不能在`storyboard.instantiateViewController`之后下调

Question

I'm using storyboard.instantiateViewController to start a TableViewController, but when I try to downcast it, I get an error:

Could not cast value of type 'UITableViewController' (0x109b30de8) to 'PresenceTableViewController' (0x1060329f0).

My class PresenceTableViewController is a subclass of UITableViewController, and the storyboard has assigned the VC class correctly.

So why would this fail?

presenceViewController = storyboard.instantiateViewController(withIdentifier: "userPresenceTable") as! PresenceTableViewController

Answer 1

I tried the possible cases for "Could not cast value..." and it was woking fine for all cases, and then I generated this error in one case when module was not inherited from target. This solved the problem for me.

Just re-enter the class type on storyboard, it will automatically select "Inherit module from target". This would solve your problem.

Answer 2

Also make sure that your controller from you want to use must be embed with navigation bar

 let tableviewController = self.storyboard?.instantiateViewController(withIdentifier: "tableviewController") as! tableviewController
 self.navigationController?.pushViewController(tableviewController, animated: true)