AVPlayer streaming audio in background - ios

I have a problem with the AVPlayer playing in background mode, like a lot of people here and everywhere on the web. I've done what I think is supposed to work, but is still doesn't... I think my problem might be where I set and use my AudioSession and AVPlayer.
1) The "audio" key is in UIBackgroundModes of my Info.plist
2) AudioSession set like this in AppDelegate (initialised in didFinishLaunchingWithOptions):
AVAudioSession *audio = [[AVAudioSession alloc]init];
[audio setCategory:AVAudioSessionCategoryPlayback error:nil];
[audio setActive:YES error:nil];
3) I use an AVPlayer (not AVAudioPlayer) also implemented in AppDelegate. (initialised in didFinishLaunchingWithOptions, after the AudioSession), right after the AudioSession
// Load the array with the sample file
NSString *urlAddress = #"http://mystreamadress.mp3";
//Create a URL object.
self.urlStream = [NSURL URLWithString:urlAddress];
self.player = [AVPlayer playerWithURL:urlStream];
//Starts playback
[player play];
And still, the audio is suspended everytime the app goes in background (when I press the "Home" button).


By the way, the problem was just with the simulator. Works fine on the iOS devices

Related

Playing in AVPlayer causes UI freezing

I am doing an iOS application with a video player in it. I have to change my video URL each time user switch it view angle. But when I am switching to a new URL my UI gets freezed for some time. Following is my code for switching video URL function.
// Create the AVPlayer using the playeritem
m_pMoviePlayer = [AVPlayer playerWithURL:[NSURL URLWithString:pUrl]];
NSError *_error = nil;
[[AVAudioSession sharedInstance] setCategory: AVAudioSessionCategoryPlayback error: &_error];
m_pMoviePlayer.allowsExternalPlayback = NO;
// You can play/pause using the AVPlayer object
[m_pMoviePlayer play];
[self registerMoviePlayerObservers];
Thanks in advance.

Audio playing while app in background iOS

I have an app mostly based around Core Bluetooth.
When something specific happens, the app is woken up using Core Bluetooth background modes and it fires off an alarm, however I can't get the alarm working when the app is not in the foreground.
I have an Alarm Singleton class which initialises AVAudioPlayer like 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 is the method that is called when my alarm code is called:
-(void)startAlert
{
NSLog(#"%s", __FUNCTION__);
playing = YES;
[self.player play];
NSLog(#"%i", self.player.playing);
if (vibrate) {
[self vibratePattern];
}
}
Now when the app is in the foreground, self.player.playing returns 1 however when the app is in the background self.player.playing returns 0. Why would this be?
All the code is being called, so the app is awake and functioning.
The vibrate works perfectly which uses AudioServicesPlaySystemSound(kSystemSoundID_Vibrate);
Any idea why this sound won't play?
Thanks

Apple has a nice Technical Q&A article about this in its documentation (see also Playing and Recording Background Audio).
I think one big thing missing is that you haven't activated the Audio Background Mode in the Xcode settings:
Maybe also adding [self.player prepareToPlay] in your alert method is helpful.

I have an App than also needs background audio but my App works with the App background mode "Voice over IP" as it needs to record sometimes. I play background audio telling the App singleton I need to play audio in background:
UIBackgroundTaskIdentifier newTaskId = UIBackgroundTaskInvalid;
if([thePlayer play]){
newTaskId = [[UIApplication sharedApplication] beginBackgroundTaskWithExpirationHandler:NULL];
}
EDIT: You must call [[UIApplication sharedApplication] beginBackgroundTaskWithExpirationHandler:NULL]; before your app goes to background. In my app, it is at the same time you start playing, in yours, if the player might be started in background, you should do:
- (void)applicationDidEnterBackground:(UIApplication *)application{
// You should retain newTaskId to check for background tasks and finish them
newTaskId = [[UIApplication sharedApplication] beginBackgroundTaskWithExpirationHandler:NULL];
}

Apple docs
Either enable audio support from the Background modes section of the Capabilities tab
Or enable this support by including the UIBackgroundModes key with the audio value in your app’s Info.plist file

I take it you have the audio background mode specified for the app. Even so, I'm not sure you can set an audio session to be active while in the background. You need to have activated it before going into the background. You may also need to play some silent audio to keep this active, but this is seems like bad practice (it may drain the battery). Looking at the docs for notifications there seems to be a way to have a local notification play an audio sample that's included in your bundle, which seems to be what you want to do, so maybe that's the way to go.

Try this :
[[AVAudioSession sharedInstance] setCategory:AVAudioSessionCategoryAmbient error:nil];
link
Try this http://www.sagorin.org/ios-playing-audio-in-background-audio/

You need to enable your app to handle audiosession interruptions (and ended interruptions) while in the background. Apps handle audio interruptions through notification center:
First, register your app with the notification center:
- (void) registerForMediaPlayerNotifications {
[notificationCenter addObserver : self
selector: #selector (handle_iPodLibraryChanged:)
name: MPMediaLibraryDidChangeNotification
object: musicPlayer];
[[MPMediaLibrary defaultMediaLibrary] beginGeneratingLibraryChangeNotifications];
}
Now save player state when interruption begins:
- (void) audioPlayerBeginInterruption: player {
NSLog (#"Interrupted. The system has paused audio playback.");
if (playing) {
playing = NO;
interruptedOnPlayback = YES;
}
}
And reactivate audio session and resume playback when interruption ends:
-(void) audioPlayerEndInterruption: player {
NSLog (#"Interruption ended. Resuming audio playback.");
[[AVAudioSession sharedInstance] setActive: YES error: nil];
if (interruptedOnPlayback) {
[appSoundPlayer prepareToPlay];
[appSoundPlayer play];
playing = YES;
interruptedOnPlayback = NO;
}
}
Here's Apple's sample code with full implementation of what you're trying to achieve:
https://developer.apple.com/library/ios/samplecode/AddMusic/Introduction/Intro.html#//apple_ref/doc/uid/DTS40008845

I was also facing the same problem, but i was only facing it only during initial time when i was trying to play a sound while app was in background, once the app comes in foreground and i play the sound once than it works in background also.
So as soon as app is launched/ login is successful in my case, i was running this code:
[self startRingcall];
dispatch_after(dispatch_time(DISPATCH_TIME_NOW, (int64_t)(3.0f * NSEC_PER_SEC)), dispatch_get_main_queue(), ^{
[self stopRingcall];
});
- (void)startRingcall
{
if( self.audioPlayer )
[self.audioPlayer stop];
NSURL* musicFile = [NSURL fileURLWithPath:[[[UILayer sharedInstance] getResourceBundle] pathForResource:#"meetcalling" ofType:#"caf"]];
NSError *error;
self.audioPlayer = [[AVAudioPlayer alloc] initWithContentsOfURL:musicFile error:&error];
[[AVAudioSession sharedInstance] setCategory:AVAudioSessionCategoryPlayback error:nil];
[[AVAudioSession sharedInstance] setActive: YES error: nil];
if (error != nil) {
NSLog(#"meetringer sound error -> %#",error.localizedDescription);
}
self.audioPlayer.volume = 0;
[self.audioPlayer play];
self.audioPlayer.numberOfLoops = 1;
}
- (void)stopRingcall
{
if( self.audioPlayer )
[self.audioPlayer stop];
self.audioPlayer = nil;
}

UIWebview radio stream plays in background?

I'm new into Apple developing but I need to make an easy Radio Streaming App. I've made everything and the app works correctly on my iPhone (with IOS 6) but it stops playing when I'm pushing home button (when the app goes into background mode). Is there any posibility to make the Webview work in background?

You will need to go to your Project, then the Capabilities tab, then turn on the Background Modes and toggle on the one for background audio. You will also need to set your audio session to the playback category
[[AVAudioSession sharedInstance] setCategory:AVAudioSessionCategoryPlayback withOptions:nil error:nil];

You need to use the AVAudioPlayer class.
NSURL *url = [NSURL URLWithString:#"http://puttheurlhere.com"];
NSData *data = [NSData dataWithContentsOfURL:url];
AVAudioPlayer *audioPlayer = [[AVAudioPlayer alloc] initWithData:data error:nil];
[audioPlayer play];

Audio feed back in foreground and background

I have to give audio feedback when my app is in foreground and also in background. But when the app enters background audio feedback is not heard. In info.plist I have set background mode to App plays audio or streams audio/video using AirPlay and used the following but the audioPlayerDidFinishPlaying delegate is not called when app enters background and audio is not heard.
AVAudioPlayer *sound = [[AVAudioPlayer alloc] initWithContentsOfURL:url error:&err];
sound.delegate = self;
///Fixed the issue No audible feedback when main audio is silent
[[AVAudioSession sharedInstance] setCategory:AVAudioSessionCategoryPlayback error:nil];
[[AVAudioSession sharedInstance] setActive: YES error: nil];
// This is necessary if you want to play a sequence of songs, otherwise your app will be
// killed after the first one finishes.
[[UIApplication sharedApplication] beginReceivingRemoteControlEvents];
[soundQueue addObject:sound];

You need to make couple of changes in plist file.
1) Set Required background mode to App plays audio
2) set Application does not run in background to YES.
NSError *setCategoryErr = nil;
NSError *activationErr = nil;
[[AVAudioSession sharedInstance] setCategory: AVAudioSessionCategoryPlayback error:&setCategoryErr];
[[AVAudioSession sharedInstance] setActive:YES error:&activationErr];
Then, you need to write these much code in AppDelegate
Now, you can easily run audio while phone screen locks or in background.
It works fine for me. :)
for more please refer to Playing Audio in background mode and Audio Session Programming Guide

iOS AVAudioPlayer sound stops playing when screen is locked

I’ve read many articles/posts on this topic, but I’m still unable to play a sound while the screen is locked.
In viewDidLoad, I initialize the audio session and set the audio property to kAudioSessionCategory_MediaPlayback:
AudioSessionInitialize(NULL, NULL, interruptionListenerCallback, self);
UInt32 sessionCategory = kAudioSessionCategory_MediaPlayback;
AudioSessionSetProperty(kAudioSessionProperty_AudioCategory, sizeof(sessionCategory), &sessionCategory);
AudioSessionSetActive(true);
I then initialize my AVAudioPlayer variable (audioPlayer):
NSString *soundFilePath = [[NSBundle mainBundle] pathForResource: #"click" ofType: #"wav"];
NSURL *fileURL = [[NSURL alloc] initFileURLWithPath: soundFilePath];
NSError *error;
audioPlayer = [[AVAudioPlayer alloc] initWithContentsOfURL: fileURL error: &error];
[fileURL release];
I added “App plays audio” to a “Required background modes” section of my info.plist.
I added AVAudioPlayerDelegate and AVAudioSessionDelegate to my view controller’s *.h file (although I don’t know if that was necessary).
I play the (very short) sound periodically (~1x per second):
[audioPlayer play]
The sound plays fine when the screen is unlocked, but stops playing when I lock it. When I then unlock the screen, the (queued) sounds are played.
Ideas? Thanks!

Thanks holex:
I got "App plays audio" from http://mobile.tutsplus.com/tutorials/iphone/ios-sdk_background-audio/.
If you add a row with UIBackgroundModes to the plist, it's automatically populated and includes this and six other background modes. If you Google "App plays audio" and UIBackgroundModes you'll see plenty of hits.
[I would have replied via a Comment rather than an Answer, but alas, I don't have the reputation.]

It seems the problem is that I'm starting to play the sound after the screen has been locked. That's mostly answered in How to play sounds in locked mode on iPhone.

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