How can I get the opposite value of a Bool in Swift?

Question

My specific case is I am trying to toggle the nav bar hidden and showing.

    let navHidden = !self.navigationController?.navigationBarHidden
    self.naviga         


        

Answer 1

navHidden is an optional. And you explictely unwrap that optional (which means you get a crash if navHidden is nil). Clearly something is wrong here. I suggest

if let navController = self.navigationController {
    let navHidden = navController.navigationBarHidden
    navController.setNavigationBarHidden (!navHidden, animated:true)
}