?????????I/O?????У??????????????????????????Щ??????????д????????????????????硣

??????????????????????NSURLConnection?????·?????????????????У?

????+ (void)sendAsynchronousRequest:(NSURLRequest *)request queue:(NSOperationQueue *)queue completionHandler:(void (^)(NSURLResponse*?? NSData*?? NSError*))handler

????????????????????????AFNetworking??

???????????????Щ??????????????????(???????????????????????????????ж?д)????????GCD(Grand Central Dispatch)????NSOperations ?? NSOperationQueues??

?????????????????GCD???????壺

????dispatch_async(dispatch_get_global_queue(DISPATCH_QUEUE_PRIORITY_DEFAULT?? 0)?? ^{ // switch to a background thread and perform your expensive operation dispatch_async(dispatch_get_main_queue()?? ^{ // switch back to the main thread to update your UI });});

????????????????????dispatch_async???滹????????dispatch_async??????????????UIKit???????????????????????С?

??????NSOperation??GCD?е???????????????Ray Wenderlich?е????iOS?ж?????GCD—?????????Soheil Azarpour????????NSOperations??NSOperationQueues????

????6) ???????С??UIImageView???

???????????UIImageView??С???

????????????????bundle?е????????UIImageView?У??????????UIImageView???С???????????????????????????????????UIImageView???UIScrollView?С?

????????????????????????????????????????????磬??????????????????????????????????????????????????????????????????????????????——???????????????!——???????UIImageView????????????????

????7) ???????????

???????????????

??????????????????????д??Ч??????????????????????????????????????

?????????????????????£???????????(Collections Programming Topics)——????????????????????п???????????????????????????????ü?????????????????????????????????

????????????????(TLDR)????????????????????????飺

???????飺??????????????е?????б?????????????????????????????????в????????????????????????????

???????: ?洢??/????????????????????

????Sets: ?????????????е??б??????????????????????????????????

????8) ???GZIP???

???????GZIP???

?????????????????????????????Щ???????????????????????????????APIs??????????????????????????????Щ???????Щ?????????XML??JSON??HTML?????????Щ????????

????????????????豸??????????????????????豸??????EDGE????????????????????3G?????С?????????????£????????????????

????????????????????????GZIP?????紫???е??????????????????????С??????С???????????????????????????????????????????????к?????????

????iOS?У???????NSURLConnection???????????????????GZIP?????????????NSURLConnection????????GZIP???????AFNetworking????????Щ?????????????????????????????????????? Google App Engine??

????????????????GZIP??????????£????????????Apache??IIS???????п??????GZIP?????

?????????????http://betterexplained.com/articles/how-to-optimize-your-site-with-gzip-compression/