if (!m_reqfloorSoundID) {
NSString *floorSoundPath = [[NSBundle mainBundle] pathForResource:@"req_floor" ofType:@"wav"];
NSURL *floorSoundURL = [NSURL fileURLWithPath:floorSoundPath];
AVAudioPlayer *floorSoundPlayer = [[AVAudioPlayer alloc] initWithContentsOfURL:floorSoundURL error:nil];
[floorSoundPlayer prepareToPlay];
AudioServicesCreateSystemSoundID((CFURLRef)floorSoundURL, &m_reqfloorSoundID);
[floorSoundPlayer release];
}
//播放提示音
AudioServicesPlaySystemSound(m_reqfloorSoundID);我是用上面的方法播放提示音,但是为什么不能用iphone自带的调节音量来调节声音大小呢????