问题
I have three view controllers which in the third one I have a picker view which it store data into core data, and when I press navigation bar back button I want second view controller to refresh it's labels from core data, but I don't know how Any suggestion ?
回答1:
Use NSFetchRequest() method in viewWillAppear() method in second view controller
来源：https://stackoverflow.com/questions/35578699/reloading-view-controller-when-navigation-bar-back-button-is-pressed-in-swift-2