Blog

INotifyCollectionChanged

Published on Monday, June 1, 2009 In Programming Tags #architecture

There are two things I do not understand with INotifyCollectionChanged:

Why is it in the System.Collections.Specialized? System.Collections.ObjectModel or even System.Collections would have made more sense to me because it does not specialize a collection, it simply makes it observable. Why is it defined in the WindowsBase assembly? This interface could be used to build Observable collections when implementing Domain objects. But I do not want references to "windows" there, i.e. user interface related components.

ReadOnlyObservableCollection

Published on Monday, June 1, 2009 In Programming Tags #dotnet

What is the point on observing changes on a collection that is ReadOnly?

Well, I guess it is all in the name: you cannot change it but you can still know what is happening to it.

In framework 1.0 & 1.1, you had no ReadOnly implementation visible. You could create ReadOnly instances by calling static methods. I guess it was decided that it is clearer to explicitly expose the Collection as ReadOnly in the signature of the property itself, than having to read the documentation to discover it.

Implementing IBindingListView... or not

Published on Saturday, May 30, 2009 In Programming Tags #architecture

Sometimes, it is very difficult to reuse existing code.

Today I wanted to code a class implementing the IBindingListView. At first, I wanted to inherit the BindingList but then I discovered that some features were hidden, such as the AddIndex. This method is not virtual and does not delegate to an AddIndexCore method either.

Adding Design Time support to the ServingNestedContainer

Published on Tuesday, May 26, 2009 In Programming Tags #components

The ServingNestedContainer is fine but it does not support DesignTime. Therefore, if you want to still be able to benefit from the productivity improvement of the designer, you have to re-site your components.

Fortunately, it is possible to implement a component that would, through its Designer, register a CodeDomProvider that overrides the CodeDomProvider in charge of initializing of the components field.

Unleashing the wonders of the Component model

Published on Sunday, April 19, 2009 In Programming Tags #components

One of the things that made me like the .Net framework so much was the component model, along with the design time support.

At first sight, a Component looks like a stand alone piece of code you can parametrize and use in your own code. The easiest way to do so is to create a component derived class and to drop components on it. Then, the design time mechanism quicks in and you can use the PropertyGrid to set the properties and register the event listeners.