UIActivityIndicatorView *activityIndicator = [[UIActivityIndicatorView alloc] initWithActivityIndicatorStyle:UIActivityIndicatorViewStyleGray];
[activityIndicator setCenter:self.tableView.center]; // to center on tableview
activityIndicator.frame = CGRectMake(self.tableView.center.x-10, self.tableView.center.y-40, 30, 30); // to determine the center
[activityIndicator setHidden:FALSE];
[activityIndicator startAnimating];
[self.view addSubview:activityIndicator];
[self.view bringSubviewToFront:activityIndicator];

activityIndicator

iphone

Objective C