Hi,

I need to develop several dialog boxes that use a common set of UI
elements. For this purpose, I've created a class (let’s call it
ucBaseFilter) that inherits from UserControl and contains lots of UI
elements and some programming logic.

Now, I need the user interface of ucBaseFilter to be user-configurable.
For that purpose, I’ve created 2 classes (ucFilter1 / ucFilter2) that
inherit from ucBaseFilter. Each one has its own interface, but the
programming logic is the same (the code is still in ucBaseFilter) and
it’s completely transparent for the dialog boxes that use the control.

- In design mode, I obviously don’t know which one of the two inherited
controls I’ll need, so I use ucBaseFilter (it’s blank, but I’m in design
mode).

- At Runtime, depending on the user settings, I need to dynamically
instanciate ucFilter1 or ucFilter2 in the New:
        If Not Me.DesignMode Then
            If MyPoste.LoadSimpleProductFilter Then
                Me.UcProdFilter = New ucFilter1
            Else
                Me.UcProdFilter = New ucFilter2
            End If
        End If

        InitializeComponent()

The problem is that in InitializeComponent, at runtime, UcProdFilter is
instanciated to ucBaseFilter. I’ve tried to change InitializeComponent
to skip that:
    <System.Diagnostics.DebuggerStepThrough()> Private Sub
InitializeComponent()
        Dim resources As System.ComponentModel.ComponentResourceManager
= New System.ComponentModel.ComponentResourceManager(GetType(myForm))
        If Me.DesignMode Then
            Me.UcProdFilter = New ucBaseFilter
        End If

but each time I open the form in the visual designer, my code is lost (I
know, I should not write code in InitializeComponenent).

Is there another  way do dynamically decide which one of the two
components will be instanciated at runtime ?

Thanks

David