title: iOS function similar ti viewDidLoad()
body: <p>I search a function (included in iOS or with external library) that is very similar to viewDidLoad(). The difference should be that the searched function will be used only when the App starts for the first time, that means when the user opened the App. ViewDidLoad() is used every time when the view was loaded. But the searched function xy() will only used when a view is loaded for the first time in the runtime.</p>
  
  <p><strong>This is the normal version</strong></p>
  
  <blockquote>
    <p>User opened App, View 1 opens -> ViewDidLoad() of view 1 -> User opens
    view 2 .... -> User goes back to View 1 -> ViewDidLoad() of View 1</p>
  </blockquote>
  
  <p><strong>I search this</strong></p>
  
  <blockquote>
    <p>User opened App, View 1 opens -> ViewDidLoad() of view 1 and function
    xy() -> User opens view 2 .... -> User goes back to View 1 ->
    ViewDidLoad() of View 1 (this time not function xy() because the view
    was already loaded in this runtime)</p>
  </blockquote>
  
  <p>Thanks for your help!</p>