Getting the proverbial "Object reference not set to an instance of an object" error?

I've created a class that inherits the System.Windows.Forms.TabPage class. I'm not sure how to declare an instance of the class. There needs to be an instance for each TabPage created on a specific TabControl. I basically set this new property in the "SelectedIndexChanged()" Event. I'm getting Object Reference error because I'm not sure how to declare the variable.

New Class
Public Class tabPageViewed
    Inherits System.Windows.Forms.TabPage

    Private _viewed As Boolean

    Property TabViewed() As Boolean
        Get
            TabViewed = _viewed
        End Get
        Set(value As Boolean)
            _viewed = value
        End Set
    End Property

End Class

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What is the difference in the two statements below?

'Statement 1
     Private tabV() As tabPageViewed

'Statement 2
     Private tabV As New tabPageViewed()

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How should it be declare with regard to the context in which I'm using it. I only set and check this property in the "SelectedIndexChanged()" Event.

Thanks!
BlakeMcKennaAsked:
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BlakeMcKennaAuthor Commented:
Here is how I'm using the class

    Private Sub tabChannelTestLoad_SelectedIndexChanged(sender As Object, e As EventArgs) Handles tabChannelTestLoad.SelectedIndexChanged
        Try
            EH.ErrorMessage = String.Empty

            idx = tabChannelTestLoad.SelectedIndex

            If tabChannelTestLoad.SelectedIndex <> -1 And Not clsTabViewed.TabViewed Then
                clsTabViewed.TabViewed = True

                Perform various functions...

            End If

ProcessMessage:

        Catch ex As Exception
            EH.ErrorMessage = "frmCalibration_3/tabChannelTestLoad_SelectedIndexChanged() - " & ex.Message & "...Contact Engineering!" & "~E"
        End Try

        EH.ProcessMessages(Me, sbr, EH.ErrorMessage)
    End Sub

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käµfm³d 👽Commented:
What is the difference in the two statements below?
The first line declares an uninitialized array of tabPageViewed. The second declares and instantiates a new tabPageViewed object.
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BlakeMcKennaAuthor Commented:
How should I declare it with reference to how I'm using it?

See post 40881158!
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BlakeMcKennaAuthor Commented:
Thanks!
0
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