Adjusting Screen Resolution Directly At Workbook Startup

[LoveCandle]

Hi everyone,

I have the following code to check Screen Resolution at workbook startup and change it directly to 1024 X 768 if it is not.

In addition to that, at workbook startup, I want to save the original Screen Resolution in the memory in order to reset Screen Resolution to it original setting before closing the program.

For that purpose I made some changes to the code (My changes work perfectly at workbook startup), but before closing the program, I receive a Compile error message says that (ByRef argument type mismatch),

Here is main code:
Option Explicit

Private Declare Function GetSystemMetrics Lib "user32.dll" (ByVal nIndex As Long) As Long
Const SM_CXSCREEN = 0
Const SM_CYSCREEN = 1

Private Const EWX_REBOOT = 2
Private Const CCDEVICENAME = 32
Private Const CCFORMNAME = 32
Private Const DM_BITSPERPEL = &H40000
Private Const DM_PELSWIDTH = &H80000
Private Const DM_PELSHEIGHT = &H100000
Private Const CDS_UPDATEREGISTRY = &H1
Private Const CDS_TEST = &H4
Private Const DISP_CHANGE_SUCCESSFUL = 0
Private Const DISP_CHANGE_RESTART = 1


Private Type typDevMODE
    dmDeviceName       As String * CCDEVICENAME
    dmSpecVersion      As Integer
    dmDriverVersion    As Integer
    dmSize             As Integer
    dmDriverExtra      As Integer
    dmFields           As Long
    dmOrientation      As Integer
    dmPaperSize        As Integer
    dmPaperLength      As Integer
    dmPaperWidth       As Integer
    dmScale            As Integer
    dmCopies           As Integer
    dmDefaultSource    As Integer
    dmPrintQuality     As Integer
    dmColor            As Integer
    dmDuplex           As Integer
    dmYResolution      As Integer
    dmTTOption         As Integer
    dmCollate          As Integer
    dmFormName         As String * CCFORMNAME
    dmUnusedPadding    As Integer
    dmBitsPerPel       As Integer
    dmPelsWidth        As Long
    dmPelsHeight       As Long
    dmDisplayFlags     As Long
    dmDisplayFrequency As Long
End Type

Private Declare Function EnumDisplaySettings Lib _
  "user32" Alias "EnumDisplaySettingsA" _
  (ByVal lpszDeviceName As Long, ByVal iModeNum As Long, _
  lptypDevMode As Any) As Boolean

Private Declare Function ChangeDisplaySettings Lib _
  "user32" Alias "ChangeDisplaySettingsA" (lptypDevMode As Any, _
  ByVal dwFlags As Long) As Long
  
Private Declare Function ExitWindowsEx Lib _
  "user32" (ByVal uFlags As Long, _
  ByVal dwReserved As Long) As Long


Public Function ChangeDisplayResolution(NewWidth As Long, _
   NewHeight As Long) As Boolean

'Usage:  ChangeDisplayResolution 800, 600

'Returns: True if succesful, false otherwise

'Comments:  Problems have been reported using this code for
'resolutions higher than 1024 X 768.  We recommend not using this
'snippet to go above this limit.


Dim typDM As typDevMODE
Dim lRet As Long
Dim iResp  As Integer

'typDM = pointer to info about current
'display settings

lRet = EnumDisplaySettings(0, 0, typDM)
If lRet = 0 Then Exit Function

' Set the new resolution.
With typDM
    .dmFields = DM_PELSWIDTH Or DM_PELSHEIGHT
    .dmPelsWidth = NewWidth
    .dmPelsHeight = NewHeight
End With

'Do the update -- Pass update structure to
'ChangeDisplaySettings API function
lRet = ChangeDisplaySettings(typDM, CDS_UPDATEREGISTRY)
Select Case lRet
Case DISP_CHANGE_RESTART

   iResp = MsgBox _
  ("You must restart your computer to apply these changes." & _
        vbCrLf & vbCrLf & "Restart now?", _
        vbYesNo + vbInformation, "Screen Resolution Changed")
    If iResp = vbYes Then
        ChangeDisplayResolution = True
        Reboot
    End If

Case DISP_CHANGE_SUCCESSFUL
    ChangeDisplayResolution = True
Case Else
    ChangeDisplayResolution = False
End Select

End Function

Private Sub Reboot()
    Dim lRet As Long
    lRet = ExitWindowsEx(EWX_REBOOT, 0)
End Sub

Sub VerifyScreenResolution(Optional Dummy As Integer)
     
    Dim x, y, MyA, MyB As Long
     
    x = GetSystemMetrics(SM_CXSCREEN)
    y = GetSystemMetrics(SM_CYSCREEN)
    MyA = x
    MyB = y
    If x = 1024 And y = 768 Then
    Else
    ChangeDisplayResolution 1024, 768
    End If
End Sub

And here is Workbook Open and Before Closing codes:

Private Sub Workbook_BeforeClose(Cancel As Boolean)

Dim MyA, MyB As Long

If MyA = "" And MyB = "" Then
Exit Sub
Else:
ChangeDisplayResolution MyA, MyB
End
End If

End Sub

Private Sub Workbook_Open()
VerifyScreenResolution
Application.WindowState = xlMaximized
End Sub

An other problem is that when the original Screen Resolution is 800 X 600, and after it is changed by the previous code to 1024 X 768, the workbook window is minimized and it is maximized automaticcly even after using the following line with Workbook_Open code:

Application.WindowState = xlMaximized

Can you please find me a solution for that and tell my what is wrong with my code?

Thanks a lot,

[shg]

MyA and MyB are locally declared in the Close event, and therefore always zero (and Longs are never equal to a null string).

If you want to retain values, declare them at the top of the module outside of any procedures.

If your code changed my screen resolution, it would have made its last appearance on my computer ...

[Leith Ross]

Hello LoveCandle,

Not all monitors support all resolution settings. There is a note in the code about this, albeit incomplete. API code can change from one version of Windows to other. If you plan to run this on multiple platforms, and distribute the code, you should add code to check the Windows version the code is running on before attempting to change any settings.

You may also run into problems running this if the computer has firewalls and/or anti-virus software. It may see the code as antagonistic. Unless you are an experienced programmer who is comfortable with low level language programming and interfacing, don't attempt to change the registry settings using the API. You can seriously damage your or someone else's computer.

[LoveCandle]

Hi,

Thak you both for your repleis and tips,

Mr. shg, I tried that but it didn't work with me, can you please try that by yourself and provide me with the code if it works,

Thak you,

[Obfuscated]

I have been reading many of these entries concerning screen resolution and have a question for "shg".

He/She said "If your code changed my screen resolution, it would have made its last appearance on my computer ...". I was wondering why?

If my code changed it to display the workbook in a format that it looks best / needs... and then changes it back to the original settings, why the concern?

[royUK]

I have been reading many of these entries concerning screen resolution and have a question for "shg".

He/She said "If your code changed my screen resolution, it would have made its last appearance on my computer ...". I was wondering why?

If my code changed it to display the workbook in a format that it looks best / needs... and then changes it back to the original settings, why the concern?

There's lways the chance that such cod, also code that hides Toolbars, etc, may not actually reverse at the end. This is more than annoying to users & really should be avoided

[Andy Pope]

If all you use is that application then not so bad. Although I too would be put off by something that messed with my settings to that extent.

What about all the other applications running on the pc. You will effect there size. Either making the windows too small or worse bigger, if the screen resolution is already higher.
How about somebody with eyesight such that they running their monitor at lower resolution?

Better to build your UI for a more conservative screen setting.