nsoperationqueue

问题 i use a combination of queue and resultscontroller to update and display some coredata objects. in my uitableviewcontroller i call every X second a method in my main controller object. [NSTimer scheduledTimerWithTimeInterval:2 target:self selector:@selector(test:) userInfo:nil repeats:YES]; } - (void)test:(NSTimer*)theTimer { [[MainController instance] updatePersons]; } In this method a custom NSOperation object will be added to my main Q. - (BOOL)updatePersons { UpdatePersonsOperation* u = [

问题 I'm after some advice on the use of NSOperation and drawing: I have a main thread create my NSOperation subclass, which then adds it to an NSOperationQueue . My NSOperation does some heavy processing, it is intended to loop in its main() method for several minutes, constantly processing some work, but for now I just have a while() loop with a sleep(1) inside, which is set to go around just 5 times (for testing). The main (original) thread which spawns this NSOperation is responsible for

问题 I am developing an app that requires a completion block and a "barrier" functionality. As far as I know, NSOperation API has a completionBlock property and GCD API has the dispatch_barrier_(a)sync function to handle the barrier needs. What should I do in order to accomplish both of the needs? Thanks! 回答1: dispatch_group should have all the pieces you need. Just dispatch_group_async/dispatch_group_enter for your work units, then dispatch_group_notify for your completion handler. 来源： https:/

问题 This question already has answers here : Default value of maxConcurrentOperationCount for NSOperationQueue (2 answers) Closed 4 years ago . It is always being asked in interview how many maximum threads we can run in ios iphone programming simultaneously in NSOperationQueue and through GCD async? Please explain the answer. 回答1: You should be using NSOperationQueueDefaultMaxConcurrentOperationCount when you create your operations to let the OS decide the maximum number of operations - it will

问题 I have a basic question as to how the order of operations goes inside NSOperationQueue addOperationsWithBlock . What I want to do: [_queue addOperationWithBlock:^{ //starts a new thread to download an image //returns a response from the server if (returnResponse != nil) { //what I need to accomplish: //1) Update the collectionViewCell with data //2) Cache the image locally //3) Save the image name in local database } }]; I don't need the code to do this, I just need to know how it works. For

问题 I have a basic question as to how the order of operations goes inside NSOperationQueue addOperationsWithBlock . What I want to do: [_queue addOperationWithBlock:^{ //starts a new thread to download an image //returns a response from the server if (returnResponse != nil) { //what I need to accomplish: //1) Update the collectionViewCell with data //2) Cache the image locally //3) Save the image name in local database } }]; I don't need the code to do this, I just need to know how it works. For

问题 i have the following code to make requests to my api: -(void)makeApiCall:(NSString *)function params:(NSDictionary *)params notificationName:(NSString *)notificationName { NSURL *url = [NSURL URLWithString:kBaseUrl]; AFHTTPClient *httpClient = [[AFHTTPClient alloc] initWithBaseURL:url]; httpClient.parameterEncoding = AFFormURLParameterEncoding; NSMutableURLRequest *request = [httpClient requestWithMethod:@"POST" path:[NSString stringWithFormat:@"%@/%@",kApiBaseUrl,function] parameters:params]

问题 I am trying to measure time taken per GET request when downloading a file using AFNetworking. I am downloading a file repeatedly in a loop. The problem I am having is that the way I am measuring total time, it gives a much larger total time than it actually is. For example, for 50 downloads it gives 72 sec but in reality it only took around 5 sec. I also suspect 5 sec is too low for 50 downloads(the download size is 581 kb per file). How do I effectively measure time in this case? I need time

问题 I m new to iphone. where i get examples for NSOperationQueue , NSOperation ? What is the advantage of NSOperationQueue , NSOperation over thread? Thanks 回答1: Read the docs. They are really good at explaining and giving examples http://developer.apple.com/library/ios/#documentation/General/Conceptual/ConcurrencyProgrammingGuide/OperationObjects/OperationObjects.html%23//apple_ref/doc/uid/TP40008091-CH101-SW1 NSOperation is easier to manage than NSThread. 回答2: Higher level of abstraction: That

问题 I want to add images in array in sequence after downloading. I am appending images in array after downloading one by one but they are not in sequence. Can any one please tell me what is best way to do this. var queue: NSOperationQueue = { let _queue = NSOperationQueue() _queue.maxConcurrentOperationCount = 4 return _queue }() var imageArrayNsData : [NSData] = [] let session = NSURLSession.sharedSession() @IBAction func didClickOnStart(sender: AnyObject) { queue.cancelAllOperations() let