2 minute read
I seam to be having a little problem. Now, this may be me being stupid, but I can’t get an ObservableCollection to work if you pass it a generic type!
For example, consider the following code:
Public Class ItemBitCollection(Of TItem) Inherits ObservableCollection(Of ItemBit(Of TItem)) End Class Public Class ItemBit(Of TItem) Private m_item As TItem End Class
Now, if you create an instance of ItemBitCollection you will see an error on the IDE regardless of wither you use a custom object type or a String type to initialise it:
Why does this not work? What is ObservableCollection doing that maybe it should not? Time to get Reflector out…
After some looking at the source I am still none the wiser. Even if you dumb down your classes to the bare minimum you cant pass a generic type into an ObservableCollection.
This is a limitation if you ask me…
Annoying solution:
If you create a fixed class type:
Public Class ItemBitCollection(Of TItemBit) Inherits ObservableCollection(Of TItemBit) End Class Public MustInherit Class ItemBit(Of TItem) Private m_item As TItem End Class Public Class DefaultItemBit Inherits ItemBit(Of String) End Class
And then pass that class in it does work:
Dim o As New ItemBitCollection(Of DefaultItemBit)
Although this is a work around, it causes other problems in my code… Ahh well… worth a try…
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