NSUnknownKeyException

Introduction

Today I followed the online tutorial to write the foodtruck application. I control+dragged the Lable to ViewController but then I found I didn’t change the button to action. Then I removed the line like this “ @IBOutlet weak var setDefaultLableText: UIButtonl!”. Then I got the following error:

2017-09-10 23:35:50.154 Foodtruck[4796:2553036] *** Terminating app due 
to uncaught exception 'NSUnknownKeyException', reason: 
'[<Foodtruck.ViewController 0x7fac0c6062b0> setValue:forUndefinedKey:]: 
this class is not key value coding-compliant for the key setefaultLableText.'

Solution

It is because: although code was deleted, it still needs to delete from the connect.

*Click the right part, there is an arraw (connection inspector)
*Delete the wrong connection
*Then it should work