快速从 json 文件加载 NSURL 并将其链接到 imageView

Question

好的，所以我试图从 json 文件中获取一个“路径”，它是一个 url，并将其链接到我项目中的 imageView。图像和路径像这样放在一个 json 行中

{image:"http//www.something.com", path:"http://www.godbsdahb.com" }

我设法下载并用图像填充了滚动视图，但现在我想单击图像然后重定向到另一个 url。我管理重定向，但不管理图像路径的链接。我迷失在如何做到这一点。任何帮助将不胜感激。 这是我到目前为止所拥有的，它也可以工作，但没有指向路径和图像的链接。

感谢您对此的任何帮助：

这是它的代码：

    var numOfPromo = 0;

override func didReceiveMemoryWarning() {
    super.didReceiveMemoryWarning()
    // Dispose of any resources that can be recreated.
}

private func loadPromo() {
    numOfPromo = 0;
    PromoMan.sharedInstance.getAllPromoFromServer({
        promotions in
        for (_,promotion) in promotions {
            self.downloadImage(NSURL(string: promotion.picture)!)
            //The path for the promo is promotion.path
        }},
        onFail: { error_code, detail in Utility.log(self.dynamicType, msg: "Get All Promotions Fail, error_code: \(error_code), detail: \(detail)",
            function: "viewDidLoad")})
}

//Add paths to the promtion images
func imageTapped(gesture: UIGestureRecognizer)
{
    let url = NSURL(string: "http://google.com/")
    UIApplication.sharedApplication().openURL(url!)
}

func downloadImage(url: NSURL){
    getDataFromUrl(url) { (data, response, error)  in
        dispatch_async(dispatch_get_main_queue()) { () -> Void in
            guard let data = data where error == nil else { return }

            let tapGesture = UITapGestureRecognizer(target: self, action: #selector(PromotionViewController.imageTapped))
            let imageView = UIImageView(image: UIImage(data: data));
            imageView.addGestureRecognizer(tapGesture)
            imageView.userInteractionEnabled = true

            imageView.frame = CGRect(x: 0,
                y: Int(self.numOfPromo * 230), width: Int(self.pScrollView.frame.size.width), height: 200)
            self.pScrollView.addSubview(imageView)
            self.numOfPromo = self.numOfPromo + 1;

            //Make sure the images will all fit into the scrollview

            self.pScrollView.contentSize = CGSizeMake(self.pScrollView.frame.size.width,
                CGFloat(self.numOfPromo * 230));
        }
    }
}

func getDataFromUrl(url:NSURL, completion: ((data: NSData?, response: NSURLResponse?, error: NSError? ) -> Void)) {
    NSURLSession.sharedSession().dataTaskWithURL(url) { (data, response, error) in
        completion(data: data, response: response, error: error)
        }.resume()
}

更新：

这是图像和数据的 http 调用

 public func getAllPromotionsFromServer(
    onSuccess: (promotions: [String: Promotion])->(),
    onFail: (error_code: APIErrorCode, detail: String)->()){

        let url = Config.getBaseUrl() + "/promotions"

        Utility.log(self.dynamicType, msg: "Get All Promotions from Server", function: "getAllPromotionsFromServer")

        APIManager.sharedInstance.get(url,params: nil,completion: { response in
            //Change back to global queue
            dispatch_async(dispatch_get_global_queue(QOS_CLASS_BACKGROUND, 0), {
                switch response {

                case APIResult.Failure(let error):

                    let msg = "Get Promotions Fail"
                    Utility.log(self.dynamicType, msg: msg, function: "getAllPromotionsFromServer")

                    let code = Utility.getAPIErrorCode(error)
                    onFail(error_code: code.error_code, detail: code.detail)
                    return

                case APIResult.Success(let response):

                    if response.HTTP_Status == 200
                    {
                        let promotions = APIJSONParser.parsePromotions(response.jsonData)
                        print("Json response")
                        print(response.jsonData)
                        Utility.log(self.dynamicType, msg: "Get Promotions Success: no. \(promotions.count)", function: "getAllPromotionsFromServer")
                        onSuccess(promotions: promotions)
                        return

                    }
                    else{
                        let code = Utility.getAPIErrorCode(response)
                        onFail(error_code: code.error_code, detail: code.detail)
                        return
                    }

                }
            })
        })

}

}

更新：

新代码块

 private func loadPromotions() {
    numberPromotions = 0;
    PromotionManager.sharedInstance.getAllPromotionsFromServer({
        promotions in
        for (_,promotion) in promotions {
            Utility.log(self.dynamicType, msg: promotion.picture, function: "viewDidLoad")

            let p = (picture: promotion.picture, path: promotion.path)
            self.promos.append(p)
            self.downloadImage(NSURL(string: promotion.picture)!, index: self.promos.count)
            //The path for the promo is promotion.path
        }},
        onFail: { error_code, detail in Utility.log(self.dynamicType, msg: "Get All Promotions Fail, error_code: \(error_code), detail: \(detail)",
            function: "viewDidLoad")})
}

//Add paths to the promtion images
func imageTapped(gesture: UITapGestureRecognizer)
{
            //let url = NSURL(string: "http://google.com/")
            //UIApplication.sharedApplication().openURL(url!)
    if let imageView = gesture as? UIImageView
    {
        if let url = NSURL(string: self.promos[imageView.tag].path)
        {
            UIApplication.sharedApplication().openURL(url)
        }
    }


}

func downloadImage(url: NSURL, index : Int){
    getDataFromUrl(url) { (data, response, error)  in
        dispatch_async(dispatch_get_main_queue()) { () -> Void in
            guard let data = data where error == nil else { return }

            let tapGesture = UITapGestureRecognizer(target: self, action: #selector(PromotionViewController.imageTapped))
            let imageView = UIImageView(image: UIImage(data: data));
            imageView.addGestureRecognizer(tapGesture)
            imageView.userInteractionEnabled = true
            imageView.tag = index
            //get images with a space between them 
            //200 = no space
            //230 = black space
            imageView.frame = CGRect(x: 0,
                y: Int(self.numberPromotions * 230), width: Int(self.promotionsScrollView.frame.size.width), height: 200)
            self.promotionsScrollView.addSubview(imageView)
            self.numberPromotions = self.numberPromotions + 1;

            //Make sure the images will all fit into the scrollview

            self.promotionsScrollView.contentSize = CGSizeMake(self.promotionsScrollView.frame.size.width,
                CGFloat(self.numberPromotions * 230));
        }
    }
}

Answer 1

当您获得promotions 对象（解析后的 JSON 数据）时，您就有了图片和路径。

您已经在使用图片在滚动视图中显示图片。

现在您需要做的是告诉手势识别器转到属于该图像的特定路径。由于您对所有图像都有一个手势识别器（这是完美的），因此您需要“以某种方式”将图片与路径相关联。

为此，您可以在类的范围内创建一个变量，例如字典，您将在其中保存所有促销及其图片和路径。

我将使用元组数组，但您可以使用任何您想要的数据类型（字典、数组等）。

private var promos = Array<(picture: String, path: String)>()

在你的for循环中，将数据保存到刚刚创建的变量中：

for (_, promotion) in promotions {
    let p = (picture: promotion.picture, path: promotion.path)
    self.promos.append(p)
    self.downloadImage(NSURL(string: promotion.picture)!, index: self.promos.count - 1)
}

现在你需要告诉每个UIImageView它所属的promos数组的索引，就在将它添加到滚动视图之前（可能是在设置userInteractionEnabled之后：

imageView.tag = index

您需要将index 添加为函数的参数：

func downloadImage(url: NSURL, index: Int) { ... }

现在您可以从手势识别器操作中访问它：

func imageTapped(gesture: UIGestureRecognizer)
{
    if let imageView = gesture.view as? UIImageView {
        if let url = NSURL(string: self.promos[imageView.tag].path) {
            UIApplication.sharedApplication().openURL(url)
        }
    }
}

我建议将gesture 更改为sender，因为这样更有意义。