Chip,

I did review this sample earlier when you suggested it.  I got so wrapped up in 
researching the parts that I did not understand that I completely forgot the 
speak value part which was one of the few that I understood right away.  Thanks 
for sending it direct to me.  It does cover a lot of core issues in using MSAA 
directly.

Regards,
Ken Scott


From: Chip Orange [mailto:[email protected]]
Sent: Saturday, November 05, 2011 6:09 PM
To: [email protected]
Subject: RE: How to Limit Speaking of MSAA Information

Hi Ken,

Sounds like you got your answer, but in case it's of any help to you, this was 
one of the examples for scripting class #18, and I'll just put the text of the 
example file in the message below.

Chip

------

' Scripting class 18 (7/3/2011)


MSAA over-view from:
http://en.wikipedia.org/wiki/Microsoft_Active_Accessibility


MSAA communicates information by sending small chunks of information about 
elements
of a program to the assistive technology object (AT). The four critical pieces 
of
information on which the AT relies to help users interact with applications are 
an
element's role, name, value, and state:

Role: Conveys to users via AT what type of object a control is, such as a button
or a table.

Name: Provides a label for an element, such as Next on a button that moves users
to the next page, or First Name for an edit box.

Value: Provides the value of the specified object such as the value on a slider 
bar, or
the information in an editable text box. Not all objects have a value.

State: Identifies the current condition of the control, such as checked for a 
checkbox.
State advises whether a control can be selected, focused, and/or other types of 
changeable
functionality.





' example 1
' shows how to block info from WE for a particular event, using MSAA
' (based on code from the MS Access app from GW)


' in this situation, WE is speaking incorrect information when some control(s) 
get focus in MS Access.
' this app blocks the focus event from WE, and then uses the focus event to 
cause it to speak the proper information instead.

' since the window onFocus event doesn't allow you to return some special value 
to prevent WE from handling the focus event,
' we have to prevent WE from seeing the MSAA focus event at all.

' get a COM automation link to the running copy of MS Access
dim msAccessObj
On Error Resume Next
Set msAccessObj = GetObject(, "Access.Application")
On Error Goto 0


Dim myMSAAEventSource
Set myMSAAEventSource = MSAAEventSource ' make a copy of the object so we can 
modify it's properties
myMSAAEventSource.Process = ClientInformation.ApplicationProcess

' Block focus so we can handle it ourselves
Dim blockedFocusEvent
Set blockedFocusEvent = myMSAAEventSource.BlockEvent(event_OBJECT_FOCUS, 
clientInformation.ApplicationProcess)
' now, none of the window onFocus or onChildFocus events for this process will 
be spoken by WE
' but the events for the window objects will still fire for this app.

Dim msaaEventHandle
' now handle all  focus events
 msaaEventHandle = ConnectEvent(myMSAAEventSource, "OnObjectFocus", 
OnObjectFocus")

' end of main body


Sub MSAA_OnObjectFocus(accObj)
' event handler for MSAA focus events

' it tries to get the current control name and type info to be spoken from the 
MSAA event,
' and if not there, then from the COM link with MS Access.
' if it can't be found in either place, then it passes the focus event to WE, 
to allow WE to speak what it can.

    If Not accObj Is Nothing Then
  Dim handledEvent : handledEvent = False

  Dim accCopy : Set accCopy = accObj
  If Not accCopy Is Nothing Then
   Dim accWin : Set accWin = accCopy.EventWindow ' this is the window which had 
the focus event
   If Not accWin Is Nothing Then
' see if we have an active COM automation link to MS Access
    If Not msAccessObj Is Nothing Then
' have a COM automation link to MS Access, so it's possible to get info from it 
about the current control
SpeakIt ActiveControlName(accCopy), accCopy.Value, ActiveControlType(accCopy)
     handledEvent = True
    End If
   End If
  End If

  If Not handledEvent Then
' have no COM link with MS Access, so let WE speak this focus event by passing 
it on to WE
   accObj.SimulateEvent event_OBJECT_FOCUS, apAll
  End If
    End If

End Sub ' MSAA_OnObjectFocus(accObj)



Function ActiveControlName(accObj)
' if MSAA didn't supply the control name, then get it from the COM automation 
link with MS Access

    ActiveControlName = ""
 If Not accObj Is Nothing Then
  ActiveControlName = accObj.Name
  Exit Function
 End If

    Dim screenObj, activeObj
    If Not msAccessObj Is Nothing Then
        On Error Resume Next
        Set screenObj = msAccessObj.Screen
        If Not screenObj.ActiveControl Is Nothing Then
            Set activeObj = screenObj.ActiveControl
   ActiveControlName = activeObj.Name
   Exit Function
        End If
        On Error Goto 0
    End If

End Function ' ActiveControlName(accObj)


Function ActiveControlType(accObj)
' if MSAA didn't supply the control type, then get it from the COM automation 
link with MS Access

    ActiveControlType = ""

 If Not accObj Is Nothing Then
  Dim accRole : Set accRole = accObj.Role
  If Not accRole Is Nothing Then
   ActiveControlType = accRole.Text
  End If
 End If

 On Error Resume Next
    Dim screenObj, activeObj
    If Not msAccessObj Is Nothing Then
        Set screenObj = msAccessObj.Screen
  If Not screenObj Is Nothing Then
   Set activeObj = screenObj.ActiveControl
   If Not activeObj Is Nothing Then
    ActiveControlType = ControlTypeToText(activeObj.ControlType)
   End If
  End If
    End If
 On Error Goto 0

End Function ' ActiveControlType(accObj)

' end of example 1




' example 2:
' mentioned in last week's examples, I used this in the MS Office app to help 
me read a listbox which never got focus, and so was never read.
' (it also doesn't supply all the standard properties or MSAA information, such 
as which item was just selected).

' here is shown some of the code which uses MSAA to tell me when an item in the 
listbox of interest has been selected,
' then, if it's the first time, I can go look at the listbox and get the 
selection background color.
' (this isn't normally anything you would have to do, it just shows some of the 
creative things you may have to do in order to get something to speak properly).

'* in main body of app prepare for use of MSAA with:
Set myMSAAEvents = msaaEventSource ' allows us to customize which MSAA events 
to watch

' hook the  MSAA onObjectSelection events
MSAAConnection3 = ConnectEvent(myMSAAEvents, "onObjectSelection", 
"MSAA_onObjectSelection")

' limit MSAA to the VBA process:
myMSAAEvents.Process = VBAWindow.Process ' filters MSAA events for only this 
process

Sub MSAA_OnObjectSelection(access)
' event handler
' called when MSAA signals some text is selected.

' note that almost all MSAA event handlers get just one parameter, an object 
whose type is "accessible".

Dim accObj
Dim oWindow

If access Is Nothing Then Exit Sub
Set accObj = access ' make a copy of the object, because it sometimes 
"disappears" on you

' don't do anything if this isn't for a list item
On Error Resume Next
If accObj.role Is Nothing Then Exit Sub
If accObj.role.Value <> role_SYSTEM_LISTITEM Then Exit Sub
If Err.Number <> 0 Then Exit Sub ' sometimes get an error referencing the value 
property
On Error GoTo 0

' this is a list item MSAA event
On Error Resume Next
If Not accObj.State.selected Then Exit Sub

' text was selected in this list item
Set oWindow = accObj.EventWindow ' this is the window which generated the MSAA 
event
If Err.Number <> 0 Then Exit Sub

On Error GoTo 0
If  oWindow Is Nothing Then exit sub

' don't do anything if this is not a listbox window
If oWindow.Type <> wtListBox Then Exit Sub
' THIS IS a listbox control
' test to make sure it's the window we think it is
If StrComp(UCase(oWindow.parent.className), "NAMELISTWNDCLASS", vbTextCompare) 
<> 0 Then Exit Sub
' and this is the correct listbox of the correct intellisense window of MS 
Office
SpeakingIntelliSense = True
If sHighlightColor = "" Then
'  and we don't yet know the highlight color
' note: at this point the msaa_onobjectShow has already identified the listbox 
window, and has suppressed
' the speech resulting from the up/down arrows (because WE would otherwise just 
read the current line of code each time
' an arrow key is pressed when an intellisense list is open).
 sHighlightColor = highlightColorString(oWindow)
 queue "sayHighlightedItem"
End If '  sHighlightColor = ""

End Sub

' end of example 2


*** Warning ***
There is a known bug with MSAA when running under XP.
If events are being filtered by process, The MSAA events do fire as expected, 
but the parameter passed in is frequently empty (it will be empty if the author 
of the program did not explicitly handle MSAA information, but relied on 
Microsoft's "automatic" handling for standard controls).

If you plan for a large app to run under xp, you may wish to arrange a small 
test under xp, so you can see if this effects your situation.

Note: I did not receive this news in time to do my own research on the topic 
before class.


________________________________
From: Scott, Ken 
[mailto:[email protected]]<mailto:[mailto:[email protected]]>
Sent: Friday, November 04, 2011 4:25 PM
To: '[email protected]'
Subject: How to Limit Speaking of MSAA Information
Hi Window-Eyes scripters,

I am trying to limit Window-Eyes to speak only part of MSAA information for a 
focused control that changes based on cursor movement.  The MSAA elements that 
are currently spoken are: name role and value.  I only need the value spoken.

If I understand the developers reference and the MSAccessSupport app which was 
the one app that seem to be dealing with the same problem, I first have to 
block the default Window-Eyes action then script Window-Eyes to only speak the 
value portion of the MSAA string.  I think I understand the block process well 
enough to script that part.  I am not figuring out a way to speak just the 
value information.  Can anyone suggest a way or direct me to an open app that 
does something similar so I can see how someone else solved the problem?

Thanks in advance for all help.

Regards,
Ken Scott

Reply via email to