ios - elements of array are null -

i'm working along bignerdranch ios app book. in first chapter makes little quiz app questions hardcoded code file. if application runs successfully, it's supposed displaying question: "what blah blah?" in console, when run app says

displaying question: (null) 

in other words, (null) appearing instead of question array.

no errors showing when compile. wonder if has fact xcode using main.storyboard file rather xib , nib files, combined fact view controller uses method seems expect nib file, namely

- (id)initwithnibname:(nsstring *)nibnameornil bundle: 

any appreciated. code.

iosquizviewcontroller.h

#import <uikit/uikit.h>  @interface iosquizviewcontroller : uiviewcontroller 

iosquizviewcontroller.h

{     int currentquestionindex;      nsmutablearray *questions;     nsmutablearray *answers;      iboutlet uilabel *questionfield;     iboutlet uilabel *answerfield; }  - (ibaction)showanswer:(id)sender; - (ibaction)showquestion:(id)sender;  @end 

iosquizviewcontroller.m

#import "iosquizviewcontroller.h"  @interface iosquizviewcontroller ()  @end  @implementation iosquizviewcontroller  - (id)initwithnibname:(nsstring *)nibnameornil bundle:(nsbundle *)nibbundleornil {     self = [super initwithnibname:nibnameornil bundle:nibbundleornil];     if (self) {         questions = [[nsmutablearray alloc] init];         answers = [[nsmutablearray alloc] init];         [ questions addobject:@"what 7 +7"];         [ answers addobject:@"14"];          [questions addobject:@"what capital of vermont?"];         [answers addobject:@"montpelier"];          [questions addobject:@"from cognac made?"];         [answers addobject:@"grapes"];      }     return self; }  - (ibaction)showquestion:(id)sender {     currentquestionindex++;     if (currentquestionindex == [ questions count] ){         currentquestionindex = 0;     }     nsstring *question = [ questions objectatindex:currentquestionindex];     nslog(@"displaying question: %@", question);     [questionfield settext: question];     [answerfield settext:@"???"];  }  - (ibaction)showanswer:(id)sender {     nsstring *answer = [ answers objectatindex:currentquestionindex];      [answerfield settext:answer]; }   @end 

i deleted initwithnibname:bundle method , put code inside viewdidload

- (void)viewdidload {     if (self)     {         // create 2 arrays , make pointers point them         questions = [[nsmutablearray alloc] init];         answers = [[nsmutablearray alloc] init];          // add questions , answers array         [questions addobject:@"what 7 + 7?"];         [answers addobject:@"14"];          [questions addobject:@"what capital of vermont?"];         [answers addobject:@"montpelier"];          [questions addobject:@"what cognac made from?"];         [answers addobject:@"grapes"];     }  }