rhult

- (void)viewDidLoad
{
    [super viewDidLoad];

    // If UITableViewController, otherwise comment out (make sure to name your tableview ivar tableView if so).
    self.clearsSelectionOnViewWillAppear = NO;
}

// Use the workaround:
- (void)viewDidAppear:(BOOL)animated

rhult

// Using the workaround in a UITableViewController:

// If UITableViewController, do this in viewDidLoad:
//    self.clearsSelectionOnViewWillAppear = NO;

// Then add:
//- (void)viewDidAppear:(BOOL)animated
//{
//    [super viewDidAppear:animated];
//    [self deselectWorkaroundForSelector:_cmd];

rhult

extension String {
    func toDouble() -> Double? {
        var formatter = NSNumberFormatter()
        let number = formatter.numberFromString(self)
        if number == nil {
            return nil
        }
        return number.doubleValue
    }
}