: data)
                         self?.imageView.image = image
                     }
         }
         
     }
}

我在这条线上有问题..

private func setUpUI(){
            tagLabel.text = photoviewModel?.hits.first?.tags
            
        }

这是应用首次加载时的屏幕截图，它有图像和标签属性 ...

当我单击第三个单元格表单集合时它具有正确的图像但正确的标签属性。

Answer 1

在你的 setupUI() 中用这个

替换行 tagLabel.text = photoviewModel?.hits.first?.tags

tagLabel.text = photoviewModel?.hits[rowSelected].tags

Swift 集合视图总是 return 来自模型的第一个默认值

Swift Collection View always return first default value from Model

model

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uicollectionview

uicollectionviewcell

swift