Cast a class belonging to a dll loaded dynamically to an abstract class belonging to another dll

Question

i have a problem to cast ViewModel Class with abstract class from external assembly.

i have 2 dlls and one executable:

one Abstract class into dll Cockpit.RUN.Common.dll, this Dll is referenced: in the other project of dll Cockpit.RUN.ViewModels and in the project of executable Cockpit.RUN.Test, but Cocpit.RUN.ViewModels is not referenced in the project of executable, because its loaded dynamically

The abstrac class: (dll)

using Caliburn.Micro;

namespace Cockpit.RUN.Common
{
    public abstract class PluginModel : PropertyChangedBase
    {
        public abstract double Width { get; set; }
        public abstract double Height { get; set; }
        public abstract double Left { get; set; }
        public abstract double Top { get; set; }

        private double zoomfactorfrompluginmodel;
        public double ZoomFactorFromPluginModel
        {
            get => zoomfactorfrompluginmodel;
            set
            {
                zoomfactorfrompluginmodel = value;
                NotifyOfPropertyChange(() => ZoomFactorFromPluginModel);
            }
        }
        public string NameUC;
    }
}

second dll containing viewmodels Cockpit.RUN.ViewModels.dll i have lot of plugins differents in this dll: Push_ViewModel, Switch_ViewModel....

i derive each class with the abstract class for example for the Push_ViewModel:

using Cockpit.RUN.Common;
using System.Windows;
using System.Windows.Input;

namespace Cockpit.RUN.ViewModels
{
    public class PushButton_ViewModel : PluginModel
    {

        public PushButton_ViewModel(params object[] settings)
        {
            NameUC = (string)settings[2];
            Layout = new LayoutPropertyViewModel();
        }

        public override double Left
        {
            get => Layout.UCLeft;
            set => Layout.UCLeft = value;
        }
        public override double Top
        {
            get => Layout.UCTop;
            set => Layout.UCTop = value;
        }
        public override double Width
        {
            get => Layout.Width;
            set => Layout.Width = value;
        }
        public override double Height
        {
            get => Layout.Height;
            set => Layout.Height = value;
        }                         
    }
}

one thing again, this plugin dll is loaded dynamically during the bootstrapper

    protected override IEnumerable<Assembly> SelectAssemblies()   
    {                                                                                                                                  
        var assemblies = new List<Assembly>();
        assemblies.AddRange(base.SelectAssemblies());
        assemblies.Add(Assembly.LoadFile(@"J:\ProjetC#\Cockpit-master\Cockpit.RUN.Test\bin\Debug\Cockpit.RUN.ViewModels.dll")); 
        assemblies.Add(Assembly.LoadFile(@"J:\ProjetC#\Cockpit-master\Cockpit.RUN.Test\bin\Debug\Cockpit.RUN.Views.dll")); 
        return assemblies;   
    }  

so the problem is when i want to cast each ViewModels with the abstract base PulginModel, my result is null:

        using Cockpit.RUN.Common;
                    :
                    :
        public BindableCollection<PluginModel> MyCockpitPlugins { get; set; }

                    :
                    :

        model = "Cockpit.RUN.ViewModels.PushButton_ViewModel, Cockpit.RUN.ViewModels";
        var typeClass = Type.GetType(model); // its ok 
        var viewmodel = resolutionRoot.TryGet(typeClass, param); // Its ok i have an instance of PushButton_ViewModel

        var v = viewmodel as PluginModel; //-> not ok its null
        var w = (PluginModel)viewmodel; //-> not ok its error

        // So i cant display my  list of views associated 
        MyCockpitPlugins.Add(v);

Do I have done something wrong?

assembly loaded at break debug before casting:

and the result of typeof and GetType:

typeof(PluginModel) gives {Name = "PluginModel" FullName = "Cockpit.RUN.Common.PluginModel"}

viewmodel.GetType().BaseType gives {Name = "PluginModel" FullName = "Cockpit.RUN.ViewModels.PluginModel"}

Answer 1

The interfaces (dll):

public interface IPlugin
{
    ICallbacks Callbacks { get; set; }

    string NameUC { get; set; }

    double Width { get; set; }
    double Height { get; set; }
    double Left { get; set; }
    double Top { get; set; }

    double ZoomFactorFromPluginModel { get; set; }
}
public interface ICallbacks
{
    void SomeCallback();
}

Your implementation:

public class PushButton_ViewModel : PluginModel, IPlugin
{
    // How was this going to work? Who makes the instance?
    //public PushButton_ViewModel(params object[] settings)
    //{
    //    NameUC = (string)settings[2];
    //    Layout = new LayoutPropertyViewModel();
    //}

    public ICallbacks Callbacks { get; set; }

    public override double Left
    {
        get => Layout.UCLeft;
        set => Layout.UCLeft = value;
    }
    public override double Top
    {
        get => Layout.UCTop;
        set => Layout.UCTop = value;
    }
    public override double Width
    {
        get => Layout.Width;
        set => Layout.Width = value;
    }
    public override double Height
    {
        get => Layout.Height;
        set => Layout.Height = value;
    }                         
}

Then initialize it

 Type t = Type.GetType("PushButton_ViewModel");
 object obj = FormatterServices.GetUninitializedObject(t);
 IPlugin instance = obj as IPlugin;
 instance.NameUC = "the name";
 instance.Callbacks = new CallbacksModel();