Application.ActiveWindow.ViewType not working right

Question

Why does this code in VSTO rerun a 9 (ppViewnormal) instead of a 7 (PpViewType.ppViewMasterThumbnails) even though it is in MasterThumbnails view

      Globals.ThisAddIn.Application.ActiveWindow.ViewType = PpViewType.ppViewMasterThumbnails

        MsgBox(Globals.ThisAddIn.Application.ActiveWindow.ViewType)

Same in VBA

    Application.ActiveWindow.ViewType = PpViewType.ppViewMasterThumbnails

    MsgBox (Application.ActiveWindow.ViewType)

If I substitute Windows(1) for  ActiveWindow same thing

my macro will not work in slidemaster mode and I want to test if the software is in that mode before proceeding

Answer 1

If you are in slidemaster view viewtype always returns 9 (incorrectly)

Something like this might tell you which view you are in

   If ActiveWindow.ViewType = 9 Then

      If ActiveWindow.Panes(2).ViewType = ppViewSlideMaster Then

         MsgBox "You are in Slide Master View. Please switch to Normal View.", vbExclamation, strMBTitle

         Exit Sub

      End If

   End If

Answer 2

Based on John answer I wrote this (VBA) which I found was useful

Sub WhatViewPanesAreOpen()

    Dim opn    As Pane

    Dim cnt    As Integer

    cnt = 0

    Debug.Print "Pane Count = " & ActiveWindow.Panes.Count

    For Each opn In ActiveWindow.Panes

        cnt = cnt + 1

        'Debug.Print opn.ViewType

        Select Case opn.ViewType

            Case 1

                Debug.Print " Pane " & cnt; " =  ppViewSlide (1)"

            Case 2

                Debug.Print " Pane " & cnt; " =  ppViewSlideMaster (2)"

            Case 3

                Debug.Print " Pane " & cnt; " =  ppViewNotesPage (3)"

            Case 4

                Debug.Print " Pane " & cnt; " =  ppViewHandoutMaster (4)"

            Case 5

                Debug.Print " Pane " & cnt; " =  ppViewNotesMaster (5)"

            Case 6

                Debug.Print " Pane " & cnt; " =  ppViewOutline (6)"

            Case 7

                Debug.Print " Pane " & cnt; " =  ppViewSlideSorter (7)"

            Case 8

                Debug.Print " Pane " & cnt; " =  ppViewTitleMaster (8)"

            Case 9

                Debug.Print " Pane " & cnt; " =  ppViewNormal (9)"

            Case 10

                Debug.Print " Pane " & cnt; " =  ppViewPrintPreview (10)"

            Case 11

                Debug.Print " Pane " & cnt; " =  ppViewThumbnails (11)"

            Case 12

                Debug.Print " Pane " & cnt; " =  ppViewMasterThumbnails (12)"

        End Select

    Next

End Sub