Matthieu MEZIL : WPF

EDM Designer V0.9

Matthieu MEZIL — Mon, 09 Feb 2009 23:37:00 GMT

My first EDM Designer version was a viewer. It's now a real designer.

You can realize all the EDM mapping scenarii without writing xml yourself! ... except for Functions mapping (with Stored Procedures).

I am very happy to see the interest of some of you on this project and I am sorry to be so slow but, you have to understand that I work on it only at night and moreover, I have a wife and two children, so I haven't got as much time as I want to do it.

Remember that it's my first WPF project. So the code is probably not perfect. Moreover, my tests are near to zero so there are probably some bugs. If you find one, please send me an email at "matthieu.mezil at winwise.fr". If you have some WPF advices, you can also send me an email.

In the next version, I will try to integrate it in VS.

EDM Designer

Matthieu MEZIL — Wed, 07 Jan 2009 09:36:00 GMT

I didn’t blog for a (too) long time which is strange for me.

I received some emails asking if I was ok and I found in this a similitude between Scott Guthrie and myself. Lol

So what did I do during my nights this last month? No I don’t sleep more and no I wasn’t in a 6 weeks’ vacation.

In fact, I'm beginning a very funny project: doing an EDM designer! And I thought that it was time I did my first WPF project.

If you look at the code, you will see a VB project. Yes Julie, you read well. This project is used to write an edmx file from my classes and, instead of using serialization, I choose to play with VB9 XML Literal. For all other projects, I use C# of course.

The first version is only a CSDL read-only designer.

I think it makes two interesting points compared to the current MS designer:

The ability to show only some entity types and not all
The ability to show Complex Type

What do I want to add in the following versions?

The ability to add or remove csdl type / property / relation / inheritance (fixing these bugs of course) and to save it into an edmx file
The ability to change csdl type / property properties like the name, the visibility, etc.
The ability to show and change the mapping (including TPC which isn’t supported by current MS designer)
The ability to (re)generate csdl entity types from ssdl entity types. (In current MS designer, it generates it when you add the table / view from the wizard but if you delete your csdl entity type, you have to regenerate it yourself or to delete your ssdl entity type and to use the wizard to add it again. Moreover, for SSDL View, you have nothing to generate the CSDL entity type)
The ability to add SSDL Views or Functions
Integrate it in VS
The ability to save your designer

You can download it here.

As I said previously, I am a WPF beginner so if you have time to audit it and if you have some remarks, advices, criticism, post a comment please.

EF and WPF

Matthieu MEZIL — Fri, 29 Aug 2008 20:07:00 GMT

I had a question today which allow me to do my first WPF poject.

The guy told me that he has a master detail scenario with two windows: one to edit masters and one to edit details. In details, he wants to choose the master with a combo.

He wants that when he adds one master, the combo adds it also without having to rebind it and without having to save the context.

How to do this?

I developp a class for this:

public class ContextEntitiesLoaded<T> : IEnumerable<T>, INotifyCollectionChanged
{
    private ObjectContext _context;
    private EntityState _states = EntityState.Added | EntityState.Modified | EntityState.Unchanged;
 
    public ContextEntitiesLoaded(ObjectContext context)
    {
        _context = context;
        _context.ObjectStateManager.ObjectStateManagerChanged += (sender, e) =>
        {
            if (e.Element is T)
                switch (e.Action)
                {
                    case CollectionChangeAction.Add:
                    case CollectionChangeAction.Remove:
                        if (e.Element is T)
                            OnNotifyCollectionChanged();
                        break;
                }
        };
    }
 
    public EntityState States
    {
        get { return _states; }
        set { _states = value; }
    }
    public Func<T, object> SortExpression { get; set; }
 
    protected virtual void OnNotifyCollectionChanged()
    {
        if (CollectionChanged != null)
            CollectionChanged(this, new NotifyCollectionChangedEventArgs(NotifyCollectionChangedAction.Reset));
    }
 
    #region IEnumerable<T> Members
    public IEnumerator<T> GetEnumerator()
    {
        var q = _context.ObjectStateManager.GetObjectStateEntries(States).Select(se => se.Entity).OfType<T>();
        if (SortExpression != null)
            q = q.OrderBy(SortExpression);
        return q.GetEnumerator();
    }
    #endregion
    #region IEnumerable Members
    System.Collections.IEnumerator System.Collections.IEnumerable.GetEnumerator()
    {
        return GetEnumerator();
    }
    #endregion
 
    #region INotifyCollectionChanged Members
    public event NotifyCollectionChangedEventHandler CollectionChanged;
    #endregion
}

Then I need to get all the classes in the context and to bind them on the combo:

public partial class Window1 : Window
{ 
    public Window1()
    {
        InitializeComponent();
        ObjectDataProvider odp = this.FindResource("maSource") as ObjectDataProvider;
        if (odp != null)
        {
            foreach (var c in NorthwindEntities.Instance.Categories); // to load the categories on the context
            odp.ObjectInstance = new ContextEntitiesLoaded<Category>(NorthwindEntities.Instance) { SortExpression = c => c.CategoryName };
        }
    }
 
    [...]
}