nslock

一、使用 synchronized 方式 // 线程 1 dispatch_async ( dispatch_get_global_queue ( DISPATCH_QUEUE_PRIORITY_DEFAULT , 0 ), ^{ @synchronized ( _myLockObj ){ [obj1 method1 ]; sleep ( 30 ); } @synchronized (obj1){ } }); // 线程 2 dispatch_async ( dispatch_get_global_queue ( DISPATCH_QUEUE_PRIORITY_DEFAULT , 0 ), ^{ sleep ( 1 ); @synchronized ( _myLockObj ){ [obj1 method2 ]; } }); } 这样，就会起到锁的作用，线程2会等待线程1执行完成 @synchronized (obj){ }块后，在执行。从而起到锁的作用。 2.使用 NSLock 方式 先贴一个例子： 1. TestObj.h @interface TestObj : NSObject - ( void )method1; - ( void )method2; @end 2. TestObj.m #import "TestObj.h" @implementation TestObj

I current have a set of asynchronous functions that are both called in the viewDidLoad() . At the end of each function is a bool that is set from false to true upon completion of the function. There is also a conditional statement checking both function's bools that fires a third function. This conditional statement is in both functions (that I want called when both of the two have finished). Generally: var checkOne = false var checkTwo = false func functionOne(){ //async stuff checkOne = true if checkOne == true && checkTwo == true{ functionThree()//will only run if both functionOne and

I have a property @property NSLock *myLock And I want to write two methods: - (void) lock and - (void) unlock These methods lock and unlock myLock respectively and they need to do this regardless of what thread or queue called them. For instance, thread A might have called lock but queue B might be the one calling unlock . Both of these methods should work appropriately without reporting that I am trying to unlock a lock from a different thread/queue that locked it. Additionally, they need to do this synchronously. It is rare anymore that NSLock is the right tool for the job. There much better

I have my main application delegate which contains a method that returns an object. This application delegate runs on the main thread. I also have a NSOperation that gets run on a different thread. As well as wanting to be able to call my app delegate method on my main thread sometimes, I also need to call it from my NSOperation thread to get the object that it returns. My first question is, if I call this from my other thread... id newObject = [[[UIApplication sharedApplication] delegate] myMethod]; ... will that method be processed on the same thread as the NSOperation, or will it be the

I have recently, like a few people, discovered that [ALAssetsLibrary enumerateGroupsWithTypes] likes to run its blocks on another thread. What a shame that Apple didn't document that :-) In my current circumstance I need to wait for the enumeration to complete, before the main thread returns any results. I clearly need some sort of thread synchronisation. I've read about NSLock & NSConditionLock, but nothing yet seems to fit the requirement of 'signal a blocked thread that this worker thread has completed'. It seems like a simple enough need - can anyone point me in the right direction? Your