Saturday, October 25, 2008

Start Menu handler using Accessibility API

The code below demonstrates how to run an application from Start menu using accessibility API in TestPartner making use of VBA. For this exercise, we will use Test Script, Class Module and Module. The original intent was to have the functionality built into class module and instantiate it in Test Script. But AddressOf operator does not work inside a class module in VBA hence using Module. Anyway, first let us define the class module. For this exercise name it CStartMenuController. See below for the code (save this as CStartMenuController):
'------------------------------------------------------------------------------
' Develop by    : Techno.Scavenger
' Licensed to   : Mankind
' Date          : 26Oct2008 @ 1:39 AM + 8 GMT (Sunday @home)
' Warranty
' THE SOFTWARE IS PROVIDED “AS IS”, WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
' IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
' FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
' “Techno.Scavenger” OR ANY OTHER CONTRIBUTOR BE LIABLE FOR ANY CLAIM,
' DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR
' OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE
' USE OR OTHER DEALINGS IN THE SOFTWARE.
' Note:
' You can do whatever with this code
'------------------------------------------------------------------------------

'References:
'http://msdn.microsoft.com/en-us/library/ms697639(VS.85).aspx
'http://www.microsoft.com/downloads/details.aspx?familyid=3755582A-A707-460A-BF21-1373316E13F0&displaylang=en
'http://support.microsoft.com/kb/315519
'http://blogs.msdn.com/oldnewthing/archive/2004/04/23/118893.aspx
'http://www.eggheadcafe.com/software/aspnet/32676356/toolbarwindow32-button-in.aspx
'http://msdn.microsoft.com/en-us/library/ms696152(VS.85).aspx
'http://msdn.microsoft.com/en-us/library/ms971323.aspx
'Caret Tracking
'http://www.geocities.com/krishnapg/EventTracking.html
'-------------------------------------------------------
'Visual Basic Related
'http://www.brainbell.com/tutors/Visual_Basic/Retrieving_Accessibility_Information.htm
'sample code with hooks to AA
'http://www.eggheadcafe.com/software/aspnet/31694003/please-help-ie-window-do.aspx
'http://www.jsware.net/jsware/vbcode.php5#acc
'Notes:
'Seems like in VB, there is no need to call VariantClear for variants defined as [out] in API.

Option Explicit

'references
'Accessibility  - oleacc.dll

Private Declare Function AccessibleObjectFromEvent Lib "oleacc" (ByVal hwnd As Long, ByVal dwId As Long, ByVal dwChildId As Long, ppacc As IAccessible, pvarChild As Variant) As Long
Private Declare Sub OutputDebugString Lib "kernel32" Alias "OutputDebugStringA" (ByVal lpOutputString As String)
Private Declare Function SetWinEventHook Lib "user32.dll" (ByVal eventMin As Long, ByVal eventMax As Long, ByVal hmodWinEventProc As Long, ByVal pfnWinEventProc As Long, ByVal idProcess As Long, ByVal idThread As Long, ByVal dwFlags As Long) As Long
Private Declare Function UnhookWinEvent Lib "user32.dll" (ByVal lHandle As Long) As Long

'event constants
Private Const EVENT_OBJECT_CREATE = &H8000&         ' // hwnd + ID + idChild is created item
Private Const EVENT_OBJECT_DESTROY = &H8001&        '// hwnd + ID + idChild is destroyed item
Private Const EVENT_OBJECT_SHOW = &H8002&           '// hwnd + ID + idChild is shown item
Private Const EVENT_OBJECT_HIDE = &H8003&           '// hwnd + ID + idChild is hidden item
Private Const EVENT_OBJECT_FOCUS = &H8005&          '// hwnd + ID + idChild is focused item
Private Const EVENT_OBJECT_LOCATIONCHANGE = &H800B& '// hwnd + ID + idChild is moved/sized item
Private Const WINEVENT_OUTOFCONTEXT = &H0&          '// Events are ASYNC
Private Const WINEVENT_SKIPOWNPROCESS = &H2&        '// Don't call back for events on installer's process

'class private stuff
Private m_hHook As Long
Private m_sMenuPath As String

Private Sub Class_Initialize()
   Include "Common.MStartMenuController"
   m_hHook = SetWinEventHook(EVENT_OBJECT_FOCUS, EVENT_OBJECT_FOCUS, 0&, AddressOf MStartMenuController.WinEventFunc, 0, 0, WINEVENT_SKIPOWNPROCESS)
End Sub

Private Sub Class_Terminate()
   Dim lRet As Long
  
   If m_hHook <> 0 Then
       lRet = UnhookWinEvent(m_hHook)
   End If
End Sub

Public Sub SelectMenu(sMenuPath As String)
   MStartMenuController.SelectMenu sMenuPath
End Sub
As mentioned above, we need a module to house the function we supply to SetWinEventHook. And this is also where most of the action happens. See below for the code, save this as MStartMenuController:
'------------------------------------------------------------------------------
' Develop by    : Techno.Scavenger
' Licensed to   : Mankind
' Date          : 26Oct2008 @ 1:39 AM + 8 GMT (Sunday @home)
' Warranty
' THE SOFTWARE IS PROVIDED “AS IS”, WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
' IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
' FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
' “Techno.Scavenger” OR ANY OTHER CONTRIBUTOR BE LIABLE FOR ANY CLAIM,
' DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR
' OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE
' USE OR OTHER DEALINGS IN THE SOFTWARE.
' Note:
' You can do whatever with this code
'------------------------------------------------------------------------------

'references
'Accessibility  - oleacc.dll

Option Explicit

Private Declare Function AccessibleObjectFromEvent Lib "oleacc" (ByVal hwnd As Long, ByVal dwId As Long, ByVal dwChildId As Long, ppacc As IAccessible, pvarChild As Variant) As Long
Private Declare Sub keybd_event Lib "user32" (ByVal bVk As Byte, ByVal bScan As Byte, ByVal dwFlags As Long, ByVal dwExtraInfo As Long)
Private Declare Sub OutputDebugString Lib "kernel32" Alias "OutputDebugStringA" (ByVal lpOutputString As String)
Private Declare Sub SleepEx Lib "kernel32" Alias "Sleep" (ByVal dwMilliseconds As Long)

'key constants
Private Const KEYEVENTF_KEYUP = 2
Private Const vbKeyControl = 17
Private Const vbKeyEscape = 27
'event constants
Private Const EVENT_OBJECT_CREATE = &H8000&         '// hwnd + ID + idChild is created item
Private Const EVENT_OBJECT_DESTROY = &H8001&        '// hwnd + ID + idChild is destroyed item
Private Const EVENT_OBJECT_SHOW = &H8002&           '// hwnd + ID + idChild is shown item
Private Const EVENT_OBJECT_HIDE = &H8003&           '// hwnd + ID + idChild is hidden item
Private Const EVENT_OBJECT_FOCUS = &H8005&          '// hwnd + ID + idChild is focused item
Private Const EVENT_OBJECT_LOCATIONCHANGE = &H800B& '// hwnd + ID + idChild is moved/sized item

'private data
Private m_sMenuPath As String
Private m_sActiveItem As String

Public Function WinEventFunc(ByVal hHook As Long, ByVal lEvent As Long, ByVal hwnd As Long, ByVal idObject As Long, ByVal idChild As Long, ByVal idEventThread As Long, ByVal dwmsEventTime As Long) As Long
   Dim ObA As IAccessible
   Dim lRet As Long
   Dim v As Variant
   Dim s As String, s1 As String, sName As String
   Dim sTmp As String
  
   On Error Resume Next
   sTmp = "YH"
   Select Case lEvent
       'Case EVENT_OBJECT_CREATE, EVENT_OBJECT_DESTROY, EVENT_OBJECT_SHOW, EVENT_OBJECT_HIDE, EVENT_OBJECT_FOCUS, EVENT_OBJECT_LOCATIONCHANGE
       Case EVENT_OBJECT_FOCUS
           lRet = AccessibleObjectFromEvent(hwnd, idObject, idChild, ObA, v)
           If lRet = 0 Then
               sTmp = sTmp & ":Name:<" & ObA.accName(v)                 sTmp = sTmp & ">:Description:< " & ObA.accDescription(v)                 sTmp = sTmp & ">:Role<: " & ObA.accRole(v)                 sTmp = sTmp & ">:State<: " & ObA.accState(v)                 sTmp = sTmp & ">:menu<: " & m_sMenuPath                 m_sActiveItem = ObA.accName(v)             End If             OutputDebugString sTmp     End Select      WinEventFunc = 0        End Function  Public Function SetMenuPath(sMenuPath As String) As Boolean     m_sMenuPath = sMenuPath End Function Public Sub SelectMenu(sMenuPath As String)     m_sMenuPath = sMenuPath     StartMenuEx sMenuPath End Sub Private Sub StartMenuEx(sMenuPath As String)     Const MAX_LOOPS = 50          Dim vMenu As Variant     Dim iDx As Integer     Dim sMenuBookMark As String     Dim iTerminateCounter               vMenu = Split(sMenuPath, "~")       Call keybd_event(vbKeyControl, 0, 0, 0)     Call keybd_event(vbKeyEscape, 0, 0, 0)        ' Release the two keys     Call keybd_event(vbKeyControl, 0, KEYEVENTF_KEYUP, 0)     Call keybd_event(vbKeyEscape, 0, KEYEVENTF_KEYUP, 0)     SleepEx 1000          For iDx = 0 To UBound(vMenu)                  Do While m_sActiveItem <> vMenu(iDx)
           OutputDebugString "YH: Sending DOWN key"
           SendKeys "{DOWN}", True
           SleepEx 1000
          
           'set book on first loop thru menu indexes
           If sMenuBookMark = "" Then
               sMenuBookMark = m_sActiveItem
           Else
               'if we are here, then this must have been after one round
               'we have come full circle, need to raise an error
               If m_sActiveItem = sMenuBookMark Then
                   OutputDebugString "YH: We have come full circle, raising an error"
                   Include "Common.CustomErrorConstants"
                   Err.Raise CustomErrorConstants.vbErrMenuNotFound, "MStartMenuController", "Menu was not found"
               End If
           End If
                      
           'another check if we have gone wild
           iTerminateCounter = iTerminateCounter + 1
           If iTerminateCounter >= MAX_LOOPS Then
               OutputDebugString "YH:Max loops detected, raising an error"
               Err.Raise CustomErrorConstants.vbErrMenuNotFound, "MStartMenuController", "Menu was not found"
           End If
       Loop
      
       'clear bookmark
       sMenuBookMark = ""
       'reset terminate marker
       iTerminateCounter = 0
      
       'move to next menu
       OutputDebugString "YH:Sending RIGHT key"
       SendKeys "{RIGHT}", True
   Next
  
   'assume we found the item, then hit on enter key
   If vMenu(UBound(vMenu)) = m_sActiveItem Then
       OutputDebugString "YH: We are about to run " & m_sActiveItem
       SendKeys "~", True
   Else
       MsgBox "nah, not found"
   End If
End Sub

To make the code a little modular, we have separated custom error constants for use when raising our custom Error. See below for constant definitions and save this as CustomErrorConstants.
'------------------------------------------------------------------------------
' Developed by  : Techno.Scavenger
' Licensed to   : Mankind
' Date          : 26Oct2008 @ 1:39 AM + 8 GMT (Sunday @home)
' Warranty
' THE SOFTWARE IS PROVIDED “AS IS”, WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
' IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
' FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
' “Techno.Scavenger” OR ANY OTHER CONTRIBUTOR BE LIABLE FOR ANY CLAIM,
' DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR
' OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE
' USE OR OTHER DEALINGS IN THE SOFTWARE.
' Note:
' You can do whatever with this code
'------------------------------------------------------------------------------

Option Explicit

'Menu not found
Public Const vbErrMenuNotFound = vbObjectError + 4
Now, how do we use it? We it is quite easy actually. See below for a sample code that runs HyperTerminal. Save it as scratch or whatever suites you best.
'------------------------------------------------------------------------------
' Develop by    : Techno.Scavenger
' Licensed to   : Mankind
' Date          : 26Oct2008 @ 1:39 AM + 8 GMT (Sunday @home)
' Warranty
' THE SOFTWARE IS PROVIDED “AS IS”, WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
' IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
' FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
' “Techno.Scavenger” OR ANY OTHER CONTRIBUTOR BE LIABLE FOR ANY CLAIM,
' DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR
' OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE
' USE OR OTHER DEALINGS IN THE SOFTWARE.
' Note:
' You can do whatever with this code
'------------------------------------------------------------------------------

Option Explicit

Sub Main()

   Include "Common.CStartMenuController"
  
   Dim sm As CStartMenuController
   Set sm = New CStartMenuController
   sm.SelectMenu "All Programs~Accessories~Communications~HyperTerminal"
   Set sm = Nothing
End Sub
Notes: This code is targeted for TestPartner 6.1.x. This should work with any VBA host but you need to adjust a few things. This is also inteneded to work only with Start Menu set to Windows XP style. It should be easy to adapt this for both classic and XP start menu. Enjoy! TS

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