Public Class MyOwnPanel
    Inherits Windows.Forms.Panel
    Private Const WM_LBUTTONDOWN As Integer = &H201
    Protected Overrides Sub WndProc(ByRef m As System.Windows.Forms.Message)
        If Me.[ReadOnly] AndAlso m.Msg = WM_LBUTTONDOWN Then Return
        MyBase.WndProc(m)
    End Sub
    Public [ReadOnly] As Boolean
End Class

If myTodo = "view" Then
            CType(myPanel, MyOwnPanel).ReadOnly = True
End If