Question

我目前有两个简单的类，一个是容器视图控制器，另一个是子视图控制器。我在ContainerViewController.swift文件中有一个动作，但需要在HomeViewController.swift文件中调用它。我显然不能只拨打ContainerViewController.presentDetailController(self)，所以我该如何处理？

ContainerViewController.swift

import UIKit

class ContainerViewController: UIViewController {

    var currentDetailViewController: UIViewController?

    override init() {
        super.init()
    }

    required init(coder aDecoder: NSCoder) {
        super.init(coder: aDecoder)
    }

    convenience init(viewController: UIViewController) {
        self.init()

        currentDetailViewController = viewController
        self.presentDetailController(viewController)
    }

    override func viewDidLoad() {
        super.viewDidLoad()

        var homeViewController: HomeViewController = HomeViewController.alloc()
        self.presentDetailController(homeViewController)
    }

    override func didReceiveMemoryWarning() { super.didReceiveMemoryWarning() }

    func presentDetailController(detailViewController: UIViewController) {
        if((self.currentDetailViewController) != nil) {
            self.removeCurrentDetailViewController();
        }

        self.addChildViewController(detailViewController)

        detailViewController.view.frame = self.frameForDetailController()

        self.view.addSubview(detailViewController.view)
        self.currentDetailViewController = detailViewController

        detailViewController.didMoveToParentViewController(self)
    }

    func removeCurrentDetailViewController() {
        self.currentDetailViewController?.willMoveToParentViewController(nil)
        self.currentDetailViewController?.view.removeFromSuperview()
        self.currentDetailViewController?.removeFromParentViewController()
    }

    func frameForDetailController() -> CGRect {
        var detailFrame: CGRect = self.view.bounds

        return detailFrame
    }

}

HomeViewController.swift

import UIKit

class HomeViewController: UIViewController {

    func initView () {
        self.view.backgroundColor = UIColor.redColor()
        var button: UIButton = UIButton(frame: CGRectMake(20, 20, 50, 50))
        button.backgroundColor = UIColor.greenColor()
        button.addTarget(self, action: Selector("ContainerViewController.presentDetailController(self)"), forControlEvents: UIControlEvents.TouchDown) // This results in a fatal error!
        self.view.addSubview(button)
    }

    override func viewDidLoad() {
        super.viewDidLoad()
        initView();
    }
}

Answer 1

我认为我们只能通过使用委托将消息传递回父视图控制器。可能还有其他方式，但这是唯一优雅的方式。

方法 - 1

1）

在父视图控制器中创建协议并实现

@interface ParentController : UIViewController <NaviagationDelegate>

@implementation ParentController
//implement method here
//{
// your action in parent controller
//}

2）

现在使用NaviagationDelegate

在子控制器中创建属性

@property (nonatomic, weak) id <NaviagationDelegate> navigationDelegate;

在子控制器的事件操作上调用委托方法

    //Button action method
    {
        [self.navigationDelegate setText:@"action"];
    }

3）在父视图控制器中将子控制器的委托属性初始化为self

prepareForSegue:(UIStoryboardSegue *)segue sender:(id)sender
{
    if([segue.destinationViewController isKindOfClass:[ChildContoller class]])
    {
        [segue.destinationViewController setNavigationDelegate:self];
    }
}

方法 - 2

通过检查从self.navigationController.viewControllers到parentController类的所有控制器来获取父控制器的引用。

如何以编程方式链接此按钮和此操作？

1 个答案: