objective c - Audio playing while app in background iOS -

i have app based around core bluetooth. when specific happens, app woken using core bluetooth background modes , fires off alarm, can't alarm working when app not in foreground.

i have alarm singleton class initialises avaudioplayer this:

nsurl *url = [nsurl fileurlwithpath:[[nsbundle mainbundle]                     pathforresource:soundname                              oftype:@"caf"]];  self.player = [[avaudioplayer alloc] initwithcontentsofurl:url error:nil]; [[avaudiosession sharedinstance] setcategory:avaudiosessioncategoryplayback error:nil]; [[avaudiosession sharedinstance] setactive: yes error: nil]; [self.player preparetoplay]; self.player.numberofloops = -1; [self.player setvolume:1.0];  nslog(@"%@", self.player); 

this method called when alarm code called:

-(void)startalert {     nslog(@"%s", __function__);      playing = yes;     [self.player play];     nslog(@"%i", self.player.playing);      if (vibrate) {         [self vibratepattern];     } } 

now when app in foreground, self.player.playing returns 1 when app in background self.player.playing returns 0. why be? code being called, app awake , functioning. vibrate works uses audioservicesplaysystemsound(ksystemsoundid_vibrate);

any idea why sound won't play?

thanks

i have app needs background audio app works app background mode "voice on ip" needs record sometimes. play background audio telling app singleton need play audio in background:

uibackgroundtaskidentifier newtaskid = uibackgroundtaskinvalid; if([theplayer play]){     newtaskid = [[uiapplication sharedapplication] beginbackgroundtaskwithexpirationhandler:null];    } 

edit: must call [[uiapplication sharedapplication] beginbackgroundtaskwithexpirationhandler:null]; before app goes background. in app, @ same time start playing, in yours, if player might started in background, should do:

- (void)applicationdidenterbackground:(uiapplication *)application{   // should retain newtaskid check background tasks , finish them    newtaskid = [[uiapplication sharedapplication] beginbackgroundtaskwithexpirationhandler:null];    }