iOS App crashes on button tap in Swift -

i new swift. having small problem iboutlet button action. when click button app crashes. scenario under:

in default viewcontroller.swift:

override func viewdidload() {     super.viewdidload()     var mv = mycontroller(nibname:"mycontroller",bundle:nil);     self.view.addsubview(mv.view); } 

my iboutlet button in mycontroller.swift loads different .xibs per device screen size. have added button action on mycontroller under:

@ibaction func test(sender:anyobject){      nslog(" hello "); } 

and here xib looks like:

now when click app crashes. clue guys?

i recommend recreate button in way

1) drag button storyboard. next, select assistant editor @ top right hand corner of xcode , navigate view controller code.

2) select show document outline located @ bottom part of storyboard , click on button. next use ctrl click code , under connection, selectibaction

3) under new block of code generated ibaction, use println("is working?") , run on ios simulator. should work fine tried on new project.