Entity Framework doesn't create Database - asp.net-mvc

Question

i'm creating a database with entity framework, in an mvc asp.net application, using code first.
I'm new to the argument so be patient... I've created the database for the first time and all seems to be right; but couse of i didn't create a DropCreateDatabaseIfModelChanges method to change the tables i decided to manually delete the database.
The problem is that the database is not recreating!
I've implemented the initializer and it is in a different class from the context...
public class WidgetDbInitializer : DropCreateDatabaseIfModelChanges<WidgetDbContext>
{
}
Setted it up in Global.asax.cs and forced to init that
protected void Application_Start()
{
AreaRegistration.RegisterAllAreas();
RegisterGlobalFilters(GlobalFilters.Filters);
RegisterRoutes(RouteTable.Routes);
Database.SetInitializer<Portale.Models.WidgetDbContext>(new Portale.Models.WidgetDbInitializer());
var _initer = new WidgetDbInitializer();
using (var db = new WidgetDbContext())
{
_initer.Seedit(db);
db.Database.Initialize(true);
}
}
I've just the default connection string couse now i don't care about it...
Please help me i've read tons of articles over the web and i can't get a solution...
The error i get:
System.ArgumentNullException non è stata gestita dal codice utente
Message=Il valore non può essere null.
Nome parametro: key
Source=mscorlib
ParamName=key
StackTrace:
in System.Collections.Generic.Dictionary`2.FindEntry(TKey key)
in System.Collections.Generic.Dictionary`2.TryGetValue(TKey key, TValue& value)
in System.Data.Entity.ModelConfiguration.Configuration.Mapping.SortedEntityTypeIndex.Add(EdmEntitySet entitySet, EdmEntityType entityType)
in System.Data.Entity.ModelConfiguration.Configuration.Mapping.EntityMappingService.Analyze()
in System.Data.Entity.ModelConfiguration.Configuration.Mapping.EntityMappingService.Configure()
in System.Data.Entity.ModelConfiguration.Configuration.ModelConfiguration.ConfigureEntityTypes(DbDatabaseMapping databaseMapping, DbProviderManifest providerManifest)
in System.Data.Entity.ModelConfiguration.Configuration.ModelConfiguration.Configure(DbDatabaseMapping databaseMapping, DbProviderManifest providerManifest)
in System.Data.Entity.DbModelBuilder.Build(DbProviderManifest providerManifest, DbProviderInfo providerInfo)
in System.Data.Entity.DbModelBuilder.Build(DbConnection providerConnection)
in System.Data.Entity.Internal.LazyInternalContext.CreateModel(LazyInternalContext internalContext)
in System.Data.Entity.Internal.RetryLazy`2.GetValue(TInput input)
in System.Data.Entity.Internal.LazyInternalContext.InitializeContext()
in System.Data.Entity.Internal.InternalContext.Initialize()
in System.Data.Entity.Internal.InternalContext.GetEntitySetAndBaseTypeForType(Type entityType)
in System.Data.Entity.Internal.Linq.InternalSet`1.Initialize()
in System.Data.Entity.Internal.Linq.InternalSet`1.get_InternalContext()
in System.Data.Entity.Infrastructure.DbQuery`1.System.Linq.IQueryable.get_Provider()
in System.Linq.Queryable.Join[TOuter,TInner,TKey,TResult](IQueryable`1 outer, IEnumerable`1 inner, Expression`1 outerKeySelector, Expression`1 innerKeySelector, Expression`1 resultSelector)
in Portale.Controllers.WidgetContainerController.Index() in C:\Users\doompro\Documents\Visual Studio 2010\Projects\Portale\Portale\Controllers\WidgetContainerController.cs:riga 56
in lambda_method(Closure , ControllerBase , Object[] )
in System.Web.Mvc.ActionMethodDispatcher.Execute(ControllerBase controller, Object[] parameters)
in System.Web.Mvc.ReflectedActionDescriptor.Execute(ControllerContext controllerContext, IDictionary`2 parameters)
in System.Web.Mvc.ControllerActionInvoker.InvokeActionMethod(ControllerContext controllerContext, ActionDescriptor actionDescriptor, IDictionary`2 parameters)
in System.Web.Mvc.ControllerActionInvoker.<>c__DisplayClass15.<InvokeActionMethodWithFilters>b__12()
in System.Web.Mvc.ControllerActionInvoker.InvokeActionMethodFilter(IActionFilter filter, ActionExecutingContext preContext, Func`1 continuation)
InnerException:

Answer 1

override Seed function in your WidgetDbInitializer class and try to add some data to your database .
protected override void Seed(WidgetDbContext context)
{
context.yourodel.add(new class() )
}
first check your overriden seed invoke correctly , then if your database dose not generated you will get an exception .

Answer 2

Solved the problem:
public class Widget
{
//This properties rapresent the primary key for entity framework
[Key]
public int WidgetID { get; set; }
//Foreing key to the column where this widget is stored
public virtual int ColumnID { get; set; }
//The title of the widget
public string Title { get; set; }
//Controller of the Widget, this property may be used on the RenderAction call
public string Controller { get; set; }
//ActionMethod of the Widget, this property may be used on the RenderAction call
public string ActionMethod { get; set; }
//The Type of the Model, used on deserialization
public Type ModelType { get; set; }
//The context of the widget
public string SerializedModel { get; set; }
}
The database just didn't accept the type "Type", all working fine as soon as I deleted that field... I just didn't look at it because it was working with the "Object" type, didn't expect it doesnt with Type..