ios - Application tried to present a nil modal view controller on target when sending text -

i'm trying sent text message , have controller set so, error message 'nsinvalidargumentexception', reason: 'application tried present nil modal view controller on target <ally.textmessagecontroller: 0x7fd5361278e0>.' i've made sure in storyboard i'm connecting textmessagecontroller i'm not quite sure causing crash.

class textmessagecontroller: uiviewcontroller, mfmessagecomposeviewcontrollerdelegate {      var phone: string?     override func viewdidload() {         super.viewdidload()            print(phone)         var messagevc = mfmessagecomposeviewcontroller()          messagevc.body = "hey need help, available";         messagevc.recipients = ["555555555"]         messagevc.messagecomposedelegate = self;          presentviewcontroller(messagevc, animated: false, completion: nil)          // additional setup after loading view.     }       func cansendtext() -> bool {         return mfmessagecomposeviewcontroller.cansendtext()     }      func messagecomposeviewcontroller(controller: mfmessagecomposeviewcontroller!, didfinishwithresult result: messagecomposeresult) {          self.dismissviewcontrolleranimated(true, completion: nil)         switch (result.rawvalue) {         case messagecomposeresultcancelled.rawvalue:             print("message cancelled")             self.dismissviewcontrolleranimated(true, completion: nil)         case messagecomposeresultfailed.rawvalue:             print("message failed")             self.dismissviewcontrolleranimated(true, completion: nil)         case messagecomposeresultsent.rawvalue:             print("message sent")             self.dismissviewcontrolleranimated(true, completion: nil)         default:             break;         }     } 

here error message

'nsinvalidargumentexception', reason: 'application tried present nil modal view controller on target <ally.textmessagecontroller: 0x7fd5361278e0>.' 

you should first check whether device can send text message , present it. instance simulator can not send text message code crash in it. along simulator, user’s device may not set delivery of messages. perform following check

if messagevc.cansendtext() {     presentviewcontroller(messagevc, animated: false, completion: nil) }