Receiving Apple Push Notifications when app is in background - xcode

Question

I have implemented push notifications in my iOS8 app. I am trying to play an audio file once the notification is received.
The code is playing the audio when the app is in the foreground, but when the app is in the background, nothing happens.
I have tried regenerating the certificates and provisioning profiles. And I have made sure that the app is running in the background, i.e. the user has not swiped up to remove it. In Background modes, I have enabled Remote Notifications, Background Fetch and Audio & Airplay.
I have added code snippets from my AppDelegate.m file:
- (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions {
// More code here ---------------------------------------------------
if (launchOptions) {
NSDictionary *userInfo = [launchOptions valueForKey:UIApplicationLaunchOptionsRemoteNotificationKey];
NSDictionary *apsInfo = [userInfo objectForKey:#"aps"];
if (apsInfo) { //apsInfo is not nil
[self performSelector:#selector(playCarAlarmAudio)
withObject:nil
afterDelay:1];
}
}
if ([[[UIDevice currentDevice] systemVersion] floatValue] >= 8.0) {
[[UIApplication sharedApplication] registerForRemoteNotifications];
UIUserNotificationSettings *settings = [UIUserNotificationSettings settingsForTypes:(UIUserNotificationTypeBadge
|UIUserNotificationTypeSound
|UIUserNotificationTypeAlert) categories:nil];
[[UIApplication sharedApplication] registerUserNotificationSettings:settings];
}
// More code here ---------------------------------------------------
}
The delegate methods to handle push notifications:
-(void) application:(UIApplication *)application didFailToRegisterForRemoteNotificationsWithError:(NSError *)error {
NSLog(#"Failed to register for push");
}
-(void) application:(UIApplication *)application didRegisterUserNotificationSettings:(UIUserNotificationSettings *)notificationSettings {
}
-(void) application:(UIApplication *)application didReceiveRemoteNotification:(NSDictionary *)userInfo {
[self respondToEventNotification:userInfo];
}
-(void) application:(UIApplication *)application didReceiveRemoteNotification:(NSDictionary *)userInfo fetchCompletionHandler:(void (^)(UIBackgroundFetchResult))completionHandler {
// [self respondToEventNotification:userInfo];
[self playAlarmAudio];
}
-(void) respondToEventNotification : (NSDictionary *) userInfo {
if ([[UIApplication sharedApplication] applicationState] == UIApplicationStateBackground) {
UILocalNotification *localNotification = [[UILocalNotification alloc] init];
[localNotification setSoundName:#"alarm.mp3"];
[localNotification setFireDate:[NSDate date]];
[[UIApplication sharedApplication] scheduleLocalNotification:localNotification];
}
else if ([[UIApplication sharedApplication] applicationState] == UIApplicationStateActive) {
[self playAlarmAudio];
}
}
And to play the Alarm:
-(void) playAlarmAudio {
NSString *filePath = [[NSBundle mainBundle] pathForResource:#"alarm" ofType:#"mp3"];
NSURL *fileUrl = [NSURL fileURLWithPath:filePath];
self.audioPlayer = [[AVAudioPlayer alloc] initWithContentsOfURL:fileUrl error:nil];
self.audioPlayer.numberOfLoops = 1;
[self.audioPlayer play];
}

Answer 1

According to the following Apple documentation, the notification sound to be played is specified inside the notification payload dictionary (https://developer.apple.com/library/ios/documentation/NetworkingInternet/Conceptual/RemoteNotificationsPG/Chapters/ApplePushService.html):
The Notification Payload
Each remote notification includes a payload. The payload contains information about how the system should alert the user as well as any custom data you provide. In iOS 8 and later, the maximum size allowed for a notification payload is 2 kilobytes; Apple Push Notification service refuses any notification that exceeds this limit. (Prior to iOS 8 and in OS X, the maximum payload size is 256 bytes.)
For each notification, compose a JSON dictionary object (as defined by RFC 4627). This dictionary must contain another dictionary identified by the key aps. The aps dictionary can contain one or more properties that specify the following user notification types:
An alert message to display to the user
A number to badge the app icon with
A sound to play