nsoperation

I need to pause a running NSOperation which was inserted in an NSOperationQueue. Currently I am canceling all operations and restarting them. But this would lead to some kind of duplication in terms of process done. I tried with setSuspended flag of NSOperationQueue. But it's not suspending the operation. Is there any way out? brush51 see this: Link And here from the apple docs : Suspending and Resuming Queues If you want to issue a temporary halt to the execution of operations, you can suspend the corresponding operation queue using the setSuspended: method. Suspending a queue does not cause

I'm currently working with an NSPersistentDocument subclass that uses NSOperation to import data in the background. As per the documentation, I'm observing the NSManagedObjectContextDidSaveNotification after saving in the background task and propagating the notification to the NSManagedObjectContext in the main thread using -mergeChangesFromContextDidSaveNotification: . Everything works fine, but it presents a weird workflow for a user who's importing data into a new document. They need to save an empty document before doing the import (otherwise the -save: fails because the document hasn't

I have NSOperationQueue with some NSOperations in it ( NSInvocationOperations , in particular). This operations do some calculations and change states of UI elements accordingly (of course, via performSelectorOnMainThread:... ), often with use of animations. My UI has UINavigationViewController and some buttons for navigation to another views. So user can leave current view, while calculations / animations are still in progress. And what I need is to stop this somehow until user comes back to current view. The only solution I found is to create some thread-safe boolean flag - and to check it

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 drawing to a view and updating the UI. I intended to have the NSOperation thread use a notification to tell

I am implementing an iOS App that needs to fetch a huge amount of images over HTTP. I've tried several approaches but independently what I do, Instuments shows constantly increasing memory allocations and the App crashes sooner or later when I run it on a device. There are no leaks shown by Instruments. So far I have tried the following approches: Fetch the images using a synchronous NSURLConnection within an NSOperation Fetch the images using a asynchronous NSURLConnection within an NSOperation Fetch the images using [NSData dataWithContentsOfURL:url] in the Main-Thread Fetch the images using