AFNetworking cancel downloading - objective-c

Question

I am using AFNetworking framework. So I created subclass of the AFHTTPClient:
+ (MyNetClient *)sharedClient
{
static MyNetClient *_sharedClient = nil;
static dispatch_once_t oncePredicate;
dispatch_once(&oncePredicate, ^{
_sharedClient = [[self alloc] initWithBaseURL:[NSURL URLWithString:BASE_API_URL]];
});
return _sharedClient;
}
And added some methods for downloading JSON from the server.
So In my view, I start download in viewWillAppear like this:
[[MyNetClient sharedClient] getArrOfDataWithName:name
block:^(NSArray *arr) {
}];
Where:
- (void)getArrOfDataWithName:(NSString *)name block:^(NSArray *arr)block
{
dispatch_async(dispatch_get_global_queue(DISPATCH_QUEUE_PRIORITY_DEFAULT, 0), ^{
NSMutableDictionary *params = [NSMutableDictionary
dictionaryWithObjectsAndKeys:name,#"name",nil];
[self getPath:[self urlToService:#"data/get.json"] parameters:params
success:^(AFHTTPRequestOperation *operation, id responseObject) {
NSLog(#"result operation%#",operation);
BOOL res = [operation isCancelled];
if (!res)
{
dispatch_async(dispatch_get_main_queue(), ^{
block(responseObject);
});
}
}
failure:^(AFHTTPRequestOperation *operation, NSError *error) {
dispatch_async(dispatch_get_main_queue(), ^{
block(nil);
});
}];
});
}
It takes more time and user can press back, so I cancel downloading in viewDidDisappear:
- (void)viewDidDisappear:(BOOL)animated
{
[super viewDidDisappear:animated];
[[[LRLoopNetClient sharedClient] operationQueue] cancelAllOperations];
}
But downloading operation not canceled. I added breakpoint to getArrOfDataWithName in line:
NSLog(#"result operation%#",operation);
BOOL res = [operation isCancelled];
res = NO and It is called after I leave view. I checked that:
NSInteger count = [[[LRLoopNetClient sharedClient] operationQueue] operationCount];
NSLog(#"number operations: %i",count);
In viewDidDisappear number operations:0
Please help me to cancel downloading.