ios - swift subview does not full-fill parent view -

when app starts, use method set root view controller.

func showrootviewcontroller() {     let sb = uistoryboard.init(name: "main", bundle: nil)     let mainviewcontroller = sb.instantiateinitialviewcontroller()!     self.window?.rootviewcontroller = mainviewcontroller     self.window?.makekeyandvisible() } 

in main view controller, i've code set view container view

class mainviewcontroller: uiviewcontroller {      @iboutlet weak var headerview: uiview!     @iboutlet weak var containerview: uiview!      override func viewdidload() {         super.viewdidload()              }      override func viewdidappear(_ animated: bool) {         super.viewdidappear(animated)          if(usermanager.hasregistered()) {             let sb = uistoryboard.init(name: "login", bundle: nil)             self.setcontentviewcontroller(sb.instantiateinitialviewcontroller()!)         } else {             let sb = uistoryboard.init(name: "registration", bundle: nil)             self.setcontentviewcontroller(sb.instantiateinitialviewcontroller()!)         }      }      func setcontentviewcontroller(_ contentviewcontroller: uiviewcontroller) {         print(self.containerview.frame)         let contentview = contentviewcontroller.view!         contentview.frame = self.containerview.bounds         self.containerview.addsubview(contentview)     } } 

let @ view, have container view used add subviews. set background address frame of container view

the subview designed below:

the result not expected. containerview has gone somewhere (i don't know), subview move on top.

please me.

contentview frame setted in wrong position. should move line of code:

contentview.frame = self.containerview.bounds 

in

override func func viewdidlayoutsubviews() {     super.viewdidlayoutsubviews()     contentview.frame = self.containerview.bounds }