ios - Termination because of NSEexception? -

this in .m file, xcode. main goal have button play sound(not @ same time) when has 2 sound files attached , randomizer doesn't play same sound twice or wouldn't twice. run code , when click on yes button lldb nsesception error occurs. ive looked around lldb exception error solution found go view-controller delete yellow exclamation mark;which didn't not solve issue..

       #import "viewcontroller.h"       #import <avfoundation/avaudioplayer.h>  @interface viewcontroller ()  @end   @implementation viewcontroller : uiviewcontroller   - (void)viewdidload  {   [super viewdidload]; // additional setup after loading view, typically nib.   }    - (void)didreceivememorywarning     {    [super didreceivememorywarning];   // dispose of resources can recreated.   }     - (ibaction)yes{   nsmutablearray *array=[nsmutablearray                        arraywithobjects:                        @"yes.mp3",                        @"yes 3.mp3",                         nil];   int i=0;  for(i=0;i<=[array count]; i++)   {      nsinteger rand=(arc4random() %1);     [array exchangeobjectatindex:i                withobjectatindex:rand];   }     nsstring *sound = [array objectatindex:i];    avaudioplayer* audioplayer=[[avaudioplayer alloc] initwithcontentsofurl:[nsurl fileurlwithpath:              [[nsbundle mainbundle]pathforresource:sound oftype:@"mp3"]] error:null];      [audioplayer play];   }   @end 

you have 4 issues. loop range, calculation of random value, , array index usage after loop, , specify sound file's extension twice.

the loop , random value should be:

for(nsuinteger = 0; < [array count]; i++) {     nsinteger rand = arc4random_uniform(array.count);     [array exchangeobjectatindex:i withobjectatindex:rand]; } 

1. notice <= <.
2. your calculation of random number returned 0.

it's unclear want sound value after loop. written, try access using i large. need specify value in range 0 array.count - 1.

if want 1st (now random) value array, use:

nsstring *sound = [array firstobject]; 

update:

after realizing want play 1 of 2 sounds randomly, think code can simplified to:

- (ibaction)yes {     nsinteger rand = arc4random_uniform(2);     nsstring sound = rand == 0 ? @"yes" : @"yes 3";     nsurl *url = [[nsbundle mainbundle] urlforresource:sound withextension:@"mp3"];      avaudioplayer* audioplayer = [[avaudioplayer alloc] initwithcontentsofurl:url error:nil];     [audioplayer play]; }