ios - How to show alert view once in view controller in Swift 3? -


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i creating app when user enters page, alert view pops saying "click on button proceed". how can make alert view show once in view controller? help. 

override func viewdidappear(_ animated: bool) {     super.viewdidappear(animated)      let alertcontroller = uialertcontroller(title: "info", message: "click on button proceed", preferredstyle: uialertcontrollerstyle.alert)     let mybacksign = uialertaction(title: "ok", style: uialertactionstyle.default, handler: nil)     alertcontroller.addaction(mybacksign )     self.present(alertcontroller, animated: true, completion: nil) }

viewwillappear , viewdidappear called every time view displayed.

if want call method invoked once viewdidload.

viewdidload called once when view loaded memory.

use viewdidload.


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