How to support to play audio file in the background - audio

Question

There is a function in my project to support playing a new audio file even in the background status.I use the MPMoviePlayerController class to play audio files.
But I found it was started in the active status，then it would continue playing the same audio(if the audio file wasn't finished) in the background status；But it won't start a new audio in the background status.
How can I to support playing a new audio in the backgound status？
I found the music player of the iphone can support playing a new audio in the background status，when set runloop or random PlayMode.
The following is my code to prove the appearance in fact:
(void)applicationDidEnterBackground:(UIApplication *)application
{
if (pCotnroller1) {
[pCotnroller1 release];
}
pCotnroller1 = [[MPMoviePlayerController alloc] initWithContentURL:[NSURL URLWithString:#"http://r.yhiker.com:9001/0086/32/05/060009/Data/6/00863205060009006_24Kbps.mp3"]];
pCotnroller1.shouldAutoplay = YES;
[pCotnroller1 play];
//it wasn't played here
}
(void)applicationWillEnterForeground:(UIApplication *)application
{
// Called as part of the transition from the background to the active state; here you can undo many of the changes made on entering the background.
if (pCotnroller1) {
switch (pCotnroller1.playbackState) {
case MPMoviePlaybackStateStopped:
NSLog(#"播放地址");
break;
case MPMoviePlaybackStatePaused:
NSLog(#"播放暂停");
break;
case MPMoviePlaybackStateInterrupted:
NSLog(#"播放中断");
break;
case MPMoviePlaybackStateSeekingBackward:
break;
case MPMoviePlaybackStateSeekingForward:
break;
default:
break;
}
if (pCotnroller1.playbackState == MPMoviePlaybackStatePlaying) {
//it will come here,and play autoed here
// [pCotnroller1 play];
}
else
{
}
}
}

Answer 1

I tried some ways which was found in the net，but it didn't work.Some one had used this way to solute his question.I didn’t know why.
the following is my code：
- (void)applicationDidEnterBackground:(UIApplication *)application
{
[application beginReceivingRemoteControlEvents];
[self updateUserLocation];
}
- (void)updateUserLocation
{
if (!pCotnroller1) {
// pCotnroller1 = [[MPMoviePlayerController alloc] initWithContentURL:[NSURL URLWithString:#"http://r.yhiker.com:9001/0086/32/05/PP0041/Data/13/00863205PP0041013_24Kbps.mp3"]];
NSString *audioDiskPath = [HelpTools returnSpotAudioDiskPath:#"00863205PP0041013"];
pCotnroller1 = [[MPMoviePlayerController alloc] initWithContentURL:[NSURL fileURLWithPath:audioDiskPath/*#"/var/mobile/Applications/E7A06CB2-0856-407D-ABA1-2A846B65CD9D/Library/Caches/Data/0086/32/05/PP0041/Data/13/00863205060005016_24Kbps.mp3"*/]];
pCotnroller1.shouldAutoplay = YES;
if ([UIApplication sharedApplication].applicationState == UIApplicationStateBackground) {
[pCotnroller1 play];
NSLog(#"进入后台");
UIApplication *app = [UIApplication sharedApplication];
UIBackgroundTaskIdentifier taskID = [app beginBackgroundTaskWithExpirationHandler:nil];
if (bgTask != UIBackgroundTaskInvalid) {
[app endBackgroundTask:bgTask];
NSLog(#"允许后台播放");
}
bgTask = taskID;
}
else
{
NSLog(#"飞后台进行播放");
[pCotnroller1 play];
}
}
}
the console print:
2013-03-18 16:20:11.844 Sz[1665:907] [MPAVController] Autoplay: Disabling autoplay for pause
2013-03-18 16:20:11.845 Sz[1665:907] [MPAVController] Autoplay: Disabling autoplay
2013-03-18 16:20:13.489 Sz[1665:907] 文件存在
2013-03-18 16:20:18.017 Sz[1665:907] [MPAVController] Autoplay: Skipping autoplay, disabled (for current item: 1, on player: 0)
2013-03-18 16:20:18.998 Sz[1665:907] 进入后台
2013-03-18 16:20:21.269 Sz[1665:907] 播放地址
2013-03-18 16:20:26.251 Sz[1665:907] [MPAVController] Autoplay: Enabling autoplay
2013-03-18 16:20:26.307 Sz[1665:907] [MPAVController] Autoplay: Likely to keep up or full buffer: 0
2013-03-18 16:20:26.309 Sz[1665:907] [MPAVController] Autoplay: Skipping autoplay, not enough buffered to keep up.
2013-03-18 16:20:26.319 Sz[1665:907] [MPAVController] Autoplay: Enabling autoplay
2013-03-18 16:20:26.338 Sz[1665:907] [MPCloudAssetDownloadController] Prioritization requested for media item ID: 0