Is there an iOS override for when a view was popped back?

Question

I have a MasterDetail Application, and a NavButton to add a new item. Im am able to successfully pop the view back, however I need to reload the table nice that is done. So how exactly can my MasterViewController know when it was popped so it could reload?

Heres the Pop code:

NavigationController.PopViewController(true);

It functions as expected, I just then need MasterViewController to reload the table, which I made a method for:

public void ReloadTable()
{
    TableView.ReloadData ();
}

Answer 1

Try this:

public partial class MasterViewController : UIViewController
{
    public void ReloadTable()
    {
        TableView.ReloadData ();
    }
}



public partial class DetailViewController : UIViewController
{
    public override void ViewWillDisappear (bool animated)
    {
        var masterViewController = NavigationController.ViewControllers.OfType<MasterViewController> ().FirstOrDefault();
        if (masterViewController != null) {
            masterViewController.ReloadTable ();
        }

        base.ViewWillDisappear (animated);
    }
}

You need to add using System.Linq; to get the OfType method.

Answer 2

Objective-C

It can be done by checking if navigationController contains viewcontroller like this:

Note viewControllerA pushes viewControllerB

Now in viewControllerB use viewWillDisappear method

- (void)viewWillDisappear:(BOOL)animated
{
  if (![[self.navigationController viewControllers] containsObject: self]) //any other hierarchy compare if it contains self or not
  { 
    // the view has been removed from the navigation stack or hierarchy, back is probably the cause
    // this will be slow with a large stack however.

    viewControllerA *objViewControllerA = [[self.navigationController viewControllers] lastObject];
    //NSLog(@"%@",objViewControllerA);
    if (objViewControllerA)
    {
        [objViewControllerA viewPoppedBack];
    }
  }
}

Now add one method in viewControllerA

 -(void)viewPoppedBack
 {
    //reload tableview here
    [yourTableViewHere reloadData];
 }