Swift - 如何從特定實例調用方法？

Question

我目前正在開發一個iOS應用程序，使用CarbonKit庫進行導航。我目前在第一個選項卡中有一個UITableView，我希望在選擇單元格時以編程方式導航到另一個選項卡。

我已實現了以下功能下我主CarbonKit視圖控制器：

import CarbonKit 

class ViewController: UIViewController, CarbonTabSwipeNavigationDelegate { 


    func carbonTabSwipeNavigation(carbonTabSwipeNavigation: CarbonTabSwipeNavigation, viewControllerAtIndex index: UInt) -> UIViewController  { 

     switch index { 
     case 0: 
      return self.storyboard!.instantiateViewControllerWithIdentifier("AircraftViewController") as! AircraftViewController 
     case 1: 
      return self.storyboard!.instantiateViewControllerWithIdentifier("LoadController") as! LoadController 
     case 3: 
      return self.storyboard!.instantiateViewControllerWithIdentifier("SettingsController") as! SettingsController 
     default: 
      return self.storyboard!.instantiateViewControllerWithIdentifier("ViewControllerOne") as! ViewControllerOne 
     } 
    } 

    func navigate(index: UInt) { 
     carbonTabSwipeNavigation.setCurrentTabIndex(index, withAnimation: true) 
    } 

} 

setCurrentTabIndex是由庫以編程切換標籤提供的功能。

在我UITableViewController我有以下幾點：

import UIKit 
import CarbonKit 

class SecondViewController: UITableViewController { 

    override func tableView(tableView: UITableView, didSelectRowAtIndexPath indexPath: NSIndexPath) { 

     \\ First Attempt 
     (ViewController() as CarbonTabSwipeNavigationDelegate).navigate(2) 

     \\ Second Attempt 
     let viewController = self.storyboard?.instantiateViewControllerWithIdentifier("controller") as! ViewController 
     viewController.navigate(2) 
    } 

} 

據我所知，我的第一次嘗試，我創建的ViewController一個新實例，我的第二次嘗試沒有選擇我所期待的實例。

如何從SecondViewController開始在ViewController的第一個實例中最好地激活該方法？

Answer 1

開始加入了CarbonTabSwipeNavigation屬性您SecondViewController類，所以你將有你的導航提供接入：

import UIKit 
import CarbonKit 

class SecondViewController: UITableViewController { 
    weak var carbonNavigation : CarbonTabSwipeNavigation?; 

    override func tableView(tableView: UITableView, didSelectRowAtIndexPath indexPath: NSIndexPath) { 
     if let carbonNav = self.carbonNavigation { 
      carbonNav.setCurrentTabIndex(index, withAnimation: true) 
     } 
    } 

} 

接下來，我們需要設置carbonNavigation屬性，所以這將是可供使用。它看起來像你的CarbonTabSwipeNavigationDelegate是一個很好的去處。在附註中，我沒有看到您的代表已經返回SecondViewController - 是否有意？

import CarbonKit 

class ViewController: UIViewController, CarbonTabSwipeNavigationDelegate { 


    func carbonTabSwipeNavigation(carbonTabSwipeNavigation: CarbonTabSwipeNavigation, viewControllerAtIndex index: UInt) -> UIViewController  { 

     switch index { 
     case 0: 
      let aircraftVC = self.storyboard!.instantiateViewControllerWithIdentifier("AircraftViewController") as! AircraftViewController 
      aircraftVC.carbonNavigation = carbonTabSwipeNavigation 
      return aircraftVC 
     case 1: 
      // do something similar, instantiate view controller, set navigation property 
      return self.storyboard!.instantiateViewControllerWithIdentifier("LoadController") as! LoadController 
     case 3: 
      // do something similar, instantiate view controller, set navigation property 
      return self.storyboard!.instantiateViewControllerWithIdentifier("SettingsController") as! SettingsController 
     default: 
      // do something similar, instantiate view controller, set navigation property 
      return self.storyboard!.instantiateViewControllerWithIdentifier("ViewControllerOne") as! ViewControllerOne 
     } 
    } 

    func navigate(index: UInt) { 
     carbonTabSwipeNavigation.setCurrentTabIndex(index, withAnimation: true) 
    } 
} 

你也可以添加一個ViewController屬性，而不是一個CarbonTabSwipeNavigation，揭露所有從碳需要按照ViewController方法的方法。這意味着更改財產聲明的類型並將其設置爲self而不是carbonTabSwipeNavigation。