动态分配要导航的视图控制器

Question

就我而言，我有UITableView并具有">查看全部">按钮，用于在单独的屏幕中列出所有项目。所以我在cellForRowAt中为UIButton动作方法添加了目标。现在我在行动方法中所做的：

@IBAction func btnViewAllOffer(_ sender: UIButton) {
let buttonPosition = sender.convert(CGPoint.zero, to: self.tblOfferView)
let indexPath = self.tblOfferView.indexPathForRow(at: buttonPosition)
if indexPath != nil {
if let type = self.homeData[indexPath!.section].type {
if type == HomeDataType.SponserProduct.rawValue {
let vc1 = self.storyboard?.instantiateViewController(withIdentifier: "ViewController1") as! ViewController1
if let title = self.homeData[indexPath!.section].title {
vc1.title = title
}
self.navigationController?.pushViewController(vc1, animated: true)
} else if type == HomeDataType.Offer.rawValue {
let vc2 = self.storyboard?.instantiateViewController(withIdentifier: "ViewController2") as! ViewController2
if let title = self.homeData[indexPath!.section].title {
vc2.title = title
}
self.navigationController?.pushViewController(vc2, animated: true)
} else if type == HomeDataType.BestSeller.rawValue {
let vc3 = self.storyboard?.instantiateViewController(withIdentifier: "ViewController3") as! ViewController3
if let title = self.homeData[indexPath!.section].title {
vc3.title = title
}
self.navigationController?.pushViewController(vc3, animated: true)
}
}
}
}

我需要的是，有什么方法可以最小化代码并动态分配视图控制器，这样就不需要实例化每个视图控制器并每次都推送它们？ 像这样：

var vc = UIViewController()
if let type = self.homeData[indexPath!.section].type {
if type == HomeDataType.SponserProduct.rawValue {
vc = ViewController1()
}
else if type == HomeDataType.Offer.rawValue {
vc = ViewController2()
} else if type == HomeDataType.BestSeller.rawValue {
vc = ViewController3()
}
}
self.navigationController?.pushViewController(vc, animated: true)

Answer 1

使用protocol(SimilarViewController(来定义公共属性，如title：

protocol SimilarViewController {
var title: String? { get set }
}
class ViewController1: UIViewController, SimilarViewController {
var title: String?
}
class ViewController2: UIViewController, SimilarViewController {
var title: String?
}
class ViewController3: UIViewController, SimilarViewController {
var title: String?
}

@IBAction func btnViewAllOffer(_ sender: UIButton) {
let buttonPosition = sender.convert(CGPoint.zero, to: self.tblOfferView)
let indexPath = self.tblOfferView.indexPathForRow(at: buttonPosition)
if indexPath != nil {
if let type = self.homeData[indexPath!.section].type {
var vcGeneric: SimilarViewController?
if type == HomeDataType.SponserProduct.rawValue {
vcGeneric = self.storyboard?.instantiateViewController(withIdentifier: "ViewController1") as! ViewController1
} else if type == HomeDataType.Offer.rawValue {
vcGeneric = self.storyboard?.instantiateViewController(withIdentifier: "ViewController2") as! ViewController2
} else if type == HomeDataType.BestSeller.rawValue {
vcGeneric = self.storyboard?.instantiateViewController(withIdentifier: "ViewController3") as! ViewController3
}

if let title = self.homeData[indexPath!.section].title {
vcGeneric?.title = title
}
if let vcGeneric = vcGeneric  as? UIViewController {
self.navigationController?.pushViewController(vcGeneric, animated: true)
}
}
}
}

Answer 2

1：创建一个结构并为其赋值。

struct TitleDetails { 
static var title : String = ""
}

2：创建视图控制器的扩展并使用它来避免代码重复。

extension UIViewController {
func pushVC(_ vcName : String) {
let vc = UIStoryboard.init(name: "Main", bundle: Bundle.main).instantiateViewController(withIdentifier: vcname)
self.navigationController?.pushViewController(vc, animated: true)
}
}

3：现在你可以直接称之为，

TitleDetails.title = yourTitleValue
self.pushVC("ViewController1")

在目标视图控制器的 ViewDidLoad(( 方法中，

self.title = TitleDetails.title

Answer 3

创建 BaseViewController并从 BaseViewController 派生其他 ViewController

class BaseViewController: UIViewController {
var viewTitle = ""
override func viewDidLoad() {
super.viewDidLoad()
// Do any additional setup after loading the view.
}
func pushVC(_ vcName : String) {
let vc = UIStoryboard.init(name: "Main", bundle: Bundle.main).instantiateViewController(withIdentifier: vcName)
self.navigationController?.pushViewController(vc, animated: true)
}
}

并在您需要的视图控制器上使用以下代码，例如：

@IBAction func btnViewAllOffer(_ sender: UIButton) {
let buttonPosition = sender.convert(CGPoint.zero, to: self.tblOfferView)
let indexPath = self.tblOfferView.indexPathForRow(at: buttonPosition)
if indexPath != nil {
if let type = self.homeData[indexPath!.section].type {
self.viewTitle = self.homeData[indexPath!.section].title
if type == HomeDataType.SponserProduct.rawValue {
self.pushVC("ViewController1")
} else if type == HomeDataType.Offer.rawValue {
self.pushVC("ViewController2")
} else if type == HomeDataType.BestSeller.rawValue {
self.pushVC("ViewController3")
}
}
}
}