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    copied!<p>After reading @Greg's commented link and this other Q: <a href="https://stackoverflow.com/questions/11909629/waiting-until-two-async-blocks-are-executed-before-starting-another-block">Waiting until two async blocks are executed before starting another block</a></p> <p>I came up with this which is working the way I want:</p> <pre><code>-(void)refreshView:(UIRefreshControl *)refresh { dispatch_group_t group = dispatch_group_create(); __block BOOL isReachable = NO; __block NSData *data = nil; __block NSData *dataPublic = nil; dispatch_group_async(group,dispatch_get_global_queue(DISPATCH_QUEUE_PRIORITY_DEFAULT, 0), ^ { isReachable = [self.appDelegate isReachable]; }); dispatch_group_wait(group, DISPATCH_TIME_FOREVER); dispatch_group_async(group,dispatch_get_global_queue(DISPATCH_QUEUE_PRIORITY_DEFAULT, 0), ^ { if (isReachable) { data = [self fetchNewData]; } }); dispatch_group_async(group,dispatch_get_global_queue(DISPATCH_QUEUE_PRIORITY_DEFAULT, 0), ^ { if (isReachable) { dataPublic = [self fetchPublicData]; } }); dispatch_group_notify(group,dispatch_get_global_queue(DISPATCH_QUEUE_PRIORITY_DEFAULT, 0), ^ { if (isReachable) { dispatch_async(dispatch_get_main_queue(), ^{ //Public data if (dataPublic) { [self fetchedPublicData:dataPublic]; } else { //handle error } //User data if (data) { [self fetchedData:data]; [self.tableView reloadData]; } else { //handle error } [self.refreshControl endRefreshing]; }); } else { dispatch_async(dispatch_get_main_queue(), ^{ [self.refreshControl endRefreshing]; [self.appDelegate showConnectionErrorAlert]; }); } }); } </code></pre> <p>Please feel free to suggest improvements!</p>
 

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