Problem with UITableViewDelegate

Question

Hi

I have the following tableviewdelegate:

private class TableViewDelegate : UITableViewDelegate
    {
        private DaysViewController _dvc;
        private List<DateTime> ConferenceDates;
        public TableViewDelegate (DaysViewController controller, List<DateTime> dates)
        {
            _dvc = controller;
            ConferenceDates = dates;
        }



        /// <summary>
        /// If there are subsections in the hierarchy, navigate to those
        /// ASSUMES there are _never_ Categories hanging off the root in the hierarchy
        /// </summary>
        public override void RowSelected (UITableView tableView, NSIndexPath indexPath)
        {
            string date = ConferenceDates[indexPath.Row].ToShortDateString ();
            Console.WriteLine ("DaysViewController:TableViewDelegate.RowSelected: Label=" + date);

                            /*SessionsViewController sessionsView = new SessionsViewController(date);
            sessionsView.Title = date;
            _dvc.NavigationController.PushViewController(sessionsView,true);*/



            EventsViewController eventsView = new EventsViewController (date);

            eventsView.Title = date;
            try {

                _dvc.NavigationController.PushViewController
                (eventsView, true);

            } catch (Exception ex) {
                Log.Error(ex);
            }
        }
    }

which gets added like so:

tableView = new UITableView { 
            Delegate = new TableViewDelegate (this, ConferenceDates), 
            DataSource = new TableViewDataSource (this, ConferenceDates), 
            AutoresizingMask = UIViewAutoresizing.FlexibleHeight | UIViewAutoresizing.FlexibleWidth, 
            BackgroundColor = UIColor.Clear, 
            TableHeaderView = navBar, 
            Frame = new RectangleF (0, 0, this.View.Frame.Width, this.View.Frame.Height) 
        };

It all works well for the UITableView - the data gets loaded etc but whenever I click on a cell to load the child data - _dvc.NavigationController is null

does anyone know where this gets set? or perhaps, if it's set by the framework - how it might get nulled?

cheers - let me know if i need to post more of the code.

w://

Answer 1

strange thing is - if i do this in the constructor:

public DVCTableViewDelegate (DaysViewController controller, List<DateTime> dates)
{
    this._dvc = controller;
    this.ConferenceDates = dates;
    this.navController = controller.NavigationController;
}

navController is a UINavigationController but dvc.NavigationController is null in the row selected method!

strangeness.

Answer 2

If you are going to use a navigation controller on a view, you can accomplish this by creating an instance of a UINavigationController and add your view to this controller. Then your view becomes a sub view of the UINavigationController and your view´s NavigationController should now be accessible from within your TableViewDelegate. Present the Navigation controller the you want. In the example below, as a modal view controller.

tableView = new UITableView { 
            Delegate = new TableViewDelegate (this, ConferenceDates), 
            DataSource = new TableViewDataSource (this, ConferenceDates), 
            AutoresizingMask = UIViewAutoresizing.FlexibleHeight | UIViewAutoresizing.FlexibleWidth, 
            BackgroundColor = UIColor.Clear, 
            TableHeaderView = navBar, 
            Frame = new RectangleF (0, 0, this.View.Frame.Width, this.View.Frame.Height) 
        };

UINavigationController navController = new UINavigationController(tableView);
navController.ModalTransitionStyle = UIModalTransitionStyle.FlipHorizontal;

this.PresentModalViewController(navController, true);