I have some problems I init audio session and set this
[[AVAudioSession sharedInstance] setCategory:AVAudioSessionCategoryAmbient error:nil];
[[AVAudioSession sharedInstance]setActive:YES error:nil];
and
if ([[UIApplication sharedApplication] respondsToSelector:#selector(beginReceivingRemoteControlEvents)]){
[[UIApplication sharedApplication] beginReceivingRemoteControlEvents];
[self becomeFirstResponder];
}
So my problem is when I play music in background then remove app from task (double click on home btn) and then I press play on headphone my app start play audio but I expected play default player (default player was playing before start my app)
Related
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;
}
In Info.plist I added:
<key>UIBackgroundModes</key>
<array>
<string>audio</string>
<string>location</string>
</array>
...
I load the sound like this:
NSURL *urlFail = [NSURL fileURLWithPath:[NSString stringWithFormat:#"%#/criticalSound.wav", [[NSBundle mainBundle] resourcePath]]];
NSError *error;
audioPlayer = [[AVAudioPlayer alloc] initWithContentsOfURL:urlFail error:&error];
[audioPlayer setDelegate:self];
audioPlayer.numberOfLoops = 0;
[[AVAudioSession sharedInstance] setCategory:AVAudioSessionCategoryAmbient error:nil];
[audioPlayer setVolume:1.0];
if (audioPlayer == nil){
}else{
[[AVAudioSession sharedInstance] setCategory:AVAudioSessionCategoryAmbient error:nil];
[[AVAudioSession sharedInstance] setActive: YES error: nil];
[[UIApplication sharedApplication] beginReceivingRemoteControlEvents];
musicPlayer = [MPMusicPlayerController iPodMusicPlayer];
if (musicPlayer.playbackState == MPMusicPlaybackStatePlaying)
{
self.wasMusicAppOn = YES;
[musicPlayer pause];
}else{
self.wasMusicAppOn = NO;
}
[audioPlayer play];
}
This works fine when app is active.
But I have a location update when application is in background and from time to time (like when user pass 500m) I should play this sound.
So I put this code there.
Anyway problem is that sound plays when app is in foreground but doesn't work when it is in background.
What am I doing wrong here?
As far as I've been able to tell, you must actually be playing sound while going into the background to be able to continue playing sound in the background.
Also, the description for AVAudioSessionCategoryAmbient states that "Your audio is silenced by screen locking and by the Silent switch (called the Ring/Silent switch on iPhone)".
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
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
I am using AVAudioPlayer and NSFileHandle to do audio streaming. The basic idea is that I save the streaming audio data to the device with file system and then use AVAudioPlayer to playback the file just saved. AVAudioPlayer can still play that file even the streaming is in progress.
I have a UIButton to start streaming/downloading. When the downloaded data is accumulated to a specific amount of Bytes, AVAudioPlayer will play (the "play" method of AVAudioPlayer is triggered) automatically. My question is: I tap the button to start streaming/downloading, then press iPhone's home button very soon to make my app go to background. The download keeps working in the background but the "play" method of AVAudioPlayer returns "NO" which means the "play" method doesn't play the audio.
I added AVAudioSession related code to my audio player's init method:
- (id) initWithURL:(NSString *) downloadedMusicURL
{
if ((self = [super init]))
{
[[UIApplication sharedApplication] beginReceivingRemoteControlEvents];
CFURLRef url = CFURLCreateWithFileSystemPath (NULL, (CFStringRef)downloadedMusicURL, kCFURLPOSIXPathStyle, FALSE);
audioPlayer = [[AVAudioPlayer alloc] initWithContentsOfURL:CFBridgingRelease(url) error:nil];
AVAudioSession *session = [AVAudioSession sharedInstance];
[session setActive:YES error:nil];
[session setCategory:AVAudioSessionCategoryPlayback error:nil];
}
return self;
}
Also in the info.plist I added an item "App plays audio" for the Key "Required background modes". However, the "play" still doesn't get called properly in the background. What else did I miss? Thanks a lot in advance.
Your app cannot start playing audio in the background. And this makes sense. Think what the device would be like if an app that the user is not actively using could suddenly start producing sound! Remember, to the user, sending an app to the background is the naive equivalent of quitting that app. Your app must not rise like a zombie from the dead and start making noise!
The background audio setting allows your app that was producing audio while in the foreground to continue to do so when it then goes into the the background. It then can continue being in charge of the audio (if it receives remote events) until some other app produces sound; after that, your app is once again out of the running until it is brought to the foreground and produces sound.
So you'll need to start playing some sound before your app goes into the background, if you want this to work.
[[UIApplication sharedApplication] beginReceivingRemoteControlEvents];
UIBackgroundTaskIdentifier newTaskId = UIBackgroundTaskInvalid;
newTaskId = [[UIApplication sharedApplication] beginBackgroundTaskWithExpirationHandler:NULL];
/*
And
in info.Plist file
Required background modes : App PLAYS Audio
*/
Please use this code in - (void)applicationDidEnterBackground:(UIApplication *)application
UIApplication *app = [UIApplication sharedApplication];
UIBackgroundTaskIdentifier bgTask = 0;
bgTask = [app beginBackgroundTaskWithExpirationHandler:^{
[app endBackgroundTask:bgTask];
}];
AudioSessionSetActive(false);
and use this code in - (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions
AudioSessionInitialize (NULL,NULL,NULL,NULL);
UInt32 sessionCategory = kAudioSessionCategory_MediaPlayback;
AudioSessionSetProperty (kAudioSessionProperty_AudioCategory,sizeof (sessionCategory),&sessionCategory);
AudioSessionSetActive(true);
hope this helps.
Faced this very problem. Let me suggest you to use AVAudioSessionCategoryOptionMixWithOthers with -setCategory:withOptions:error:. Also, probably it makes sense to activate the session after you set the category, not before.
I have an AVPlayer to stream an mp3 file from the web. I have activated an AVAudioSession so that the audio will play when the app is exited / screen turned off. The music plays perfectly, but the little 'Play' triangle icon that appears in the status menu at the top of the phone is not appearing when the music is playing (as is the usual case in iOS). Anything I'm doing wrong? Code below
// Set AudioSession
NSError *sessionError = nil;
[[AVAudioSession sharedInstance] setDelegate:self];
[[AVAudioSession sharedInstance] setCategory:AVAudioSessionCategoryPlayback error:&sessionError];
[[AVAudioSession sharedInstance] setActive:YES error:nil];
//Direct audio to speakers when there is no headphone
UInt32 sessionCategory = kAudioSessionCategory_MediaPlayback;
AudioSessionSetProperty(kAudioSessionProperty_AudioCategory, sizeof(sessionCategory), &sessionCategory);
UInt32 audioRouteOverride = kAudioSessionOverrideAudioRoute_Speaker;
AudioSessionSetProperty (kAudioSessionProperty_OverrideAudioRoute,sizeof (audioRouteOverride),&audioRouteOverride);
For those who may come across this question, I figured it out. You have to make your player's controller the first responder - specifically for remote control events. Not only does this allow you to receive the remote control events (like the universal play/pause/forward/back controls), but it also puts the play icon in the status menu.
[[UIApplication sharedApplication] beginReceivingRemoteControlEvents];
[self becomeFirstResponder];