我正在使用此代码
NSURL *url = [NSURL fileURLWithPath:[NSString stringWithFormat:@"%@/audiofile.mp3", [[NSBundle mainBundle] resourcePath]]];
NSError *error;
player = [[AVAudioPlayer alloc] initWithContentsOfURL:url error:&error];
player.numberOfLoops = -1;
if (player == nil)
NSLog(@"%@",[error description]);
else
[player play];
但我想改变音量,所以我怎样才能得到音量细节?