SWRevealViewController无错误

Question

我正在使用SWRevealViewController

当我点击BackButton时出现此错误

fatal error: unexpectedly found nil while unwrapping an Optional value

  

我的代码

let nesne:SWRevealViewController = self.revealViewController()//the error here
let mainStroyBoard:UIStoryboard = UIStoryboard(name: "Main", bundle: nil)
let desController = mainStroyBoard.instantiateViewController(withIdentifier: "MessageViewController") as! MessageViewController
let newFrontViewController = UINavigationController.init(rootViewController:desController)
nesne.pushFrontViewController(newFrontViewController, animated: true)

Answer 1

  

溶液

let sw = storyboard?.instantiateViewController(withIdentifier: "SWRevealViewController") as! SWRevealViewController
self.view.window?.rootViewController = sw

let mainStroyBoard:UIStoryboard = UIStoryboard(name: "Main", bundle: nil)
let desController = mainStroyBoard.instantiateViewController(withIdentifier: "MessageViewController") as! MessageViewController
let newFrontViewController = UINavigationController.init(rootViewController:desController)
sw.pushFrontViewController(newFrontViewController, animated: true)