在下面的电话中,我准备为我的应用程序中的四种不同声音准备一个AVAudioPlayer。如果我不这样做,它会导致应用程序延迟约1.5秒,因为我只是在需要听到它的地方这样做。因此,有什么方法可以使此代码看起来更好或更有效地工作,因为现在我已经在App-Delegate中准备好了这些声音,这会稍微降低启动速度。所以这是代码,让我知道是否有什么方法可以使下面的代码更好:
- (void)readySounds {
NSString *path = [[NSBundle mainBundle] pathForResource:@"TrackUno" ofType:@"mp3"];
NSURL *file = [[NSURL alloc] initFileURLWithPath:path];
AVAudioPlayer *one = [[AVAudioPlayer alloc] initWithContentsOfURL:file error:nil];
[file release];
self.tr1 = one;
[one release];
[tr1 prepareToPlay];
[tr1 setDelegate:self];
NSString *path2 = [[NSBundle mainBundle] pathForResource:@"TrackDos" ofType:@"mp3"];
NSURL *file2 = [[NSURL alloc] initFileURLWithPath:path2];
AVAudioPlayer *two = [[AVAudioPlayer alloc] initWithContentsOfURL:file2 error:nil];
[file2 release];
self.tr2 = two;
[two release];
[tr2 prepareToPlay];
[tr2 setDelegate:self];
NSString *path3 = [[NSBundle mainBundle] pathForResource:@"Click" ofType:@"mp3"];
NSURL *file3 = [[NSURL alloc] initFileURLWithPath:path3];
AVAudioPlayer *three = [[AVAudioPlayer alloc] initWithContentsOfURL:file3 error:nil];
[file3 release];
self.clk = three;
[three release];
[clk prepareToPlay];
[clk setDelegate:self];
NSString *path4 = [[NSBundle mainBundle] pathForResource:@"HSSound" ofType:@"mp3"];
NSURL *file4 = [[NSURL alloc] initFileURLWithPath:path4];
AVAudioPlayer *four = [[AVAudioPlayer alloc] initWithContentsOfURL:file4 error:nil];
[file4 release];
self.hs = four;
[four release];
[hs prepareToPlay];
[hs setDelegate:self];
}
最佳答案
如果您只关心初始化时间,那么您可以*在辅助线程上创建它,并改善感知的启动时间。然后它将初始化流和解码器,并从辅助线程从磁盘打开音频文件。
如果回放,流计数,内存使用,CPU,加载时间,解码,过滤,重采样等仍然是因素:您使用的是最高级别的API,则可以降低几个级别,并拥有对每个级别的所有控制权以及所有这些方面。
您可以通过重构使其看起来更好-该方法执行四次相似的序列。
*“可能”,因为我只使用了较低级别的API,所以我不知道AVAudioPlayer是否具有线程约束。
重构示例,其中添加了错误检查功能:
没有编译,但是您知道了:
- (AVAudioPlayer *)newAudioPlayerForFile:(NSString *)fileName extension:(NSString *)extension inBundle:(NSBundle *)bundle
{
assert(fileName && extension && bundle);
NSURL * url = [bundle URLForResource:fileName ofType:extension];
if (nil == url) {
assert(0 && "could not locate resource");
return nil;
}
NSError * error = 0;
AVAudioPlayer * spieler = [[AVAudioPlayer alloc] initWithContentsOfURL:url error:&error];
assert(spieler);
if (nil != error) {
NSLog(@"Error encountered creating audio player for file (%@): %@", fileName, error);
[spieler release], spieler = nil;
return nil;
}
[spieler prepareToPlay];
[spieler setDelegate:self];
return spieler;
}
- (void)readySounds
{
NSAutoreleasePool * pool = [NSAutoreleasePool new];
NSBundle * mainBundle = [NSBundle mainBundle];
self.tr1 = [[self newAudioPlayerForFile:@"TrackUno" extension:@"mp3" inBundle:mainBundle] autorelease];
self.tr2 = [[self newAudioPlayerForFile:@"TrackDos" extension:@"mp3" inBundle:mainBundle] autorelease];
self.clk = [[self newAudioPlayerForFile:@"Click" extension:@"mp3" inBundle:mainBundle] autorelease];
self.hs = [[self newAudioPlayerForFile:@"HSSound" extension:@"mp3" inBundle:mainBundle] autorelease];
[pool release], pool = nil;
}
关于iphone - 更有效的代码? (AVAudioPlayer),我们在Stack Overflow上找到一个类似的问题: https://stackoverflow.com/questions/7780025/