init-Initialization Program
viewdidload-Load View
Called when the view of the Viewwillappear-uiviewcontroller object is about to join the window;
Called when the view of the Viewdidapper-uiviewcontroller object has been added to the window;
The view of the Viewwilldisappear-uiviewcontroller object is about to disappear, be overwritten, or be hidden when called;
The Viewdiddisappear-uiviewcontroller object's view has disappeared, is overwritten, or is hidden when called;
viewvillunload-when memory is too low, you need to release some views that you do not need to use when you are about to release the call;
Viewdidunload-called when the memory is too low to release some unwanted views.
Why manual Performseguewithidentifier does not take effect in IOS development:
Very simple: If you start Segue at Viewdidload, it will still be overwritten by the later filled view, if you start Segue in Viewdidappear after the view is loaded, OK!
IOS View controls the life cycle of an object Viewcontroller