AFNetwork download Progress

gistfile1.m

[op setDownloadProgressBlock:^(NSInteger bytesRead, long long totalBytesRead, long long totalBytesExpectedToRead) {
        if (totalBytesExpectedToRead > 0) {
            dispatch_async(dispatch_get_main_queue(), ^{
                self.progressView.alpha = 1;
                self.progressView.progress = (float)totalBytesRead / (float)totalBytesExpectedToRead;
                NSString *label = [NSString stringWithFormat:@"Downloaded %lld of %lld bytes", 
                                   totalBytesRead,
                                   totalBytesExpectedToRead];
                self.progressLabel.text = label;
            });
        }
    }];