Obj-C - Add activity indicator to pull down to refresh? - ios

Question

I've added a 'pull down to refresh' function to my TableView inside a ViewController. The data refresh works perfectly, but I'm wondering how I can add the classic activity indicator into the top when the refresh is executed?
ViewController.m
- (void)viewDidLoad {
[super viewDidLoad];
[_refreshControl addTarget:self action:#selector(refreshData) forControlEvents:UIControlEventValueChanged];
//[self.mytable addSubview:refreshControl];
UITableViewController *tableViewController = [[UITableViewController alloc] init];
tableViewController.tableView = self.tableView;
tableViewController.refreshControl = _refreshControl;
}
-(void)refreshData
{
UITableViewController *tableViewController = [[UITableViewController alloc] init];
tableViewController.tableView = self.tableView;
[self.tableView reloadData];
[tableViewController.refreshControl endRefreshing];
}

Answer 1

It looks like the issue is that both viewDidLoad and refreshData are creating new tableViewControllers but they should be updating your existing one.
If your class in ViewController.m is a subclass of UITableViewController you can update your code to use the current view controller.
- (void)viewDidLoad {
[super viewDidLoad];
[_refreshControl addTarget:self action:#selector(refreshData) forControlEvents:UIControlEventValueChanged];
self.refreshControl = _refreshControl;
}
-(void)refreshData
{
[self.tableView reloadData];
[self.refreshControl endRefreshing];
}
Another issue is that refreshData immediately calls endRefreshing so the refresh Controller wont have any time to be visible before it ends. Normally you'd have an asynchronous task running, like a network request, then call endRefreshing once that completes. To fake it you can delay calling endRefreshing with the following.
-(void)refreshData
{
// Wait 1 sec before ending refreshing for testing
dispatch_after(dispatch_time(DISPATCH_TIME_NOW, 1 * NSEC_PER_SEC), dispatch_get_main_queue(), ^{
[self.tableView reloadData];
[self.refreshControl endRefreshing];
});
}

Answer 2

This is what ended up working!
ViewController.h
#property (nonatomic, strong) UIRefreshControl *refreshControl;
ViewController.m
- (void)viewDidLoad {
[super viewDidLoad];
self.refreshControl = [[UIRefreshControl alloc] init];
self.refreshControl.attributedTitle = [[NSAttributedString alloc]initWithString:#"Pull To Refresh"];
[self.refreshControl addTarget:self action:#selector(refreshData) forControlEvents:UIControlEventValueChanged];
[self.tableView addSubview:self.refreshControl];
}
-(void)refreshData
{
// Wait 1 sec before ending refreshing for testing
dispatch_after(dispatch_time(DISPATCH_TIME_NOW, 1 * NSEC_PER_SEC), dispatch_get_main_queue(), ^{
[self.tableView reloadData];
[self.refreshControl endRefreshing];
});
}