NSUserDefaults的使用節省的ViewController頁觸動按鈕塞格斯到導航控制器

Question

所以我有一個視圖控制器是應用程序的初始視圖控制器4個按鈕。

每個按鈕是「SHOW」 segued到不同的導航控制器（其連接到一個UITableView）。

我的目標就是以某種方式保存哪個按鈕被觸動NSUserDefaults的使用和跳過視圖控制器和應用程序被打開，每次直接到選定的導航控制器！這可能嗎？

我在斯威夫特

寫這本是我的AppDelegate（上警告 「變種buttonSelected」）：

import UIKit 

@UIApplicationMain 
class AppDelegate: UIResponder, UIApplicationDelegate { 

    var window: UIWindow? 

    func application(application: UIApplication, didFinishLaunchingWithOptions launchOptions: [NSObject: AnyObject]?) -> Bool { 

     var buttonSelected = NSUserDefaults.standardUserDefaults().integerForKey("buttonSelected") 

     print("run") 

     return true 
    } 
} 

這是我的視圖控制器爲我的4個按鍵：

import UIKit 

class NSUserDefault: UIViewController { 

    override func prepareForSegue(segue: UIStoryboardSegue, sender: AnyObject!) { 

     var buttonSelected: Int = 0 

     if (segue.identifier == "button1Segue") { 

      buttonSelected = 1 
     } 

     else if (segue.identifier == "button2Segue") { 

      buttonSelected = 2 
     } 

     else if (segue.identifier == "button3Segue"){ 
      buttonSelected = 3 
     } 

     else if (segue.identifier == "button4Segue") { 
      buttonSelected = 4 
     } 

     NSUserDefaults.standardUserDefaults().setInteger(buttonSelected, forKey: "buttonSelected") // Save the selection in user defaults 
     NSUserDefaults.standardUserDefaults().synchronize() // Save changes 

     print("runs") 

     if buttonSelected == 1 { 
      let welcomeVC: UIViewController = self.storyboard!.instantiateViewControllerWithIdentifier("ONW") as UIViewController 
      self.parentViewController?.presentViewController(welcomeVC, animated: true, completion: nil) 
     } 

     if buttonSelected == 2 { 
      let welcomeVC: UIViewController = self.storyboard!.instantiateViewControllerWithIdentifier("OE") as UIViewController 
      self.parentViewController?.presentViewController(welcomeVC, animated: true, completion: nil) 
     } 

     if buttonSelected == 3 { 
      let welcomeVC: UIViewController = self.storyboard!.instantiateViewControllerWithIdentifier("OS") as UIViewController 
      self.parentViewController?.presentViewController(welcomeVC, animated: true, completion: nil) 
     } 

     if buttonSelected == 4 { 
      let welcomeVC: UIViewController = self.storyboard!.instantiateViewControllerWithIdentifier("ON") as UIViewController 
      self.parentViewController?.presentViewController(welcomeVC, animated: true, completion: nil) 
     } 
    } 
} 

Answer 1

是的，這是可能的。

1）你已經知道被按下哪個按鈕，這樣就得到這些信息。在prepareForSegue（）或按鈕的IBAction中執行此操作（如果有）。

2）保存在用戶的默認

3）的值當你的應用程序啓動，讀取用戶的默認鍵和顯示正確的視圖控制器。

下面是如何保存的信息：

override func prepareForSegue(segue: UIStoryboardSegue, sender: AnyObject!) { 

     var buttonSelected: Int = 0 

     if (segue.identifier == "button1Segue") { 

      buttonSelected = 1 
     } 

     else if (segue.identifier == "button2Segue") { 

      buttonSelected = 2 
     } 

     // Etc . . . 

     NSUserDefaults.standardUserDefaults().setInteger(buttonSelected, forKey: "buttonSelected") // Write the selection in user defaults 
     NSUserDefaults.standardUserDefaults().synchronize() // Save changes 
    } 

這裏有一種方法可以選擇的路徑：

func application(application: UIApplication, didFinishLaunchingWithOptions launchOptions: [NSObject: AnyObject]?) -> Bool { 
     let buttonSelected = NSUserDefaults.standardUserDefaults().integerForKey("buttonSelected") 

     if buttonSelected != 0 { 

      let storyboard = UIStoryboard(name: "Main", bundle: nil) 
      let vcName = "" 

      switch buttonSelected { 
      case 1: 
       vcName = "Button1Controller" 
      case 2: 
       // Etc 
      } 

      let vc = storyboard.instantiateViewControllerWithIdentifier(vcName) 
      self.window?.rootViewController?.presentViewController(vc, animated: true, completion: nil) 
     } 
     else { 
     // The user default wasn't saved yet 
     } 
    return true 
} 

Answer 2

我希望這將到

@IBAction func saveButton(sender: UIButton) 
{ 
    let defaults = NSUserDefaults.standardUserDefaults() 
    defaults.setBool(true, forKey: "button1") 
    defaults.synchronize() 
} 

您檢查按鈕會這樣

func application(application: UIApplication, willFinishLaunchingWithOptions launchOptions: [NSObject : AnyObject]?) -> Bool { 

    let prefs = NSUserDefaults.standardUserDefaults() 
    if let prefs.boolForKey("button1") == true {   
     // here code if button was clicked 
    } else {   
     // here code if button was not clicked 
    } 

    return true 
    }