在plist文件中加入下面的字段:

需要先导入框架及代码中#import
- (void)applicationWillResignActive:(UIApplication*)application
{//将要进入后台
[[UIApplicationsharedApplication]beginReceivingRemoteControlEvents]; //让后台可以处理多媒体的事件
NSLog(@"%s",__FUNCTION__);
AVAudioSession *session =[AVAudioSession sharedInstance];
[session setActive:YES error:nil];
[session setCategory:AVAudioSessionCategoryPlaybackerror:nil];//后台播放
}
- (void)applicationDidEnterBackground:(UIApplication*)application
{//进入后台
NSLog(@"%s",__FUNCTION__);
NSString *musicPath =[[NSBundle mainBundle] pathForResource:@"我的歌声里"ofType:@"mp3"];
NSURL *url = [[NSURL alloc] initFileURLWithPath:musicPath];
AVAudioPlayer *player = [[AVAudioPlayer alloc] initWithContentsOfURL:url error:nil];
//创建播放器
AVAudioPlayer *audioPlayer = player;//赋值给自己定义的类变量
[urlrelease];
[player release];
[audioPlayer prepareToPlay];
[audioPlayer setVolume:1];
audioPlayer.numberOfLoops =-1; //设置音乐播放次数 -1为一直循环
if(audioPlayer)
{
[audioPlayer play]; //播放
}
AVAudioSession *session =[AVAudioSession sharedInstance];
[session setActive:YES error:nil];
[session setCategory:AVAudioSessionCategoryPlaybackerror:nil];
}