Microsoft KB Archive/166100

= PPT97: Sample VB Code to Control Window Redraw =

Article ID: 166100

Article Last Modified on 10/11/2006

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APPLIES TO


 * Microsoft PowerPoint 97 Standard Edition

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This article was previously published under Q166100



SUMMARY
This article shows how to use the LockWindowUpdate API function in the SetSmallCaps macro to prevent PowerPoint from redrawing the application window. When the window is not locked you can see the fonts change as the macro runs. When the window is locked, this transition from normal text to small capital letters appears instantaneous. The macro unlocks the window before it finishes.

For more information about the SetSmallCaps macro, please see the following article in the Microsoft Knowledge Base:

163694 PPT: Sample Code to Apply Small Caps Formatting to Selection



MORE INFORMATION
Microsoft provides programming examples for illustration only, without warranty either expressed or implied. This includes, but is not limited to, the implied warranties of merchantability or fitness for a particular purpose. This article assumes that you are familiar with the programming language that is being demonstrated and with the tools that are used to create and to debug procedures. Microsoft support engineers can help explain the functionality of a particular procedure, but they will not modify these examples to provide added functionality or construct procedures to meet your specific requirements.

Overview of LockWindowUpdate API Function
To use the LockWindowUpdate function, you must have a handle (HWND) to the window you want to lock. The sample code uses the FindWindow API function to obtain a handle to the main application window: hwnd = FindWindow("PP97FrameClass", 0&) If FindWindow is successful, the variable hwnd (a long) holds a handle to the main application window. Now that you have a handle you can use the LockWindowUpdate function to prevent that window from redrawing: LockWindowUpdate (hwnd) To unlock the window you must call LockWindowUpdate with NULL (0&) as the parameter. LockWindowUpdate (0&) It is very important to add this statement. If your code locks a window and then fails to unlock it, the window stays locked even after your macro ends.

The Lock Window Version of the SetSmallCaps Macro
' API declarations for LockWindowUpdate and FindWindow. Declare Function LockWindowUpdate Lib "user32" _ (ByVal hwndLock As Long) As Long Declare Function FindWindow Lib "user32" Alias "FindWindowA" _ (ByVal lpClassName As String, ByVal lpWindowName As Long) As Long

Sub SetSmallCaps

' Used to trap errors. On Error Resume Next Err.Clear

' Dimension variables. Dim oTextRange As TextRange Dim oWordRange As TextRange Dim lNewFontSize As Long Dim i As Long Dim hwnd As Long

' Get a handle to the main application window. hwnd = FindWindow("PP97FrameClass", 0&)

' Lock the main applicationwindow. ' Prevents PowerPoint from redrawing the main window. LockWindowUpdate (hwnd)

' Get reference to the selected text. Set oTextRange = ActiveWindow.Selection.TextRange

' Check if error occurred getting text selection. If Err.Number <> 0 Then

MsgBox "Cannot apply Small Caps to selection. Please select " _ & "some text and run the macro again.", vbExclamation, _ "Invalid Selection"

' Stop the macro. End End If

' Loop through the words in the selection. For i = 1 To oTextRange.Paragraphs.Words.Count

' Get a reference to the first word in the selection. Set oWordRange = oTextRange.Paragraphs.Words(i, 1)

'With oWordRange.Paragraphs.Characters(1, 1) With oWordRange.Characters(1, 1)

' Set the first letter to be upper case. .ChangeCase ppCaseUpper

' Calculate the new font size. lNewFontSize = ((.Font.Size) / 1.3)

End With

' Change the remaining characters to the new font size. With oWordRange .Characters(2, (oWordRange.Length)).Font.Size = lNewFontSize .Characters(2, (oWordRange.Length)).ChangeCase ppCaseUpper End With

Next i

' Unlocks the main application window. Whenever you use the ' LockWindowUpdate API to lock a window, you must call ' LockWindowUpdate again (with a Null parameter 0&) to allow the ' window to redraw. LockWindowUpdate (0&)

End Sub

