swift 3 : Need to pass data to next view controller without moving to it

Question

我需要传递来自一个 View Controller 的数据、来自 Alamofire 请求的数据，并且必须发送到下一个 View Controller 中的 UIlabels。我还不想转换到该 View Controller 。但目标 View Controller 必须能够读取和使用 Alamofire 请求中的数据。我用 segue 尝试了它，但我没有让它工作，我怀疑这是否是正确的方法。

这就是我所拥有的:

Alamofire.request(URL_SCAN_ID, method: .post, parameters: ScanParameters, encoding: JSONEncoding.default) .responseJSON
                {

                    response in

                    //printing response
                    print(response.request!)
                    print(response.response!)
                    print(response.data!)
                    print(response.result)
                    print(response.error)

                    //getting the json value from the server
                    let value = response.result.value
                    print(value!)
                    let json = JSON(value!)

                    let productdesc0:JSON = json["productdesc"]
                    let productdescString = productdesc0.string



                    self.performSegue(withIdentifier: "ScanInfo", sender: productdescString)


                   func prepareForSegue(segue: UIStoryboardSegue, sender: Any){
                    if (segue.identifier == "ScanInfo"){
                        let destinationVC = segue.destination as! ScanInfoViewController
                        destinationVC.productdescription01 = productdescString!
                        print("oeiii",sender)
                    }


            }

我认为数据甚至没有发送到segue...打印没有显示任何内容。

Answer 1

在您的代码中，准备函数位于闭包内。它必须在文件级别。如果给定的代码来自 View Controller ，则它必须类似于 -

override func prepare(for segue: UIStoryboardSegue, sender: Any?) {
    if (segue.identifier == "ScanInfo"){
        let destinationVC = segue.destination as! ScanInfoViewController
        destinationVC.productdescription01 = productdescString!
        print("oeiii",sender)
    }
}