尝试将数据从一个视图控制器（从alamofire请求）发送到导航控制器中的下一个视图控制器。
我和一位代表试图这样做，但我没有让它发挥作用。我已经知道这不是方法，但我需要找到一个解决方案让它工作。
从发送变量标题的视图控制器中查看代码：
protocol SendDataToScanInfo {
func sendData (vendorname01 : String, productname01: String, productstatus01: String, productdescription01: String)
}
class ScanController: UIViewController, AVCaptureMetadataOutputObjectsDelegate, CLLocationManagerDelegate{
var delegate:SendDataToScanInfo?
func captureOutput(_ captureOutput: AVCaptureOutput!, didOutputMetadataObjects metadataObjects: [Any]!, from connection: AVCaptureConnection!) {
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
let productname0:JSON = json["productname"]
let productnameString = productname0.string
let tagstate0:JSON = json["tagstate"]
let tagstateString = tagstate0.string
let vendorname0:JSON = json["vendorname"]
let vendornameString = vendorname0.string
//self.performSegue(withIdentifier: "ScanInfo", sender: productdescString)
self.delegate?.sendData(vendorname01: vendornameString!, productname01: productnameString!, productstatus01: tagstateString!, productdescription01: productdescString!)
print(vendornameString)
}
if code != nil
{
let mainStoryboard = UIStoryboard(name: "Main", bundle: nil)
let destination = mainStoryboard.instantiateViewController(withIdentifier: "ScanInfo")
navigationController?.pushViewController(destination, animated: true)
}
captureSession.stopRunning();
//self.dismiss(animated: true, completion: nil)
}
}
}
下一个Viewcontroller应该收到它：
class ScanInfoViewController: UIViewController, SendDataToScanInfo {
@IBOutlet weak var Vendor: UILabel!
@IBOutlet weak var VendorScan: UILabel!
@IBOutlet weak var Product: UILabel!
@IBOutlet weak var ProductScan: UILabel!
@IBOutlet weak var Status: UILabel!
@IBOutlet weak var DescriptionScan: UILabel!
@IBOutlet weak var Description: UILabel!
@IBOutlet weak var StatusScan: UILabel!
override func viewDidLoad() {
super.viewDidLoad()
DescriptionScan.text = descriptionBLA
print("jddjd", descriptionBLA)
let URL_SCAN_INFO = "http://makeitrain.get-legit.com:8998/checktag"
// Do any additional setup after loading the view.
}
override func didReceiveMemoryWarning() {
super.didReceiveMemoryWarning()
// Dispose of any resources that can be recreated.
}
func sendData(vendorname01: String, productname01: String, productstatus01: String, productdescription01: String) {
VendorScan.text = vendorname01
ProductScan.text = productname01
DescriptionScan.text = productdescription01
StatusScan.text = productstatus01
print("MMMM", StatusScan.text)
}
override func prepare(for segue: UIStoryboardSegue, sender: Any?) {
if segue.identifier == "ScanInfo" {
let sendingVC: ScanController = segue.destination as! ScanController
sendingVC.delegate = self
}
}
}
我希望有人可以帮助我！
答案 0 :(得分：0)
为了传递数据，就像williej926所说，segues是要走的路。要将数据从一个视图控制器传递到另一个视图控制器，您需要在这两个视图控制器之间创建一个segue，如果项目中有多个用于传递数据的segue，则为segue提供一个标识符，这是必须的。在第一个视图控制器的类中，您应该使用内置的方法创建prepareForSegue方法。在prepareForSegue方法中，如果segue的标识符等于您在故事板中设置的标识符，则可以编写。在那个if语句中，你需要告诉这个viewcontroller你的segue的目的地是什么。为此，请编写let destination = segue.destination as! nextViewControllerClass.要访问变量并在第二个viewcontroller中设置它们，请编写destination.variableName = thisVariableName。这是一个示例，向您展示纯粹代码中的内容。
在First View Controller的类中
class FirstViewController: UIViewController {
var thisString: String?
override func prepare(for segue: UIStoryboardSegue, sender: Any?) {
if let identifier = segue.identifier {
if(identifier == "secondViewController") {
let destination = segue.destination as! SecondViewController//SecondViewController is second view controller's class
destination.myString = thisString
}
}
}
}
第二个视图控制器的类
class SecondViewController: UIViewController {
var myString: String?//this will equal to thisString in FirstViewController
}
答案 1 :(得分：0)
我wrote an answer关于这个不久前：
将信息从一个VC传递到另一个VC的简单方法是通过initiliazer，或者通过在呈现第二个VC之前设置的变量。
secone方法会让你通过一个委托，主要是在将数据传递给初始VC时。无论哪种方式，您都需要类似于此的设置：
class LoggedInVCViewController : UIViewController {
var info : String? {
didSet {
if let newInfo = self.info {
//do what ever you need to do here
}
}
}
override viewDidLoad() {
super.viewDidLoad()
}
}
func presentLoggedInScreen(yourInfo: String) {
let stroyboard:UIStoryboard = UIStoryboard(name: "Main", bundle: nil)
let loggedInVC:LoggedInVCViewController =
storyboard.instantiateViewController(withIdentifier: "loggedInVC") as!
LoggedInVCViewController
loggedInVC.info = yourInfo
self.present(loggedInVC, animated: true, completion: nil)
}
class LoggedInVCViewController : UIViewController {
var info : Any? {
get {
if let this = self.info {
return this
} else {
return nil
}
} set {
if let new = newValue {
//
}
}
}
init(info: Any?) {
//This first line is key, it also calls viewDidLoad() internally, so don't re-write viewDidLoad() here!!
super.init(nibName: nil, bundle: nil)
if let newInfo = info {
//here we check info for whatever you pass to it
self.info = newInfo
}
}
override func viewDidLoad() {
super.viewDidLoad()
}
required init?(coder aDecoder: NSCoder) {
fatalError("init(coder:) has not been implemented")
}
}
然后使用：
func presentLoggedInScreen(yourInfo: String) {
let loggedInVC = LoggedInVCViewController(info: yourInfo)
self.present(loggedInVC, animated: true, completion: nil)
}
或者，如果您正在使用变量方法：
func presentLoggedInScreen(yourInfo: String) {
let loggedInVC = LoggedInVCViewController()
loggedInVC.info = yourInfo
self.present(loggedInVC, animated: true, completion: nil)
}
我也会过去，并链接到其他帖子，其中讨论使用Storyboard的注意事项，以及传递数据的自定义初始化程序。我也读过它们了！
答案 2 :(得分：-1)
最好的方法是使用segue。在控制器之间连接一个segue，在prepareForSegue中添加一个代表您正在调整的控制器的变量，如下所示：let viewController = segue.destination as! viewController。现在，您可以使用viewController访问和更改viewController.variable内的变量。