Events handlers not firing on new presentations in Windows 7

[neilt17]

In an add-in I am writing, I have some ribbon controls which are designed to be activated when text has focus - and otherwise to be inactive. I use the WindowSelectionChange event to trigger reloading of the relevant controls. Unfortunately this does not work for all combinations of Office/Windows.

For Office 2016 on Windows 10, or Office 2010 on Windows 10, this works fine.

For Office 2016 or Office 2013 on Windows 7, I am not getting the WindowSelectionChange event when opening PowerPoint and creating a presentation. In fact, I don't get any event on a reference to an Application object defined with WithEvents after the NewPresentation event. My tests indicate that the relevant variable is still there - and hasn't been reset after the NewPresentation event - just that it no longer gets these events.

Note, if I open an existing presentation, then the events fire as expected, and also having opened an existing presentation and then creating a new presentation that also works as expected.

Any suggestions?

Below details of my tests:

MainModule:

Option Explicit


Public gb_oAppEvents As CApplicationEvents
Public gb_stTestVariable As String


Public gb_boolContextSet As Boolean


Public gb_oMyRibbon As IRibbonUI


Sub RibbonUI_onLoad(Ribbon As IRibbonUI)
  
   MsgBox "RibbonUI_onLoad run"
  
  If gb_oAppEvents Is Nothing Then
    Set gb_oAppEvents = New CApplicationEvents
  End If
  
  Set gb_oAppEvents.App = Application
  Set gb_oMyRibbon = Ribbon
  
  ' Check if variable retained:
  ' (We fined that it is always retained for all versions).
  gb_stTestVariable = "Variable set on load"
  
  ' Set something on the gb_oAppEvents object for testing:
  gb_oAppEvents.stVariableSet = "An Application Events variable was set when the ribbom loaded."
  
End Sub


Sub NormalControl()
  
  Dim stAppEventsVar As String
  stAppEventsVar = ""
  
  ' The global app events does not go away - this works after the ribbon has
  ' been loaded at any point:
  
  If Not gb_oAppEvents Is Nothing Then
    stAppEventsVar = vbCrLf & vbCrLf & "The value of the test " & _
         "variable on the gb_oAppEvents object is: " & gb_oAppEvents.stVariableSet
  End If


  MsgBox "You clicked a normal control. The value of the test variable is: " & _
         gb_stTestVariable & stAppEventsVar
End Sub


Sub ContextSensitiveControl()
  MsgBox "You clicked a context sensitive control"
End Sub


Sub ContextSensitiveAlwaysTrue()
  MsgBox "You clicked on the always true context sensitive control"
  
  ' We don't lose the object containing the ribbon reference - this
  ' never gets triggered:
  If gb_oAppEvents Is Nothing Then
    Set gb_oAppEvents = New CApplicationEvents
    MsgBox "Oh dear - we would have lost the ribbon as well!"
  End If
  
  ' The application object does not go away:
  If gb_oAppEvents Is Nothing Then
    MsgBox "The application object went away"
  Else
    MsgBox "The application object did not go away - reset it anyway!"
  End If
  ' reset app property - but this doesn't help - the reference application
  ' object does not respond to events.
  Set gb_oAppEvents.App = Application
 
End Sub


Sub GetEnabled(Control As IRibbonControl, ByRef returnedVal)


  ' On Windows 7 this doesn't work - because the App_WindowSelectionChange
  ' event never gets called - so gb_boolContextSet is never changed.
  ' It works fine in Windows 10 it seems.
  ' In all cases this is always called when the ribbon is invalidated.
  If Control.Id = "idContextSensitiveControl" Then
    returnedVal = gb_boolContextSet
  End If
  
  ' This works fine:
  If Control.Id = "idContextSensitiveAlwaysTrue" Then
    returnedVal = True
  End If
  
End Sub

CApplicationEvents Class:

Option Explicit


Private p_stVariableSet As String


Public WithEvents App As Application


Public Property Get stVariableSet() As String
  stVariableSet = p_stVariableSet
End Property


Public Property Let stVariableSet(value As String)
  p_stVariableSet = value
End Property


Public Sub App_WindowSelectionChange(ByVal Sel As Selection)


  ' For new presentations - where no existing document is open - this is not
  ' called on the Office 2016/Windows 7 install. However, if an existing document
  ' has been opened, before creating a new presentation, then it is called.
  ' For Office 2016 or 2010/Windows 10, this is called in all situations - i.e.
  ' for new presentations following opening of PowerPoint as well.
  
  MsgBox "The selection changed."
  
  ' This activates/de-activates ribbon controls.
  If Application.ActiveWindow.Selection.Type <> ppSelectionText Then
    MainModule.gb_boolContextSet = False
  Else
    MainModule.gb_boolContextSet = True
  End If
  
  Dim oRibbon As IRibbonUI
  Set oRibbon = MainModule.gb_oMyRibbon
  
  oRibbon.InvalidateControl "idContextSensitiveControl"


End Sub


Private Sub App_NewPresentation(ByVal Pres As Presentation)
  
  ' This gets triggered on both Windows 7 and Windows 10 installs
  
  MsgBox "New Presentation"
  
  ' This is the last event that seems to get triggered in Windows 7 on first opening
  ' of PowerPoint and creating a new presentation.


  MainModule.gb_boolContextSet = True
  
  If MainModule.gb_oMyRibbon Is Nothing Then
    MsgBox "The ribbon isn't recorded."
  Else
    Dim oRibbon As IRibbonUI
    Set oRibbon = MainModule.gb_oMyRibbon
    oRibbon.InvalidateControl "idContextSensitiveControl"
  End If
  
End Sub




Private Sub App_AfterNewPresentation(ByVal Pres As Presentation)


  ' This gets triggered on the Windows 10 install, but not the Windows 7 one.
  MsgBox "After New Presentation"
  
  If MainModule.gb_oMyRibbon Is Nothing Then
    MsgBox "The ribbon isn't recorded."
  Else
    Dim oRibbon As IRibbonUI
    Set oRibbon = MainModule.gb_oMyRibbon
    oRibbon.InvalidateControl "idContextSensitiveControl"
  End If


End Sub

This is the ribbon XML:

<customUI onLoad="RibbonUI_onLoad" xmlns="not-allowed-to-post-links">
  <ribbon startFromScratch="false">
    <tabs>
      <tab idMso="TabHome">
        <group id="idRibbonVarCheck" label="Ribbon Var Check">
          <button id="idNormalControl"
                  label="Normal"
                  imageMso="ClipArtInsert"
                  size="normal"
                  onAction="NormalControl"/>
          <button id="idContextSensitiveControl"
                  label="Context Sensitive"
                  imageMso="MailMergeGoToPreviousRecord"
                  size="normal"
                  onAction="ContextSensitiveControl"
                  getEnabled="GetEnabled"/>
          <button id="idContextSensitiveAlwaysTrue"
                  label="Context True"
                  imageMso="MailMergeGoToPreviousRecord"
                  size="normal"
                  onAction="ContextSensitiveAlwaysTrue"
                  getEnabled="GetEnabled"/>
        </group>
      </tab>
    </tabs>
  </ribbon>
</customUI>

[John Wilson]

Seems to work OK here in Windows 7 Office 365

I have attached the file i made from your code and a video of enable working https://www.screencast.com/t/D3rEfPok

[neilt17]

Brilliant - thank you very much for looking at this - it prompted me to look for an alternative reason - and I think I've found it:

If "Show the Start screen when this application starts" is checked (see File -> Options -> General) then the problem I described occurs, if it is unchecked then it goes away.

[neilt17]

I found a discussion on this issue...

[neilt17]

See:
https://social.msdn.microsoft.com/Fo...=officegeneral

[John Wilson]

Interesting but I'm not seeing that.

I would suggest though that you DON'T use onLoad to instantiate gb_oAppEvents but do it with an Auto_Open Sub which will run when the AddIn loads. (probably earlier)

 Sub Auto_Open() 
Set gb_oAppEvents.EV = Application
 End Sub

[neilt17]

Great, thank you - Auto_Open() is working consistently across my various installations of office.