Which is preferred way to toggle display of Form?

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Howard Kaikow - 30 Dec 2004 12:15 GMT

I am using SetWindowPos to cause a Form to always appear on top.

However, the program displays Word Dialog boxes, which are then covered,
entirely or partially, by the Form.

I've though of the following solutions:

1. Hide, then Show the Form.
2. Change the WindowState to minimize, then display the Form.
3. Use SetWindowState to change the Z-order using HWND_BOTTOM and HWND_TOP.

The drawback to Hide/Show is that I have to have the code remember whether
use vbModeless or vbModal. If I use .Visible to Hide/Show the Form, does
.Visible = True remember whether the Form was previously shown with
vbModeless or not?

Which of he above methods is preferred?
Is there a better way?

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http://www.standards.com/; See Howard Kaikow's web site.

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Randy Birch - 30 Dec 2004 16:27 GMT

#3, though I'd probably just turn off the topmost rather than set it to the
bottom.

Signature

Randy Birch
MS MVP Visual Basic
http://vbnet.mvps.org/

:I am using SetWindowPos to cause a Form to always appear on top.
:
[quoted text clipped - 14 lines]
: Which of he above methods is preferred?
: Is there a better way?

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Howard Kaikow - 30 Dec 2004 22:47 GMT

I meant SetWindowsPos, not SetWindowsState.

Best I've been able to do so far with SetWindowsPos is minimize the Form,
but that seems better using WindowsState.

Bye thee waye, I tried constructing a simplified example demomstrating the
issue I raised.

I used a standard VB project and automated Word.
I found that the problem does not occur in a standard project, only when the
code is run via a DLL.
In a standard project, the Word Dialog appears on top of the Form, even tho
the Form is set to be on top.

The following is the code in the Form.

Private Sub btnByeBye_Click()
Unload Me
End Sub

Private Sub Form_Activate()
'Set the window position to topmost
SetWindowPos Me.hWnd, HWND_TOPMOST, 0, 0, 0, 0, _
SWP_NOACTIVATE Or SWP_SHOWWINDOW Or SWP_NOMOVE Or SWP_NOSIZE
End Sub

The following is the startup code

Public Const HWND_BOTTOM As Long = 1
Public Const HWND_NOTOPMOST = -2
Public Const HWND_TOPMOST = -1
Public Const SWP_HIDEWINDOW As Long = &H80
Public Const SWP_NOACTIVATE = &H10
Public Const SWP_NOMOVE = &H2
Public Const SWP_NOSIZE = &H1
Public Const SWP_SHOWWINDOW = &H40
Public Declare Sub SetWindowPos Lib "User32" (ByVal hWnd As Long, ByVal
hWndInsertAfter As Long, _
ByVal X As Long, ByVal Y As Long, ByVal cx As Long, ByVal cy As
Long, ByVal wFlags As Long)

Public Sub Main()
Dim appWord As Word.Application

Set appWord = New Word.Application
With frmSetWindowPos
.Show vbModeless
' .WindowState = vbMinimized
With appWord
With .Dialogs(Word.wdDialogFileOpen)
.addtomru = False
If .Display = -1 Then
MsgBox .Name
End If
End With
.Quit
End With
' .WindowState = vbNormal
End With
Set appWord = Nothing
End Sub

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Howard Kaikow - 31 Dec 2004 12:49 GMT

I've constructed a simple example of how to reproduce the problem.

First, put the following in a Word template:

Public Sub RunTest()
Dim cls As clsTestOnTop
Set cls = New clsTestOnTop
With cls
.SetClass Word.Application
.TestOnTop
End With
End Sub

Next, create an ActiveX DLL with the following:

A module that has:

Public gappWord As Word.Application

Public Const HWND_BOTTOM As Long = 1
Public Const HWND_NOTOPMOST = -2
Public Const HWND_TOPMOST = -1
Public Const SWP_HIDEWINDOW As Long = &H80
Public Const SWP_NOACTIVATE = &H10
Public Const SWP_NOMOVE = &H2
Public Const SWP_NOSIZE = &H1
Public Const SWP_SHOWWINDOW = &H40
Public Declare Sub SetWindowPos Lib "User32" (ByVal hWnd As Long, ByVal
hWndInsertAfter As Long, _
ByVal X As Long, ByVal Y As Long, ByVal cx As Long, ByVal cy As
Long, ByVal wFlags As Long)

A class named clsTestOnTop that has:

Public WithEvents appWord As Word.Application

Public Sub TestOnTop()
frmSetWindowPos.Show vbModeless
End Sub

Public Sub SetClass(appIs As Word.Application)
Set appWord = appIs
Set gappWord = appIs
End Sub

Friend Property Get WordApp() As Word.Application
Set appWord = WordApp
Set gappWord = appWord
End Property

Friend Property Set WordApp(ByVal appNew As Word.Application)
Set appWord = appNew
Set gappWord = appWord
End Property

Private Sub Class_Terminate()
Set appWord = Nothing
End Sub

A Form named frmSetWindowPos that is made large enough to cover a good
portion of the screen, and has two buttons, with the following code:

Private Sub btnByeBye_Click()
Unload Me
End Sub

Private Sub btnRunMe_Click()
' Me.WindowState = vbMinimized
With gappWord
With .Dialogs(Word.wdDialogFileOpen)
.addtomru = False
If .Display = -1 Then
MsgBox .Name
End If
End With
End With
' Me.WindowState = vbNormal
End Sub

Private Sub Form_Activate()
'Set the window position to topmost
SetWindowPos Me.hWnd, HWND_TOPMOST, 0, 0, 0, 0, _
SWP_NOACTIVATE Or SWP_SHOWWINDOW Or SWP_NOMOVE Or SWP_NOSIZE
End Sub

Private Sub Form_Terminate()
Set gappWord = Nothing
End Sub

Now, add a reference to the class in the Word project.
Run the code.

You should see the Form on top of the Word Dialog, if you made the Form
large enough.
Next, uncomment the two WindowState statements in the Form.

Now, when you run the code, the Word dialog will not be covered and the Form
will re-appear.

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Howard Kaikow - 31 Dec 2004 14:23 GMT

I have found a way to reproduce the problem using an EXE, as well as the
previously posted example of using a DLL.

The problem occurs because the Word Dialog is invoked from within the VB
Form, DLL or EXE matters not.

To reproduce the problem, create a standard VB EXE project with the
following:

A module with:

Public appWord As Word.Application
Public Sub Main()
Set appWord = New Word.Application
frmSetWindowPos.Show vbModeless
End Sub

A Form, large enough to be annoying, with:

Option Explicit
Private Const HWND_BOTTOM As Long = 1
Private Const HWND_NOTOPMOST = -2
Private Const HWND_TOPMOST = -1
Private Const SWP_HIDEWINDOW As Long = &H80
Private Const SWP_NOACTIVATE = &H10
Private Const SWP_NOMOVE = &H2
Private Const SWP_NOSIZE = &H1
Private Const SWP_SHOWWINDOW = &H40
Private Declare Sub SetWindowPos Lib "User32" (ByVal hWnd As Long, ByVal
hWndInsertAfter As Long, _
ByVal X As Long, ByVal Y As Long, ByVal cx As Long, ByVal cy As
Long, ByVal wFlags As Long)

Private Sub btnByeBye_Click()
Unload Me
appWord.Quit
Set appWord = Nothing
End Sub

Private Sub btnRunMe_Click()
' Me.WindowState = vbMinimized
With appWord
With .Dialogs(Word.wdDialogFileOpen)
.addtomru = False
If .Display = -1 Then
MsgBox .Name
End If
End With
End With
' Me.WindowState = vbNormal
End Sub

Private Sub Form_Activate()
'Set the window position to topmost
SetWindowPos Me.hWnd, HWND_TOPMOST, 0, 0, 0, 0, _
SWP_NOACTIVATE Or SWP_SHOWWINDOW Or SWP_NOMOVE Or SWP_NOSIZE
End Sub
Make th emodule the startup object.

When you run the code, you will need to use Alt Tab to ge taccess to the
Word dialog.

If you uncomment the WindowState statements, then the Form gets minimized
out of the way.

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VB Forum / General / December 2004

Which is preferred way to toggle display of Form?