iOS development from getting started to mastering--uiviewcontroller use

Uiviewcontroller use: Jump from viewcontroller.m to viewcontroller02.m,viewcontroller.m life cycle problem, ViewController02 disappear and then show Viewcontroller process
VIEWCONTROLLER.M inside the code:

#import "ViewController.h" #import "ViewController02.h"  @interface viewcontroller ()@end @implementation viewcontroller //When the screen is clicked, call this function- (void) Touchesbegan: (Nsset<uitouch *> *) touches withevent: (uievent *) event{//Create a View controller 2ViewController02 *VC =[[viewcontroller02 Alloc]init];//Display a new view controller to the screen    //P1: New View Controller Object    //P2: Using animations to toggle animation effects    //P3: Function call after switching over, no direct nil transfer required[ SelfPRESENTVIEWCONTROLLER:VC Animated:YESCompletion:Nil];}//The first time the program loads the view is called- (void) Viewdidload {[SuperViewdidload];additional setup after loading the view, typically from a nib.     Self. View. BackgroundColor=[UicolorBluecolor];NSLog(@"Viewdidload load view for the first time");}Call this function when the view controller's view is about to be displayed//View divided into: 1 before display (not shown) 2 is in the display state 3 is already hidden//Parameter: Indicates whether the display is switched after animation//Each time the view is displayed, it will be called- (void) Viewwillappear: (BOOL) animated{NSLog(@"Viewwillappear view is about to be displayed");}//When the view is about to disappear, call this function//Parameter: Indicates whether the animation switch disappears after the call//Current status: View or display on screen- (void) Viewwilldisappear: (BOOL) animated{NSLog(@"Viewdiddisappear view is about to disappear");}Call this function immediately after the view has been displayed to the screen//Parameter: Indicates whether to invoke animation toggle display//Current status: Already displayed on the screen- (void) Viewdidappear: (BOOL) animated{NSLog(@"The Viewdidappear view has been displayed");}//The current view has disappeared from the screen//Parameter: Indicates whether the animation is invoked//Current status: The current View control view has disappeared from the screen- (void) Viewdiddisappear: (BOOL) animated{NSLog(@"Viewdiddisappear view has disappeared");} - (void) Didreceivememorywarning {[SuperDidreceivememorywarning];//Dispose of any resources, can be recreated.}@end

To create a ViewController02, the code in the VIEWCONTROLLER02.M is as follows:

#import "ViewController02.h"  @interface ViewController02 ()@end @implementation ViewController02 - (void) Viewdidload {[SuperViewdidload];additional setup after loading the view.    //Controller 2 is in red color     Self. View. BackgroundColor=[UicolorRedcolor];}//When you click on the interface screen of the current controller 2- (void) Touchesbegan: (Nsset<uitouch *> *) touches withevent: (uievent *) event{//Make the current controller disappear    //P1: Whether there is an animation effect    //P2: Whether to invoke the function block block operation after the end[ SelfDismissviewcontrolleranimated:YESCompletion:Nil];} - (void) Didreceivememorywarning {[SuperDidreceivememorywarning];//Dispose of any resources, can be recreated.}/ * #pragma mark-navigation//in a storyboard-based application, you'll often want to do a little preparation before navigation-(void) Prepareforsegue: (Uistoryboardsegue *) Segue Sender: (ID) Sender {//Get the new view controller using    [Segue Destinationviewcontroller]. Pass the selected object to the new view Controller.} */@end

iOS development from getting started to mastering--uiviewcontroller use