播放NSSound两次

Question

我想播放两次NSSound，除了它不到10秒，然后我想等到10秒完成，然后开始第二次。

但是我已经在两次播放同一个NSSound时遇到了问题。

NSString *resourcePath = [[NSBundle mainBundle] pathForResource:@"MessageArrived" ofType:@"wav"];
NSSound *sound = [[NSSound alloc] initWithContentsOfFile:resourcePath byReference:YES];
[sound play] //It plays the fist time
[sound play] //I get the following Error and it doesn't play a secont time
/*malloc: *** auto malloc[498]: error: GC operation on unregistered thread. Thread registered implicitly. Break on auto_zone_thread_registration_error() to debug.*/

谁能告诉我这个错误的原因是什么？我该怎么处理呢？

有没有其他方法可以让我这样做呢？

Answer 1

因此，经过大量的搜索和尝试修复它，我找到了我问题的解决方案……

NSSound *sound = [NSSound soundNamed:@"MessageArrived"];
BOOL res = [sound play];
NSLog(@"%d", res);
[NSThread detachNewThreadSelector:@selector(playSecondSound:) toTarget:self withObject:sound];

-(void)playSecondSound:(NSSound*)sound
{
    [NSThread sleepForTimeInterval:10-[sound duration]];
    [sound stop];
    BOOL res = [sound play];
    NSLog(@"%d", res);
}

我发现，即使在声音结束时，我也必须在启动第二个声音之前调用sound stop。

Answer 2

当你调用第二个play方法时，声音已经在播放了，显然是垃圾收集中的一个bug，因为第二个play应该被忽略，但这不是你想要实现的问题。

NSString *resourcePath = [[NSBundle mainBundle] pathForResource:@"MessageArrived" ofType:@"wav"];
NSSound *sound = [[NSSound alloc] initWithContentsOfFile:resourcePath byReference:YES];
[sound play];

//Will play the second time after 10.0 seconds have passed.
NSInteger wait = ([sound duration] < 10.0) ? 10.0 - [sound duration] : 0.0; 
[sound performSelector:@selector(play) withObject:nil afterDelay:wait];