Thanks for the response. There is definitely a lot of goofiness in that code. I started from the apple xml performance demo, which had run-loop code that led me to believe that I had to run the NSURLConnection run loop in a thread. It's great that that's not the case (I re-read the example[1] and the only reason they have it is to do some blocking). I can drop all block use except the completion block, which should be a really nice cleanup.
I'll play around with the autorelease pool. The apple example had manual autorelease pool management during parsing. I'm going to just drop that entirely since I don't think my app is _that_ performance sensitive. The odd init-at-a-distance code was because I originally had the connection start upon init, which meant that I had a chicken and egg problem wrt initializing the handler (with a completion block that needed the connection) and the connection (which needed the handler). Now that start is manually run I can clean that up too. Thanks again, John [1] http://developer.apple.com/iphone/library/samplecode/XMLPerformance/Listings/Classes_LibXMLParser_m.html#//apple_ref/doc/uid/DTS40008094-Classes_LibXMLParser_m-DontLinkElementID_10 On Jun 21, 2010, at 10:48 AM, Kevin Wojniak wrote: > NSURLConnection already does its work asynchronously, there is no need to run > it on a separate thread. However if you still want to, you should use > [NSRunLoop currentRunLoop], which returns the run loop associated with that > thread. > > In your code you are not creating your objects properly. You should use the > form [[Class alloc] init] then operate on that object: > >> NSURLConnection *connection = [[NSURLConnection alloc] >> initWithRequest:urlRequest delegate:handler startImmediately:NO]; > > > Also I don't believe you need to create the autorelease pool. I think GCD > does it for you. > > Lastly, you should run the thread's run loop until your delegate method gets > called indicating the NSURLConnection is done. > > > > On Jun 20, 2010, at 1:42 PM, John Heitmann wrote: > >> >> On Feb 9, 2010, at 3:01 PM, Keith Duncan wrote: >> >>> ...you should create a 'concurrent' NSOperation as described in the >>> documentation, and schedule your NSURLConnection on +[NSRunLoop >>> mainRunLoop]. This will allow your NSOperation -start method to exit >>> immediately and the thread to return to the pool. >> >> I had a working async NSURLConnection scheme where I initialized the >> connection in a new thread and pumped its run loop manually on that thread >> until I saw the delegate set a completion flag. I thought I'd convert it to >> blocks since it cleans up some ugly code there. I'm 95% of the way there and >> things look good, but there are some lingering problems in my code that I >> don't understand. The above tip helped with one of my problems: the >> automatic block thread didn't pump the NSURLConnection run loop, so I >> scheduled the connection in the main run loop like Keith suggested and >> things worked. My first question is: doesn't this block the main loop with >> io? I have another version which uses a block to manually pump, but then >> this ties up an automatic block thread, which are supposed to be >> short-lived. Is it really a good practice to drive the NSURLConnection from >> the main loop? >> >> My second question is: How do I memory manage the autorelease pool that the >> delegate uses? Here's a rough idea of what I have now: >> >> dispatch_queue_t queue = >> dispatch_get_global_queue(DISPATCH_QUEUE_PRIORITY_DEFAULT, 0); >> dispatch_async(queue, ^{ >> __block NSAutoreleasePool *autoReleasePool = [[NSAutoreleasePool >> alloc] init]; >> NSURLConnection *connection = [NSURLConnection alloc]; >> ResponseHandler *handler = [ResponseHandler alloc]; >> >> [handler initWithDelegate:delegate >> completionBlock:^{dispatch_async(queue, ^{ >> [connection release]; >> [handler release]; >> [autoReleasePool release]; >> [delegate release]; >> });}]; >> >> [connection initWithRequest:urlRequest delegate:handler >> startImmediately:NO]; >> [connection scheduleInRunLoop:[NSRunLoop mainRunLoop] >> forMode:NSDefaultRunLoopMode]; >> [connection start]; >> }); >> >> ResponseHandler is pretty simple. It processes the data and calls the >> completionBlock when done. With that code I get "attempt to pop an unknown >> autorelease pool". When I drop the release altogether the error goes away, >> but that seems like a leak. >> >> John_______________________________________________ >> >> Cocoa-dev mailing list (Cocoa-dev@lists.apple.com) >> >> Please do not post admin requests or moderator comments to the list. >> Contact the moderators at cocoa-dev-admins(at)lists.apple.com >> >> Help/Unsubscribe/Update your Subscription: >> http://lists.apple.com/mailman/options/cocoa-dev/kainjow%40kainjow.com >> >> This email sent to kain...@kainjow.com > _______________________________________________ Cocoa-dev mailing list (Cocoa-dev@lists.apple.com) Please do not post admin requests or moderator comments to the list. Contact the moderators at cocoa-dev-admins(at)lists.apple.com Help/Unsubscribe/Update your Subscription: http://lists.apple.com/mailman/options/cocoa-dev/archive%40mail-archive.com This email sent to arch...@mail-archive.com
