Exporting templated class

Ok, I was able to reproduce the issue. TempHire uses the InterceptingCatalog from MefContrib and it looks like it is causing this issue. Unfortunately, the MefContrib project is dead, so this won't get fixed. If you want to use open generics, you gonna have to forgo the use of the InterceptingCatalog. I know of at least one other person who was having issues in their application because of the InterceptingCatalog. I will remove it from future versions in order to discourage its use.

At this point I'm at a loss as to what you are doing wrong. The example I gave you works just fine. You can download the entire solution from my Skydrive (http://sdrv.ms/VZ1pSj). If this doesn't work than I don't know. I also have two unit tests in the Cocktail test project to ensure open generics work and those tests pass. I can't spend more time on samples. You gonna have to hire one of our consultants to teach you MEF as so far there doesn't appear to be a bug in Cocktail's handling of open generics.

Edited by mgood - 22-Dec-2012 at 5:20pm

Here's a very silly example that works just fine for me. I'm not sure what's going on with your code. There's something you are not showing me. 

Cocktail 2.2.0

I looked at Cocktail sourse code(Test project) but not work
is still null

any other example to working ?


Edited by giotis - 21-Dec-2012 at 6:15pm

I tried by your example, to create generic ViewModel but failed

  [Export(typeof(GridViewViewModel<>))]
  public class GridViewViewModel<T> : Screen, IHandle<SavedMessage> where T : DomainModel.EntityBase    {

      ..... copy from StaffingResourceSearchViewModel

or with Interface

 public interface IGridView<T>   {
        void Start();
        T CurrentStaffingResource { get; set; }
        event System.ComponentModel.PropertyChangedEventHandler PropertyChanged;
    }

  [Export(typeof(IGridView<>))]
  public class GridViewViewModel<T> : Screen, IGridView<T>, IHandle<SavedMessage> where T :   DomainModel.EntityBase    {
  ....
 
            var viewModel= Composition.GetInstance<IGridView<DomainModel.StaffingResource>>();
            viewModel is null

            MEF don't create viewModels?

 In fact is possible?

thank you for your time

Hello,
I'm lost in a cave with Exporting with templates...

before I have had an interface of type IDashboard that has an ID (int) and a collection of Items of type Gauge

Now I've been asked if it's possible to define another type of Gauge and continue using existing code structure..so I've defined those class

[Export(typeof(IDashBoard<Gauge<ISnapshot>, ISnapshot>))]     public class DashboardViewModel : DashBoardBase<Indicatore<SNAPSHOT_INDICATORE_SELECT_Result>, SNAPSHOT_INDICATORE_SELECT_Result>     { ... }  public class DashBoardBase<T,Y> : Screen, IDashBoard<T, Y>         where T : GaugeBase<Y>         where Y : ISnapshot     { ... }  public class GaugeBase<T> : INotifyPropertyChanged where T:ISnapshot  { ... }  public interface ISnapshot     {         DateTime DT_TS { get; set; }     } public interface IDashBoard<T,Y> : INotifyPropertyChanged     where T : GaugeBase<Y>     where Y : ISnapshot {     BindableCollection<T> DataItems { get; set; }     T SelectedDataItem { get; set; }     int IdDashBoard { get; set; }     int IdLayout { get; } ... }

Before I had a dashboardfactory of type


        [ImportingConstructor]
        public DashBoardFactory()
        {
            //[ImportMany(typeof(IDashboard))] IEnumerable<IDashboard listaIndicatori
            this.listaIndicatori = listaIndicatori;
        }

and it was working... now I've tried all the ways but I'm not able to set the export so that my dashboardfactory can get items

   [ImportingConstructor]
        public DashBoardFactory()
        {
            //[ImportMany(typeof(DashBoardBase<GaugeBase<ISnapshot>, ISnapshot>))] IEnumerable<DashBoardBase<GaugeBase<ISnapshot>, ISnapshot>> listaIndicatori
            this.listaIndicatori = listaIndicatori;



            var items = Cocktail.Composition.GetInstances<IDashBoard<Indicatore<ISnapshot>, ISnapshot>>();
            int count = items.Count(); //0 or it says it cannot cast to type...
  
        }

Any suggestion?
Thanks