Where to databind a GridView?

Well,

The GridView is an implementation, Down the line if you decide to swap the GridView for a listview or something it should have no bearing on the data.

Exactly how to go about sharing the information is subjective. there is no right way.

My personal preference is a super contracted approach via interfaces. e.g:

public interface FooView
{
   IEnumberable<Foobar> Foobars { set; }

   FooPresenter Presenter { set; }

   void ShowView();
}


public interface FooPresenter
{
  void DisplayFoos();
  void StartApplication();

}

Now i imagine the above doesn't really give much detail but it outlines the vaguest contract between whatever visual representation you choose and the source of the data. In this manner if either change the other is perfectly fine.

As for an example implementation of the above:

    public class GridFooView : FooView
    {
      public FooPresenter Presenter { private get; set; }


      public IEnumerable<Foobar> Foobars
      {
        get{ return _foobars; }
        set
        {
          _foobars = value;
          UpdateFoobarGrid(); //Do binding here
        } 
      }


      void Button_ShowFoo_Clicked(object sender,Eventargs e)
      {
         Presenter.DisplayFoos();
      }


      private IEnumerable<Foobar> _foobars;
    }



public class FooPresenterImpl : FooPresenter
{

   FooView _view;

   public FooPresenterImpl(FooView view)
   {
     if(view == null) throw new NullArgumentException("view")
     _view = view;
     _view.Presenter = this;
   }


   void DisplayFoos()
   {
    //generate your data then pass it to the view who updates himself.
    // the example i have here includes another abstraction of a datamodel.
     _view.Foobars = someDataModel.GetFoos();
   }

   void StartApplication()
  {
    //Do prerequisites
    _view.ShowView(); 
  }


}

Now finally in your program run file you simple instantiate the Presenter of choice, with the view of choice and run startApplication().

FooPresenter presenter = new FooPresenterImpl(new GridFooView());
presenter.StartApplication();

So now if you decide to completely change how Foo's are delivered to the UI, replace the presenter but all views still work, want to make a different representation of the same data? make a new view object, finally your presenter could also contain a datamodel which could be swapped out between storage methods, different database's or config files or we service or whatever.