我无法让我的委托协议工作。我使用这个堆栈溢出问题作为指南dispatch event to parent ViewController in swift。我不知道自从这篇文章以来Swift 3中的内容是否发生了变化，但我的parentViewController中的函数永远不会被调用。这是我的设置。
//PROTOCOL
protocol PDPPropDetailsDelegate {
func buttonPressed(PropDetailsVC: propertyDetailsVC)
}
//儿童视图控制器
class propertyDetailsVC: UIViewController {
var delegate: PDPPropDetailsDelegate?
@IBAction func emailButton(_ sender: AnyObject) {
self.delegate?.buttonPressed(PropDetailsVC: self)
}
}
在Child View Controller中调用Button。
//家长视图控制器
class ImageDetailsVC: UIViewController, PDPPropDetailsDelegate {
override func prepare(for segue: UIStoryboardSegue, sender: Any?) {
if segue.identifier == "container"{
container = segue.destination as! ContainerViewController
}
}
@IBAction func segmentControlAct(_ sender: Any) {
switch segmentControllerView.selectedIndex {
case 0: print("case 1")
container!.segueIdentifierReceivedFromParent("first")
case 1: print("case 2")
container!.segueIdentifierReceivedFromParent("second")
PropertyDetailsVC.delegate = self // **WHERE I SET DELEGATE**
setUpPropertyDetailsUI(property: filterImages)
default: print("default")
}
}
func buttonPressed(PropDetailsVC: propertyDetailsVC) {
print("BUTTON PRESSED")
}
}
永远不会调用按下按钮。我认为它与代理没有正确设置有关。不完全确定为什么会这样。我的setUpPropertyDetailsUI（属性：filterImages）从该VC获取Outlets并设置它可以正常工作。我做了一个断点，当我分割到PropertyDetailsVC时调用它。有什么建议或意见吗？
import UIKit
open class ContainerViewController: UIViewController {
//Manipulating container views
fileprivate weak var viewController : UIViewController!
//Keeping track of containerViews
fileprivate var containerViewObjects = Dictionary<String,UIViewController>()
/** Specifies which ever container view is on the front */
open var currentViewController : UIViewController{
get {
return self.viewController
}
}
fileprivate var segueIdentifier : String!
/*Identifier For First Container SubView*/
@IBInspectable internal var firstLinkedSubView : String!
override open func viewDidLoad() {
super.viewDidLoad()
}
open override func viewDidAppear(_ animated: Bool) {
if let identifier = firstLinkedSubView{
segueIdentifierReceivedFromParent(identifier)
}
}
override open func didReceiveMemoryWarning() {
super.didReceiveMemoryWarning()
// Dispose of any resources that can be recreated.
}
func segueIdentifierReceivedFromParent(_ identifier: String){
self.segueIdentifier = identifier
self.performSegue(withIdentifier: self.segueIdentifier, sender: nil)
}
override open func prepare(for segue: UIStoryboardSegue, sender: Any?) {
if segue.identifier == segueIdentifier{
//Remove Container View
if viewController != nil{
viewController.view.removeFromSuperview()
viewController = nil
}
//Add to dictionary if isn't already there
if ((self.containerViewObjects[self.segueIdentifier] == nil)){
viewController = segue.destination
self.containerViewObjects[self.segueIdentifier] = viewController
}else{
for (key, value) in self.containerViewObjects{
if key == self.segueIdentifier{
viewController = value
}
}
}
self.addChildViewController(viewController)
viewController.view.frame = CGRect(x: 0,y: 0, width: self.view.frame.width,height: self.view.frame.height)
self.view.addSubview(viewController.view)
viewController.didMove(toParentViewController: self)
}
}
}
import UIKit
class EmptySegue: UIStoryboardSegue{
override func perform() {
}
/*
// MARK: - Navigation
// In a storyboard-based application, you will often want to do a little preparation before navigation
override func prepareForSegue(segue: UIStoryboardSegue, sender: AnyObject?) {
// Get the new view controller using segue.destinationViewController.
// Pass the selected object to the new view controller.
}
*/
}
答案 0 :(得分：1)
你似乎对应用程序的流程感到有些困惑。以下是我为其他人写的关于同一主题的问题的答案：
https://stackoverflow.com/a/45312362/3832646
你的协议和子视图控制器看起来很棒，但是这里的其余代码有很多不妥之处：
您的prepare(for segue:_, sender:_)通常是您为目标（子）视图控制器设置委托的位置。
PropertyDetailsVC.delegate = self无法做任何事情 - 您需要一个视图控制器实例来设置其委托。
看起来您正在使用某种容器全局变量，我不确定它的用途。
看一下我发布的答案并再次开始。它在Swift 3中。