Question : getting the hwnd or dc for access form

i'm playing around with stretchblt in access, the problem is that when i stretchblt to an access form it only draws on the record selector bar and not on the detail part.. so i guess i want to get the hwnd or dc of the detail section of the form .

i found an enumeratechildwindows excel example at http://www.appspro.com/Tips/VBA%20Tips.htm, but i dont know how to convert it to work with access.

to see what i mean try a blank form (make sure record selectors are enabled) with the following code:

Code Snippet:

         
           
             1:
2:
3:
4:
5:
6:
7:
8:
9:
10:
11:
12:
13:
14:
15:
16:
17:
18:
19:
20:
21:
22:
23:
24:
25:
26:
27:
28:
29:
30:
31:
32:
33:
34:
35:
36:
37:
38:
39:
40:
41:
42:
43:
44:
45:
46:
47:
48:
49:
50:
51:
52:
53:
54:
55:
56:
57:
58:
59:
60:

           
           
             Option Compare Database
Private Declare Function GetCursorPos Lib "user32" (lpPoint As POINTAPI) As Long
Private Declare Function FindWindow Lib "user32" Alias "FindWindowA" (ByVal lpClassName As String, ByVal lpWindowName As String) As Long
Private Declare Function FindWindowEx Lib "user32" Alias "FindWindowExA" (ByVal hWnd1 As Long, ByVal hWnd2 As Long, ByVal lpsz1 As String, ByVal lpsz2 As String) As Long
Private Declare Function GetDC Lib "user32" (ByVal hwnd As Long) As Long
Private Declare Function StretchBlt Lib "gdi32" (ByVal hdc As Long, ByVal x As Long, ByVal y As Long, ByVal nWidth As Long, ByVal nHeight As Long, ByVal hSrcDC As Long, ByVal xSrc As Long, ByVal ySrc As Long, ByVal nSrcWidth As Long, ByVal nSrcHeight As Long, ByVal dwRop As Long) As Long
Private Declare Function GetDesktopWindow Lib "user32" () As Long
Private Declare Function ReleaseDC Lib "user32" (ByVal hwnd As Long, ByVal hdc As Long) As Long

'Mouse position type
Private Type POINTAPI
        x As Long
        y As Long
End Type

Private Const SRCCOPY = &HCC0020 ' (DWORD) dest = source

Dim dsktp As Long, St As Long, PP As POINTAPI 'Some variables
Private Sub Detail_Click()
MsgBox Application.Forms("form1").hwnd
MsgBox Detail.Application.hWndAccessApp
End Sub

Private Sub Form_Load()
 'this is modified code from "The Start Button Cam By Tomer Cohen:" & vbCrLf & vbCrLf & "http://come.to/Tomer-C", vbInformation, "Tomer Cohen"

    Dim Wind As Long 'Temporary hwnd holder
    
    'Finding the SystemTray Window (hwnd)
    Wind = FindWindow("Shell_TrayWnd", "")
    
    'Finding the Start Button Window (hwnd)
    Wind = FindWindowEx(Wind, 0, "Button", vbNullString)
    
    'Getting Start Button DC
   ' St = GetDC(Application.Forms("form1").hwnd)
       St = GetDC(Form.hwnd)
    'Getting the Desktop window hwnd
    Wind = GetDesktopWindow()
    
    'Getting the Desktop window DC
    dsktp = GetDC(Wind)
    
    'Timer1.Enabled = True
End Sub

Private Sub Form_Timer()
 GetCursorPos PP
    
    'Drawing the mouse's background on the Start Button
    StretchBlt St, 0, 0, 480, 200, dsktp, PP.x - 30, PP.y - 12.5, 240, 100, SRCCOPY
End Sub

Private Sub Form_Unload(Cancel As Integer)
   'Relesing the Start Button DC
    ReleaseDC hwnd, St
    
    'Releasing the Desktop Window DC
    ReleaseDC hwnd, dsktp
End Sub

           
         

Open in New Window

Select All

Answer : getting the hwnd or dc for access form

Option Compare Database
Private Declare Function GetCursorPos Lib "user32" (lpPoint As POINTAPI) As Long
Private Declare Function FindWindow Lib "user32" Alias "FindWindowA" (ByVal lpClassname As String, ByVal lpWindowName As String) As Long
Private Declare Function FindWindowEx Lib "user32" Alias "FindWindowExA" (ByVal hWnd1 As Long, ByVal hWnd2 As Long, ByVal lpsz1 As String, ByVal lpsz2 As String) As Long
Private Declare Function GetDC Lib "user32" (ByVal hWnd As Long) As Long
Private Declare Function StretchBlt Lib "gdi32" (ByVal hdc As Long, ByVal x As Long, ByVal y As Long, ByVal nWidth As Long, ByVal nHeight As Long, ByVal hSrcDC As Long, ByVal xSrc As Long, ByVal ySrc As Long, ByVal nSrcWidth As Long, ByVal nSrcHeight As Long, ByVal dwRop As Long) As Long
Private Declare Function GetDesktopWindow Lib "user32" () As Long
Private Declare Function ReleaseDC Lib "user32" (ByVal hWnd As Long, ByVal hdc As Long) As Long
Private Declare Function apiGetWindow Lib "user32" _
Alias "GetWindow" _
(ByVal hWnd As Long, _
ByVal wCmd As Long) _
As Long
Private Declare Function apiGetClassName Lib "user32" _
Alias "GetClassNameA" _
(ByVal hWnd As Long, _
ByVal lpClassname As String, _
ByVal nMaxCount As Long) _
As Long

'Mouse position type
Private Type POINTAPI
x As Long
y As Long
End Type

'Private Const SRCCOPY = &HCC0020 ' (DWORD) dest = source
' handle identifies the child window at the top of the Z order,
' if the specified window is a parent window
Private Const GW_CHILD = 5
' Returns a handle to the window below the given window.
Private Const GW_HWNDNEXT = 2
Private Const MAX_LEN = 255
' class name for an Access form's client window
Private Const ACC_FORM_CLIENT_CLASS = "OFormSub"
' class name for the child window of an Access form's Client window
Private Const ACC_FORM_CLIENT_CHILD_CLASS = "OFEDT"
' Copies the source rectangle directly to the destination rectangle.
Private Const SRCCOPY = &HCC0020
' Maps pixels from the source rectangle into blocks of pixels in
' the destination rectangle. The average color over the destination block
' of pixels approximates the color of the source pixels.
Private Const STRETCH_HALFTONE& = 4
' Performs a Boolean AND operation using the color values for the
' eliminated and existing pixels. If the bitmap is a monochrome bitmap,
' this mode preserves black pixels at the expense of white pixels.
Private Const STRETCH_ORSCANS& = 2

Dim dsktp As Long, St As Long, PP As POINTAPI 'Some variables
Private Sub Detail_Click()
MsgBox Application.Forms("form1").hWnd
MsgBox Detail.Application.hWndAccessApp
End Sub

Private Sub Form_Load()
'this is modified code from "The Start Button Cam By Tomer Cohen:" & vbCrLf & vbCrLf & "http://come.to/Tomer-C", vbInformation, "Tomer Cohen"

Dim Wind As Long 'Temporary hwnd holder

'Finding the SystemTray Window (hwnd)
Wind = FindWindow("Shell_TrayWnd", "")

'Finding the Start Button Window (hwnd)
Wind = FindWindowEx(Wind, 0, "Button", vbNullString)

'Getting Start Button DC
' St = GetDC(Application.Forms("form1").hwnd)
St = GetDC(fGetClientHandle(Form_Form1))
'Getting the Desktop window hwnd
Wind = GetDesktopWindow()

'Getting the Desktop window DC
dsktp = GetDC(Wind)

'Timer1.Enabled = True
End Sub

Private Sub Form_Timer()
GetCursorPos PP

'Drawing the mouse's background on the Start Button
StretchBlt St, 0, 0, 480, 200, dsktp, PP.x - 30, PP.y - 12.5, 240, 100, SRCCOPY
End Sub

Private Sub Form_Unload(Cancel As Integer)
'Relesing the Start Button DC
ReleaseDC hWnd, St

'Releasing the Desktop Window DC
ReleaseDC hWnd, dsktp
End Sub

Function fGetClientHandle(frm As Form) As Long
' Returns a handle to the client window of a form
' An Access form's hWnd is actually bound to the
' recordselector "window"
'
Dim hWnd As Long

' get the first child window of the form
hWnd = apiGetWindow(frm.hWnd, GW_CHILD)

' iterate through all child windows of the form
Do While hWnd
' if we locate the client area whose class name is "OFormSub"
If fGetClassName(hWnd) = ACC_FORM_CLIENT_CLASS Then
' the Client window's child is a window with the class
' name of OFEDT, so just verify that we're looking at the
' right window
If fGetClassName(apiGetWindow( _
hWnd, GW_CHILD)) = _
ACC_FORM_CLIENT_CHILD_CLASS Then
' if we found a match, then return
' the handle and we're outta here.
fGetClientHandle = hWnd
Exit Do
End If
End If
' get a handle to the next child window
hWnd = apiGetWindow(hWnd, GW_HWNDNEXT)
Loop
End Function

Private Function fGetClassName(hWnd As Long) As String
Dim strBuffer As String
Dim lngCount As Long

strBuffer = String$(MAX_LEN - 1, 0)
lngCount = apiGetClassName(hWnd, strBuffer, MAX_LEN)
If lngCount > 0 Then
fGetClassName = Left$(strBuffer, lngCount)
End If
End Function