2014/10/15 下午 10:05:25

iphone Programming Glossary: concurrent

UITableView with images scrolls very slowly [duplicate]

http://stackoverflow.com/questions/12703297/uitableview-with-images-scrolls-very-slowly

asynchronous operations technologies . The former enjoys an advantage that you can specify precisely how many concurrent operations are permissible which is very important in loading images from the web because many web servers limit how many.. are permissible which is very important in loading images from the web because many web servers limit how many concurrent requests they will accept from a given client. The basic idea is Submit request of the image data in a separate background.. NSOperationQueue alloc init self.imageDownloadingQueue.maxConcurrentOperationCount 4 many servers limit how many concurrent requests they'll accept from a device so make sure to set this accordingly self.imageCache NSCache alloc init the rest of..

Difference between NSOperation and NSInvocationOperation?

http://stackoverflow.com/questions/12908886/difference-between-nsoperation-and-nsinvocationoperation

class to initiate an operation that consists of invoking a selector on a specified object. This class implements a non concurrent operation. 2.What is happening when we add NSOperation or NSInvocationOperation in NSoperationQueue You typically execute..

NSOperationQueue and concurrent vs non-concurrent

http://stackoverflow.com/questions/1646795/nsoperationqueue-and-concurrent-vs-non-concurrent

and concurrent vs non concurrent I want to setup a serialized task queue using NSOperationQueue but I'm a little confused by the terminology.. and concurrent vs non concurrent I want to setup a serialized task queue using NSOperationQueue but I'm a little confused by the terminology discussed in.. a little confused by the terminology discussed in the documentation. In the context of an NSOperation object the terms concurrent and non concurrent do not necessarily refer to the side by side execution of threads. Instead a non concurrent operation..

Subclassing NSOperation to be concurrent and cancellable

http://stackoverflow.com/questions/3859631/subclassing-nsoperation-to-be-concurrent-and-cancellable

NSOperation to be concurrent and cancellable I am unable to find good documentation about how to subclass NSOperation to be concurrent and also to support.. to be concurrent and cancellable I am unable to find good documentation about how to subclass NSOperation to be concurrent and also to support cancellation. I read the Apple docs but I am unable to find an official example. Here is my source code.. example I found I don't understand why performSelectorOnMainThread is used. It would prevent my operation from running concurrently. Also when I comment out that line I get my operations running concurrently. However the isCancelled flag is not modified..

Actual frequency of device motion updates lower than expected, but scales up with setting

http://stackoverflow.com/questions/5034411/actual-frequency-of-device-motion-updates-lower-than-expected-but-scales-up-wit

iphone cocoa touch intervals core motion share improve this question Okay here's a possible solution Number of concurrent operations on NSOperationQueue are determined by the OS. That means it sometimes can be very few or even 1 operation at..

What are the tradeoffs between performSelector:withObject:afterDelay: and dispatch_after

http://stackoverflow.com/questions/6205998/what-are-the-tradeoffs-between-performselectorwithobjectafterdelay-and-dispat

question dispatch_after is part of the new Grand Central Dispatch which is an extension to iOS aimed at improving concurrent code execution on multicore hardware. But overall I think they address different requirements overall. GCD allows to a much.. But overall I think they address different requirements overall. GCD allows to a much finer graded control over concurrent execution of code. You can schedule blocks on a queue remove them suspend resume etc. It is a broader topic to be considered..

AVPlayerItem fails with AVStatusFailed and error code “Cannot Decode”

http://stackoverflow.com/questions/8608570/avplayeritem-fails-with-avstatusfailed-and-error-code-cannot-decode

of my developer TSI lifelines to ask the question and I'll summarize the response. There is a limit on the number of concurrent video players that AVFoundation will allow. It is due to the limitations of iOS hardware. The limit for current devices..

Is UIGraphicsBeginImageContext thread safe?

http://stackoverflow.com/questions/11528803/is-uigraphicsbeginimagecontext-thread-safe

call this function from the main thread of your application only. However in the WWDC 2012 session video Building Concurrent User Interfaces the speaker shows that you can actually draw in the background and call that method in the background So..

How to achieve concurrent task through NSOperation? [closed]

http://stackoverflow.com/questions/12910479/how-to-achieve-concurrent-task-through-nsoperation

without NSoperationQueue Even if we use NSoperationQueue it will perform operations FIFO format.How will it execute Concurrently iphone ios ipad grand central dispatch nsthread share improve this question If you want to implement a concurrent.. the operation asynchronously without adding it to an operation queue. See the Concurrency Programming Guide section Concurrent Versus Non concurrent Operations Also Please read Managing Concurrency with NSOperation You typically execute operations..

Asynchronous methods in NSOperation

http://stackoverflow.com/questions/1596160/asynchronous-methods-in-nsoperation

nsoperation fbconnect share improve this question Dave Dribin describes how to do such thing in his blog post Concurrent Operations Demystified . His example shows async NSURLConnection but should be almost the same with FBConnect share improve..

What are block-based animation methods in iPhone OS 4.0?

http://stackoverflow.com/questions/3126833/what-are-block-based-animation-methods-in-iphone-os-4-0

Help with multi-threading on iOS?

http://stackoverflow.com/questions/4360591/help-with-multi-threading-on-ios

ios nsthread share improve this question The Concurrency Programming Guide by Apple is a nice reading. Concurrent programming is not something you might want to pick up by copying some sample code from the web and hacking until you are..

NSURLConnection and grand central dispatch

http://stackoverflow.com/questions/5037545/nsurlconnection-and-grand-central-dispatch

and recommended to use asynchronous network programming with RunLoop. Use background thread Grand Central Dispatch Concurrent Queue for thread safe data processing not for network programming. By the way Blocks and Grand Central Dispatch sessions.. data success dispatch_async dispatch_get_global_queue DISPATCH_QUEUE_PRIORITY_DEFAULT 0 ^ process downloaded data in Concurrent Queue dispatch_async dispatch_get_main_queue ^ update UI on Main Thread errorBlock ^ NSError error error share improve..