初始化系统声音服务(使用NSData)

Question

如何使用NsData初始化系统声音服务

NSString *pewPewPath = [[NSBundle mainBundle] 
pathForResource:@"pew-pew-lei" ofType:@"caf"];
NSURL *pewPewURL = [NSURL fileURLWithPath:pewPewPath];
AudioServicesCreateSystemSoundID((__bridge CFURLRef)pewPewURL, &self.pewPewSound);
AudioServicesPlaySystemSound(self.pewPewSound);

Answer 1

你需要在你的代码中做一个LOT的错误检查。

NSString *pewPewPath = [[NSBundle mainBundle] pathForResource:@"pew-pew-lei" ofType:@"caf"];
if(pewPewPath)
{
    CFURLRef pewPewURL = (CFURLRef)[NSURL fileURLWithPath:pewPewPath];
    if(pewPewURL)
    {
        OSStatus errorCode = AudioServicesCreateSystemSoundID(pewPewURL, &self.pewPewSound);
        if(errorCode)
        {
            NSLog(@"error in creating the system sound - %ld", errorCode);
        } else {
            AudioServicesPlaySystemSound(self.pewPewSound);
        }
    } else {
        NSLog(@"couldn't make pew-pew-lei into a URL");
    }
} else {
    NSLog( @"no pew-pew-lei.caf file found");
}