如何在 JSON 中循环数组 imageURL 以在图像视图中显示

Posted 2023-03-15

【中文标题】如何在 JSON 中循环数组 imageURL 以在图像视图中显示

【英文标题】：How to loop array imageURL in JSON for show in image view

【发布时间】：2016-09-03 07:43:42

【问题描述】：

我有用于循环数据（标题、价格、药物）JSON 的函数，但我无法循环 imageUrl 以在该函数的 imageview 中显示，请帮助查看我的代码。

这个函数barcodeReaded

func barcodeReaded(barcode: String) 
    print("Barcode is: \(barcode)")
    showCodeLabel.text = barcode

    let data = NSData(contentsOfURL: episode.thumbnailURL!)
    let image = UIImage(data: data!)
    self.thumbnailImageView.image = image

    let episodes = Episode.downloadAllEpisodes()
    var filteredEpisodes = episodes.filter( $0.testCode == barcode )
    if filteredEpisodes.count > 0 

        titleLabel.text = filteredEpisodes[0].title
        drugLabel.text = filteredEpisodes[0].drug
        priceLabel.text = filteredEpisodes[0].price
        //thumbnailImageView.image = filteredEpisodes[0].thumnailURL

        

这个 JSON 文件

    "episode": [

         
          "testCode": "11111111",
          "title": "Stomachic  mixture 180 ml",
          "drug": "AAAAA",
          "thumbnailURL": "https://firebasestorage.googleapis.com/v0/b/rxscan-a14ee.appspot.com/o/j01.jpg?alt=media&token=5718797b-fc9c-416e-9394-b544c2880dc9",
          "price": "100"
        ,
        
          "testCode": "22222222",
          "title": "Parasetamol   200 ml",
          "drug": "BBBBB",
          "thumbnailURL": "urlImage",
          "price": "150"
        ,
        
          "testCode": "33333333",
          "title": "Beramol 300 ml",
          "drug": "CCCCC",
          "thumbnailURL": "urlImage",
          "price": "120"
        

    ] 

这段代码

import Foundation

class Episode

    var title: String?
    var thumbnailURL: NSURL?
    var drug: String?
    var price: String?
    var testCode: String?

    init(title: String, thumbnailURL: NSURL, drug: String, price: String, testCode: String)

    self.title = title
    self.thumbnailURL = thumbnailURL
    self.drug = drug
    self.price = price
    self.testCode = testCode


typealias EpisodeDictionary = [String : AnyObject]

init(espDictionary: EpisodeDictionary)

    self.title = espDictionary["title"] as? String
    self.thumbnailURL = NSURL(string: espDictionary["thumbnailURL"] as! String)
    self.drug = espDictionary["drug"] as? String
    self.price = espDictionary["price"] as? String
    self.testCode = espDictionary["testCode"] as? String


static func downloadAllEpisodes() -> [Episode]

    var episodes = [Episode]()

    let jsonFile = NSBundle.mainBundle().pathForResource("testJson3edit6", ofType: "json")
    let jsonData = NSData(contentsOfFile: jsonFile!)
    if let jsonDictionary = NetworkService.parseJSONFromData(jsonData) 
        let espDictionaries = jsonDictionary["episodes"] as! [EpisodeDictionary]
        for dict in espDictionaries 
            let episode = Episode(espDictionary: dict)
            episodes.append(episode)
        
    

    return episodes
   
 

NetworkService.swift

import Foundation

class NetworkService

    // TODO: Make this class be able to download images from a URL
    lazy var configuration: NSURLSessionConfiguration = NSURLSessionConfiguration.defaultSessionConfiguration()
    lazy var session: NSURLSession = NSURLSession(configuration: self.configuration)

    let url: NSURL

    init(url: NSURL)
    
        self.url = url
    

    func downloadImage(completion: (NSData -> Void))
    
        let request = NSURLRequest(URL: self.url)
        let dataTask = session.dataTaskWithRequest(request)  (data, response, error) in

            if error == nil 
                if let httpResponse = response as? NSHTTPURLResponse 
                    switch (httpResponse.statusCode) 
                    case 200:
                        if let data = data 
                            completion(data)
                        

                    default:
                        print(httpResponse.statusCode)
                    
                
             else 
                print("Error download data: \(error?.localizedDescription)")
            
        

        dataTask.resume()
    


extension NetworkService

    static func parseJSONFromData(jsonData: NSData?) -> [String : AnyObject]?
    
        if let data = jsonData 
            do 
                let jsonDictionary = try NSJSONSerialization.JSONObjectWithData(data, options: .MutableContainers) as? [String : AnyObject]
                return jsonDictionary
             catch let error as NSError 
                print("Error processing json data: \(error.localizedDescription)")
            
        

        return nil
    

此代码用于获取在 detailViewController 中使用的图像，我不知道如何使用函数barcodeReaded。

if episode.thumbnailURL != nil 

            if let thumbnailURL = episode.thumbnailURL 
                let networkService = NetworkService(url: thumbnailURL)
                networkService.downloadImage( (data) in
            //thumbnailImageView.image = episode.thumbnailURL
            let image = UIImage(data: data)
            dispatch_async(dispatch_get_main_queue(), 
                self.thumbnailImageView.image = image
            )
        )
    

【参考方案1】：

基本上使用thumbnailImageView.image = episode.thumbnailURL，您正在尝试将String 分配给UIImage 类型的对象。

你应该这样做：

1.从您的 json 字符串中获取 NSURL

let url = NSURL(string: episode.thumbnailURL)!

2。获取NSData 的NSURL

let data = NSData(contentsOfURL: url)!

3.从NSData 分配UIImage

let image = UIImage(data: data)
self.thumbnailImageView.image = image

【讨论】：

对不起，我是初学者当我在函数barcodeReaded中添加代码时，出现错误无法将NSURL转换为第一行代码中的字符串。

@Kopiko in barcodeReaded 用此代码替换您的评论。

让 url = NSURL(string: episode.thumbnailURL)!这一行出错了。

@Kopiko 编译时间还是运行时间？

无法转换“NSURL”类型的值？到预期的参数类型“字符串”