objective c - Why the view doesn't show when I click the button in IOS? -

i new ios , , want implement album collectionview in ios.

when click filebrowserbutton button in first view , change second view(name:aitcameracollectionbrowser).

there has 2 button , collectionview in aitcameracollectionbrowser following picture.

and code of it's header file following code.

#import <uikit/uikit.h>  @interface aitcameracollectionbrowser : uiviewcontroller <uicollectionviewdelegate, uicollectionviewdatasource> @property (strong, nonatomic) iboutlet uibutton *backbutton; @property (strong, nonatomic) iboutlet uibutton *localalbumbutton; @property (strong, nonatomic) iboutlet uicollectionview *collectionview;  @end 

i have not load picture phone yet , should show view above picture when click change view button in first view.

the code of filebrowserbutton button following.

- (ibaction)filebrowserbutton:(id)sender {      uiviewcontroller *viewcontroller = nil ;      viewcontroller = [[aitcameracollectionbrowser alloc] initwithnibname:@"aitcameracollectionbrowser" bundle:nil] ;      viewcontroller.edgesforextendedlayout = uirectedgenone;      self.navigationitem.backbarbuttonitem = [[uibarbuttonitem alloc] initwithtitle:nslocalizedstring(@"back", nil) style: uibarbuttonitemstylebordered target:nil action:nil] ;     [self.navigationcontroller pushviewcontroller:viewcontroller animated:yes]; } 

the above code of button in first view no problem.

but doesn't show when click filebrowserbutton button , has backbarbuttonitem on top of screen.

so problem @ second view , , don't know why button , collectionview not show ?

in you're header, or .h file, add following code

- (ibaction)filebrowserbutton:(id)sender; 

next, in you're xib or storyboard file, have connect filebrowserbutton you're file's owner (by right-clicking yellow, transparent box on left of you're first picture) button, , choose touch inside.