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POiOS - NJSONSerialization causing a memory leak??(according to Instruments)
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copied!<p>Below is the method with the code, where I am getting a memory leak using manual memory management. The memory leak is detected by using Xcode instruments and specifically points to the line where I am using NSJSONSerialization. I am running the target app (on a device with iOS 6.1). </p> <p>The first time that i tap on the refreshButton there is no leak. Any subsequent tap generates the leak(and more leaks on top of that if i continue tapping the button). Below is the code - This is basic stuff for consuming JSON web services(the web service link is bogus but the real one that I am using works). You will notice that I am using Grand Central Dispatch so that I can update the UI without waiting for the parsing of the JSON to finish. </p> <p>The line detected by instruments is surrounded by the asterisks. I would like to get some help to anyone who might have an idea of what is going on here. The full stack trace(as mentioned in the below comments i will put here:)</p> <blockquote> <p>+(NSJSONSerialization JSONObjectWithData:option:error:] -> -[_NSJSONReader parseData:options:] -> -[_NSJSONReader parseUTF8JSONData:skipBytes:options]->newJSONValue->newJSONString->[NSPlaceholde‌rString initWithBytes:length:encoding:]</p> </blockquote> <pre><code>-(void)parseDictionary:(NSDictionary *)dictonary{ self.transactions = [dictonary objectForKey:@"transactions"]; if(!self.transactions){ NSLog(@"Expected 'transactions' array"); return; } for (int arrayIndex = 0; arrayIndex < [self.transactions count]; arrayIndex++) { TransactionResult *result = [[[TransactionResult alloc] init] autorelease]; result.transactionID = [[self.transactions objectAtIndex:arrayIndex] objectForKey:@"ID"]; result.transactionDescription = [[self.transactions objectAtIndex:arrayIndex] objectForKey:@"description"]; result.transactionPrice = [[self.transactions objectAtIndex:arrayIndex] objectForKey:@"price"]; self.totalPrice += [result.transactionPrice doubleValue]; NSLog(@"total price: %f", self.totalPrice); [self.transactionResults addObject:result]; result = nil; } </code></pre> <p>}</p> <pre><code> - (IBAction)refreshButtonPressed:(UIBarButtonItem *)sender { __block id resultObject; dispatch_async(dispatch_get_global_queue(DISPATCH_QUEUE_PRIORITY_DEFAULT, 0),^{ NSURL *url = [NSURL URLWithString:@"http://mywebservice.php"]; NSData *data = [NSData dataWithContentsOfURL:url]; NSError *error; ***resultObject = [NSJSONSerialization JSONObjectWithData:data options:NSJSONReadingAllowFragments error:&error];*** if(!error){ if([resultObject isKindOfClass:[NSDictionary class]]){ NSDictionary *dictonary = resultObject; [self parseDictionary:dictonary]; NSLog(@"Done parsing!"); dispatch_async(dispatch_get_main_queue(), ^{ self.isLoading = NO; [self.transactionsTableView reloadData]; }); } else{ NSLog(@"JSON Error: Expected Dictionary"); resultObject = nil; return; } } else{ NSLog(@"JSON Error: %@", [error localizedDescription]); dispatch_async(dispatch_get_main_queue(), ^{ resultObject = nil; [self.transactionsTableView reloadData]; [self showError]; }); return; } }); } </code></pre>

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