New Posts New Posts RSS Feed: Error adding to manager
  FAQ FAQ  Forum Search   Calendar   Register Register  Login Login

Error adding to manager
 Post Reply Post Reply
Author
  Share Topic Share Topic  Topic Search Topic Search  Topic Options Topic Options
smi-mark View Drop Down
DevForce MVP
DevForce MVP
Avatar

Joined: 24-Feb-2009
Location: Dallas, Texas
Posts: 343 		Post Options Post Options   Quote smi-mark Quote  Post ReplyReply Direct Link To This Post Topic: Error adding to manager
    Posted: 14-Nov-2011 at 2:24pm
I'm getting the following error while trying to add an entity to the manager:

Null or pending entities cannot be modified

This is the layout of the data:

User
  UserId

UserProduct
  UserProductId
  UserId
  ProductId

Product
  ProductId

This is the code I am using that fails:

        public void AddProduct(Product product)
        {
            var userProduct = new UserProduct
                                  {
                                      UserId = UserId,
                                      ProductId = product.ProductId
                                   };
            EntityAspect.EntityManager.AddEntity(userProduct);
        }

I have tried it with or without setting ProductId = product.ProductId

User.EntityAspect.IsNullOrPendingEntity = false
User.UserProducts IsPendingEntityList = false

What is very interesting is, sometimes if I set breakpoint on the AddEntity line, wait a few seconds, then let it execute, it works.

The detached entity is trying to resolve something and it is failing initially.

This is the stacktrace:

   at IdeaBlade.EntityModel.EntityAspect.SetValueWithChangeNotification(DataEntityProperty property, Object newValue)
   at IdeaBlade.EntityModel.EntityManager.GenerateId(Object entity, DataEntityProperty entityProperty)
   at IdeaBlade.EntityModel.EntityManager.UpdatePkIfNeeded(EntityAspect aspect)
   at IdeaBlade.EntityModel.EntityManager.AttachEntityAspect(EntityAspect aspect, EntityState entityState)
   at IdeaBlade.EntityModel.EntityManager.<>c__DisplayClass60.<AddOrAttachRelatedEntities>b__5d(EntityAspect w)
   at IdeaBlade.Core.EnumerableFns.ForEach[T](IEnumerable`1 items, Action`1 action)
   at IdeaBlade.EntityModel.EntityManager.AddOrAttachRelatedEntities(EntityAspect wrapper, EntityState entityState)
   at IdeaBlade.EntityModel.EntityManager.AttachEntityAspect(EntityAspect aspect, EntityState entityState)
   at IdeaBlade.EntityModel.EntityManager.AttachEntity(Object entity, EntityState entityState)
   at IdeaBlade.EntityModel.EntityManager.AddEntity(Object entity)
   at Spindlemedia.Models.Security.User.AddProduct(Product product)

At the time of the exception:

UserProduct is successfully added to the manager, with a generated id of -100 and it is in the Added State

UserProduct.Product.EntityAspect.IsNullOrPendingEntity = true
UserProduct.User.EntityAspect.IsNullOrPendingEntity = false

They are both in the same entity manager, so I'm not sure what the issue is.

Thoughts?



Edited by smi-mark - 14-Nov-2011 at 2:27pm
Back to Top
smi-mark View Drop Down
DevForce MVP
DevForce MVP
Avatar

Joined: 24-Feb-2009
Location: Dallas, Texas
Posts: 343 		Post Options Post Options   Quote smi-mark Quote  Post ReplyReply Direct Link To This Post Posted: 14-Nov-2011 at 2:34pm
I have found what is causing it.

In my ViewModel I have a collection changed event listening for UserProducts to change. This event is fired before the product has been set on UserProduct.  When I comment the collection changed code, it works flawlessly.

When this collection changes I have the following code:

   private void UserProductsChanged(object sender, NotifyCollectionChangedEventArgs e)
        {
           NotifyOfPropertyChange(() => UserProducts);
        }

        public IEnumerable<Product> UserProducts
        {
            get { return User.UserProducts.Select(up => up.Product); }
        }


This appears to be the solution:

        public void AddProduct(Product product)
        {
            var userProduct = new UserProduct
                                  {
                                      ProductId = product.ProductId
                                  };
            EntityAspect.EntityManager.AddEntity(userProduct);
 
            userProduct.UserId = UserId;
        }

This way the product is getting resolved before I attach it to the user (Which fires off the collection event)





Edited by smi-mark - 14-Nov-2011 at 2:37pm
Back to Top
 Post Reply Post Reply

Forum Jump Forum Permissions View Drop Down