Background applications specifically audio

[JamieReid]

Hi all, new to the forum and hoping someone can help me with this.

I have created an extension that takes advantage of a class called AudioStreamer (https://github.com/mattgallagher/AudioStreamer/).

I have it all working. We can play the streams no problem.

I have modified the plist settings so that:
Application does not run in background = No
Required background modes:
- Item 0 = App plays audio

Now when you press the home button, no audio is heard.

Bringing up the task manager shows the application is running.

Re-opening the app, the stream has not stopped playing and has been playing in the background but the sound couldn't be heard.

Has anyone got any suggestions?

[Anders]

Hi Jamie!
I'm think Francois knows more about the iOS audio than I do, but I think you need to have a look at audio session and interuption handling:
http://developer.apple.com/library/i...roduction.html

Otherwise you need to listen in on iOS system events (like when the app is paused or resumed in the background). There is now a way to subscribe to them by using these methods in CRunApp:
-(void)registerForiOSEvents: (id<UIApplicationDelegate>)object;
-(void)unregisterForiOSEvents: (id<UIApplicationDelegate>)object;

Your object will then be forwarded any iOS system events in the UIApplicationDelegate protocol which you can decide to listen to or not (by implementing the methods)
http://developer.apple.com/library/i...Reference.html

You can then pause the audio when the app is brought to the background and resume it again when it is resumed depending on what you want.

[JamieReid]

To be honest, I want it to continue playing in the background. I will read the docs tomorrow and post if I have any questions.

Problem is AudioStreamer doesn't use the standard audio from iOS, I had problems implementing those. So the normal delegate for AVPlayer/AVSession classes won't help.

I'll come back with more info tomorrow. Thanks

[JamieReid]

Francois or Andos, would you be able to help with this?

I have gone through all the documentation on the AudioSession and can verify that it is being set to the correct mode (One that plays when the screen locks and doesn't allow other audio, kAudioSessionCategory_MediaPlayback to be specific).

The AudioSession is set to active using AudioSessionSetActive(true).

It has also been set up to handle interuptions (i.e calls or alarms) using AudioSessionInitialize.

As far as I can see there is nothing more I can do to the AudioSession to ensure it runs in the background. This suggests that the app is being put in idle or something?

Do I need to implement both of your suggestions? I don't really see how registering for events will help... surely once AudioSession is set up correctly that will handle that side of things?

[Danny]

Andos, Francois - The audio stream needs to continue playing when the phone is locked or the app is sent to background, Jamie has implemented the KeepAlive functions, however I assume the MMF Runtime Pauses? I found this in the help file:

Application has been deactivated

This event is true at the moment when the application is going to the background (when the user presses the HOME button, or receives a phone call).
Please note that as the application is going into pause, only the code in the deactivated event will be executed before the app is reduced, any other code will be executed when the application is revived.
Application has been reactivated

This condition is called when the application is reactivated (for example if it was reduced and started again).

Going off this, I would assume that with the Runtime pausing it would cause the app to lose the stream as it can no longer buffer whilst in the background...

[Francois]

OK checked my code, I call AudioSessionSetproperty with parameter kAudioSessionCategory_SoloAmbientSound
From Apple's doc, the sound should be silenced by a ring, and screen locking. Does not allow sounds from other applications.
I am sure that if you change the AudioSessionProperty later than me, it will change the mode.

[UrbanMonk]

I've tried to do this myself. I've changed the audio mode, but I ran into the same issue.
I hope someone figures this out because I want to add the ability to keep audio from my app playing even after it is minimized.

I would also like to the ability to keep the ipod music playing when a MMF made app is started/running. That's basic functionality of all apps these days, so it's a shame that MMF doesn't support it yet.

[AyreGuitar]

UrbanMonk - I believe you can allow iPod music to play when MMF made app is running by making a small change in your XCode project. More details here: http://community.clickteam.com/showthread.php?t=69226

[OldSchool80s]

I may be misunderstanding this thread, but I think this comment is relevant:

The Pandora app allows for playing audio when phone is locked and screen is off.

So, iOS allows audio to be played when the screen is off and the phone is locked.

[Danny]

Yes, that's the gist OldSchool80's. Jamie has the source for another app which allows for the music to continue playing whilst in the background too, so atm this is our only priority to get this working.