> > The notification isn't that hard. Actually it's a 1 minute
> job. >It's
> the state of the average control you can buy (including
> >the datagridview and datagrid controls shipped by MS, these also have
> problems) which is much harder to deal with.
>
> I was thinking more in terms of when your business object
> implements INotifyPropertyChanged. OK, it's not that hard but
> BindingList automagically subscribe to them to make the
> control redraw when they change, which is nice.
That's indeed a hidden 'feature' and obscure. BindingSource is another
one which has these kind of tactics.
> > Microsoft's documentation has a tendency of
> explaining even the
> >most stupidist silly things an average joe will run into, but when
> >framework developers (you know, the people who write a
> framework >with .net) need documentation, it's hardly there (or
> >stating the obvious. "Gee, the property Handler returns a handler")
>
> Hehe, yeah. I'm particularly intrigued by the documentation
> of IBindingList.AddNew in MSDN (last sentence).
>
> [Note]
> "If the objects in this list implement the IEditableObject
> interface, calling the CancelEdit method should discard an
> object, not add it to the list, when the object was created
> using the AddNew method. The object should only be added to
> the list when the IEditableObject.EndEdit method is called.
> Therefore, you must sychronize the object and the list carefully."
>
> One minute job... maybe after you spent a week decoding this note.
:)
Okok, I should have stated more precise what I meant. An hour before I
wrote that remark I had implemented IBindingList on
some old collectionbase deriving code to make it work with a grid more easily,
and to enable the events to do so took less than a
minute.
> > ...In which case you have to implement IListSource which
> returns
> > the actual
> > binding object to the grid and on which you implement
> ITypedList and
> > IBindingList on.
>
> Yeah, IListSource might be the way to go in my situation. I
> don't want users of my collections to use AddNew to save a
> line of code and then come complaining about performance when
> they don't even use data bindning. Then I can also get a
> better implementation of the case of "mark for delete" at
> IList.RemoveAt...
IListSource is indeed a good solution for this, so you can implement
ITypedList, IBindingList and other goo on the object
returned by IListSource.
It's not easy though, to create view-style collections on another
collection.
FB
===================================
This list is hosted by DevelopMentor® http://www.develop.com
View archives and manage your subscription(s) at http://discuss.develop.com
