Iphone 立即停止音乐
嗨,我有一个应用程序,你必须按住一个按钮,吹进手机,它会发出声音,下面是代码:Iphone 立即停止音乐,iphone,objective-c,ios,xcode,avfoundation,Iphone,Objective C,Ios,Xcode,Avfoundation,嗨,我有一个应用程序,你必须按住一个按钮,吹进手机,它会发出声音,下面是代码: #import "AirInstrumentViewController.h" @implementation AirInstrumentViewController @synthesize audiOfA; - (void)didReceiveMemoryWarning { / / Releases the view if it doesn't have a supe
#import "AirInstrumentViewController.h"
@implementation AirInstrumentViewController
@synthesize audiOfA;
- (void)didReceiveMemoryWarning
{
/ / Releases the view if it doesn't have a superview.
[super didReceiveMemoryWarning];
// Release any cached data, images, etc that aren't in use.
}
#pragma mark - View lifecycle
- (void)viewDidLoad
{
[super viewDidLoad];
NSURL *url = [NSURL fileURLWithPath:@"/dev/null"];
NSDictionary *settings = [NSDictionary dictionaryWithObjectsAndKeys:
[NSNumber numberWithFloat: 44100.0], AVSampleRateKey,
[NSNumber numberWithInt: kAudioFormatAppleLossless], AVFormatIDKey,
[NSNumber numberWithInt: 1], AVNumberOfChannelsKey,
[NSNumber numberWithInt: AVAudioQualityMax], AVEncoderAudioQualityKey,
nil];
NSError *error;
recorder = [[AVAudioRecorder alloc] initWithURL:url settings:settings error:&error];
if (recorder) {
[recorder prepareToRecord];
recorder.meteringEnabled = YES;
[recorder record];
levelTimer = [NSTimer scheduledTimerWithTimeInterval: 0.03 target: self selector: @selector(levelTimerCallback:) userInfo: nil repeats: YES];
} else
NSLog([error description]);
}
- (void)levelTimerCallback:(NSTimer *)timer {
[recorder updateMeters];
const double ALPHA = 0.05;
double peakPowerForChannel = pow(10, (0.05 * [recorder peakPowerForChannel:0]));
lowPassResults = ALPHA * peakPowerForChannel + (1.0 - ALPHA) * lowPassResults;
if (lowPassResults > 0.55) {
NSLog(@"Mic blow detected");
if (aIsBeingTouched == YES) {
NSString *musicString = [[NSBundle mainBundle] pathForResource:@"A" ofType:@"aifc"];
audiOfA = [[AVAudioPlayer alloc] initWithContentsOfURL:[NSURL fileURLWithPath:musicString] error:NULL];
[audiOfA play];
} }else {
[audiOfA stop];
}
}
-(void)touchesBegan:(NSSet *)touches withEvent:(UIEvent *)event {
UITouch *touch = [[event allTouches] anyObject];
CGPoint touchLocation = [touch locationInView:self.view];
if (CGRectContainsPoint(aImage.frame, touchLocation)) {
aImage.image = [UIImage imageNamed:@"active.png"];
aIsBeingTouched = YES;
}
}
-(void)touchesEnded:(NSSet *)touches withEvent:(UIEvent *)event {
[audiOfA stop];
aImage.image = [UIImage imageNamed:@"a.png"];
aIsBeingTouched = NO;
}
- (void)viewDidUnload
{
[super viewDidUnload];
// Release any retained subviews of the main view.
// e.g. self.myOutlet = nil;
}
@end
我希望你明白我想做什么。在这里:
如果(lowPassResults>0.55){
NSLog(“检测到话筒冲击”)
声音持续一段时间,然后停止。触碰结束时也是如此。如果我吹
当我没有按下图像时,当我最终按下图像时,它会播放,即使我没有吹,因为我在没有按下图像时吹了,它可能已经录制了它或其他东西!我不知道如何解决所有这些问题,请帮助!
NSTimer
非常不可靠。根据,引用:
计时器时间间隔的有效分辨率限制为50-100毫秒
可能是因为您调用它们的速度太快(0.03秒或30毫秒相当快),NSTimer
没有按精确的间隔被调用,因此它正在跳过
您可能希望尝试多线程处理,以便与UI
相关的所有操作都在主线程上完成,AVAudio
部分在单独的线程上完成。这是一个解释NSOperation
的链接,这是一种简单的方法,并且在您提供的代码中应该可以很好地完成
希望这能有所帮助!我不明白这个链接如何能帮助我真正的音乐停止,就像一秒钟后的想法一样,因为你可以对
AVAudio
部分使用NSOperation
,这样这个过程就可以在一个单独的线程上完成,从而加快主线程的速度,并改善所有NSTimer
,以及触摸事件和其他UI元素。你能给我代码和解释吗?我看了参考资料,但我无法理解,对不起
if (aIsBeingTouched == YES) {
NSString *musicString = [[NSBundle mainBundle] pathForResource:@"A" ofType:@"aifc"];
audiOfA = [[AVAudioPlayer alloc] initWithContentsOfURL:[NSURL fileURLWithPath:musicString] error:NULL];
[audiOfA play];
} }else {
[audiOfA stop];
}
}