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| iOS 私有库怎么用 Carthage 集成呢？ iDev • EdwardEan • 2016-08-03 11:48:28 AM |
EdwardEan 最近回复了
2016-04-12 14:29:43 +08:00 回复了 Dean 创建的主题 › iDev › iOS GCD 线程死锁的疑问 |
接上一段回复内容：
dispatch_sync(dispatch_get_global_queue(0, 0), ^{
[[NSOperationQueue mainQueue] addOperationWithBlock:^{
NSLog(@"First");
}];
[[NSOperationQueue currentQueue] addOperationWithBlock:^{
NSLog(@"Three");
}];
__block id observer = [[NSNotificationCenter defaultCenter] addObserverForName:@"MyNotif" object:nil queue:[NSOperationQueue mainQueue] usingBlock:^(NSNotification *note) {
NSLog(@"Receive Notif");
[[NSNotificationCenter defaultCenter] removeObserver:observer];
}];
[[NSOperationQueue currentQueue] addOperationWithBlock:^{
NSLog(@"Forth");
}];
[[NSNotificationCenter defaultCenter] postNotificationName:@"MyNotif" object:self];
[[NSOperationQueue currentQueue] addOperationWithBlock:^{
NSLog(@"Five");
}];
});
dispatch_sync(dispatch_get_global_queue(0, 0), ^{
[[NSOperationQueue mainQueue] addOperationWithBlock:^{
NSLog(@"First");
}];
[[NSOperationQueue currentQueue] addOperationWithBlock:^{
NSLog(@"Three");
}];
__block id observer = [[NSNotificationCenter defaultCenter] addObserverForName:@"MyNotif" object:nil queue:[NSOperationQueue mainQueue] usingBlock:^(NSNotification *note) {
NSLog(@"Receive Notif");
[[NSNotificationCenter defaultCenter] removeObserver:observer];
}];
[[NSOperationQueue currentQueue] addOperationWithBlock:^{
NSLog(@"Forth");
}];
[[NSNotificationCenter defaultCenter] postNotificationName:@"MyNotif" object:self];
[[NSOperationQueue currentQueue] addOperationWithBlock:^{
NSLog(@"Five");
}];
});
2016-04-12 14:28:51 +08:00 回复了 Dean 创建的主题 › iDev › iOS GCD 线程死锁的疑问 |
不知道题主有没有读过 dispatch_sync 方法的这一段注释：
As an optimization, dispatch_sync() invokes the block on the current thread when possible.
如果明白了请试着考虑下下面一段代码的输出结果：
As an optimization, dispatch_sync() invokes the block on the current thread when possible.
如果明白了请试着考虑下下面一段代码的输出结果：
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