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MS Access: Enhanced Message Box Replacement

This project provides a custom and enhanced message box replacement for the default MsgBoxfound in Access. A Test database for Access 2007 is available at the bottom of this post. (Updated 12AUG2008.)

What’s wrong with the default MsgBox

The default message box in Access is sometimes useful to warn, inform or ask confirmation from the user.

It has, however, a few drawbacks:

• It is bland; the standard message box does not follow the currently selected Office 2007 scheme.
• The amount of text it can display is limited. If you try to display too much the text will be truncated.
• You can’t copy or save the content of the message being displayed.
• Because message boxes are viewed as intrusive, people tend not to read them and end-up closing them before they realize it may have contained useful information.
• It only displays plain text. You cannot format the message to draw attention to the key points.

Sometimes you need to display an important message or require users to take an action. Message boxes are not to be abused but they serve a useful purpose.

An enhanced message box

Rather than using the bland standard message box you can now have something a bit more customized.

Plain Text version of the enhanced custom message box under the Office Blue Colour Scheme:

RichText version of the enhanced custom message box under the Office Black Colour Scheme:

Here are the features of the enhanced message box:

• It is entirely compatible with the standard one: just change MsgBox to Box using find and replace should be enough.
• It allows the user to simply click on a button to copy the content of the message to the clipboard or to save it to a text file to a configurable default location.
• It looks and feel like it belongs to the main application, following its colour scheme.
• It attempts to prevent users from blindly closing the modal box without them making an effort to read the message: buttons will first be inactive for a configurable amount of time. It’s not a perfect solution, but it is quite effective.
• There is a RichBox version that can display rich HTML content, not just plain text, so important parts of the message can be formatted in a useful way.
• It is able to display large amount of data. While it’s not something you usually want, it may be useful for the message box to display more text in some situations (log or tracing information, legal documentation, etc).
• Rather than sprinkling your code with “& vbCrLf & _” uglies, you can embed newlines in the text itself by using C-style “n” escape sequences that will automatically be transformed into the appropriate newlines. Makes for clearer code and less typing.
• Because you get the source, you can easily customise the message box with new icons and colours to better match your overall application’s personality.
• It is non-blocking: if your application forces users to log-off after a certain amount of inactivity, the enhanced message box will just close rather than prevent Access from closing like the standard MsgBox does. Of course, it’s up to you to decide how to handle that gracefully, if at all.
• It properly displays the expected button captions based on the language of the operating system, so it behaves very much like the default MsgBox (for instance, it will properly display “Cancel” on English systems and “Annuler” on French ones).
• It also properly plays the system sounds associated with the type of message. You can also enable or disable the sound effect as needed.

How to use it

Download the demo below and copy (drag & drop) the following into your application:

• the FormDialog form,
• the API_GetTextMetrics module,
• the Dialog module.

If you rename the FormDialog, make sure you replace any occurrence to it in the code, in particular in the Dialog module.

Since the enhanced message box is just a replacement for the standard one, you just use it like you would use the MsgBox.
'----------------------------------------------------------------------------- ' Simple use of the Plaintext box ' Note the use of n that will be converted into a newline Dialog.Box "This is a plaintext message.nClick OK to dismiss", vbOKOnly+vbinformation, _ "Message Title" '----------------------------------------------------------------------------- ' Getting the result back Dim dr as vbMsgBoxresult dr = Dialog.Box("Are you sure you want to delete?", _ vbYesNoCancel+vbQuestion, "Confirm action") if (dr = vbYes) then DeleteRecords '----------------------------------------------------------------------------- ' Using named parameters Dialog.Box Prompt:="All your bases are belong to us", _ Buttons:=(vbOkOnly+vbCritical), _ Title:="Bad error" '----------------------------------------------------------------------------- ' Using the RichBox to display simple HTML ' The first line will be bold, then the word 'button' will be printed in red ' Here the n will be escaped to '<br/>' tags to simulate newlines. Dialog.RichBox "<strong>This is a bold message</strong>.n" & _ "Click the <font color=""#FF0000"">button</font> to dismiss.", vbOKOnly+vbinformation, _ "RichText Message Title" There are a few additional settings that can be used to change the behaviour of the enhanced message boxes.
One is that you can adjust the delay before the buttons become activated.
'----------------------------------------------------------------------------- ' Use the ButtonDelay to specify the time in seconds before the buttons become activated ' The default is 2s. Use 0 to activate the buttons immediately. Dialog.Box Prompt:="All your bases are belong to us", _ Buttons:=(vbOkOnly+vbCritical), _ Title:="Bad error", ButtonDelay:=1 '----------------------------------------------------------------------------- ' Change the default delay value. ' To disable the activation delay Dialog.DefaultButtonDelay = 0 ' To make the user wait 3 seconds before they can press any button Dialog.DefaultButtonDelay = 3 Another one is that you can enable or disable whether beeps should be played or not.
'----------------------------------------------------------------------------- ' Use AllowBeep to specify whether beeps should be played when the message box opens ' By default, they are. Dialog.Box Prompt:="All your bases are belong to us", _ Buttons:=(vbOkOnly+vbCritical), _ Title:="Bad error", AllowBeep:=false '----------------------------------------------------------------------------- ' Change the default behaviour. This is true by default. Dialog.DefaultAllowBeep = false The last settings is the folder where we should save the content of the message when the user clicks the Save button on the message box.
'----------------------------------------------------------------------------- ' Change the save folder. ' By default, the text messages will be saved in the same directory as the database. ' Here we want them to be saved to a temp directory Dialog.DefaultSavedTextFileFolder= "C:temp" These few settings make the enhanced message box more customizable.

Large text

The standard MsgBox cannot display much text. On the other hand, there is no real limitation to the amount of text the Box and RichBox can display.
When the amount of information is too much to fit the maximum allowed size for the message box the text will overflow and can be scrolled up/down as necessary.

Limitations of the RichBox

The RichBox version relies on the normal TextBox control’s ability under Access 2007 to display RichText wich is nothing more than lightweight HTML.
Because font size may be varying a lot in the message, it becomes very difficult to accurately predict the size of the box needed to display the whole message.
Short of implementing a complete HTML engine, we have to rely on some assumptions to display HTML.
The risk is that sometimes the content may not properly fit the TextBox control in some circumstances.
If you use the RichBox, thoroughly try displaying your messages and tweak the HTML as necessary to include additional lines or non-breaking spaces to ensure that the result looks good.
If you don’t overuse font size and don’t display in multiple fonts the RichBox should do the right thing most of the time.
Don’t overuse the RichBox to display colourful messages. There is a fine line between being informative and tasteless. Keep colours and formatting where it is useful.
I think that in most cases, the plain text version Box is more than enough.

How it works

The code makes extensive use of Win32 API calls.
Most of the hard work is done in the FomDialog class form. There is too much there to really go into the details but you are welcome to have a look at the commented code.
The code relies also on a utility function from Stephen Lebans used to calculate the size of of text. I have made some minor modification to that code so I would refer you to his original implementation if you are interested in calculating TextBox sizes for forms or reports.

In the code for the FormDialog, I re-implement some of the expected functionalities of the MsgBox: proper arrangement of the buttons, displaying of the appropriate icon, etc.
Once this is done, we calculate the size of the textbox needed to display the whole of the message.
In the case of RichText, we first use Application.PlainText() to convert the HTML into properly formatted plain text. We then calculate the Textbox size using a slightly larger font than needed as a way to ensure that the content of the RichText message will fit the box in most cases.
Once we know the size of the TextBox, we can easily resize the form to properly display the TextBox.
If there is too much text, we resize the form to its maximum permissible (70% or screen width and 90% of screen height) and change some of the visual cues to let the user know the text is overflowing.

One thing of note is the way the form is kept modal.
Rather than using DoCmd.OpenForm and DoCmd.Close I use the form as a class and create an instance manually (see the code in Dialog.Box and Dialog.Richbox). I keep this instance alive until I got the form’s result back.
If you are interested in knowing how the form is made modal, this is the code in FormDialog.ShowModal() what keeps the form open until the user clicks a button:
Public Function ShowModal() As VbMsgBoxResult ... ' Here we reset the result for the clicked button such as vbOK, vbYes, etc ' This is set in each Button's Click event m_Result = -1 ' Wait for the user to click a button Do While (m_Result = -1) DoEvents Sleep 50 Loop ShowModal = m_Result End Function The Sleep() function is a Win32 API that stops the current process for the given number of milliseconds. This in effects hands back the control to the Operating System for a short time. That way the system is still responsive and does not consume resources when it’s just waiting for user input.

Sample database

You can download a sample database containing all the necessary code as well as a number of tests.
This version only contains the database in Microsoft Access 2007 accdb format.

Download the EnhancedMsgBox01.zip (107KB), v1.1 containing the ACCDB database.

Code Updates

v1.1: 08AUG2008

• Corrected code for DefaultButtonDelay (thanks to Geoffrey) (was referencing wrong variable, causing self-referencing code).
• Corrected code for Box and RichBox to take the DefaultSavedTextFileFolder into account (the path was previously not passed onto the dialog boxes and the text file would always be created in the application folder instead of the one specified by DefaultSavedTextFileFolder)
• Added license notice at top of source code.

v1.0: 20MAY2008

• Original version

Resources

• Dissecting the MessageBox article on CodeProject
• TextWidth-Height code demo from Stephen Lebans (great resource, check it out!).
• Pixel to Twips conversion from MSDN.
• Copy Text to Clipboard from the excellent site The Access Web.
• Getting Resource Strings and more from DLLs.

This work is licensed under a Creative Commons Attribution 3.0 Unported License.
Free for re-use in any application or tutorial providing clear credit is made about the origin of the code and a link to this site is prominently displayed where end-users can easily access it.

27 comments May 20th, 2008

MS Access: Restarting the database programmatically

In my previous article about changing the MS Access colour scheme I had the need to allow the user to restart the database after the colour scheme was changed.
(Article and Code Updated 09AUG2008.)

Being able to cleanly restart the application is also useful in other instances:

• Changes made to the environment
• Recovering from errors (for instance after a network disconnection)
• Forcing the user to re-log cleanly into the application
• Automatically restarting a long-running application (for instance so that it may automatically compact on close and restart afresh with or without user intervention).

The problem is that you cannot -to the best of my knowledge- close and open again the same database from within MS Access itself.
Most executables cannot do that and the way to solve the issue is usually to pass the control to another boostrap programme, close the main application and let the bootstrap programme re-open the main application again.
I wanted a simple and clean way of using it. One that would not require shipping external programmes.

How to use it

Download the sample database below, copy the Utilities module or just the Restart sub defined in it into your own application.

To use it, just call the Restart sub and the application will close and re-open.
This will work for normal databases (mdb/accdb) and also compiled (mde/accde) and runtime (accdr) databases as well.

How it works

If you’re curious about the technical details, here is how it was put together.
The main idea is that the MS Access database application has to be self-sufficient and restart itself by performing these steps:

• create a small batch file
• run the batch file, passing the path and extension of our database
• close the main application
• the running batch file would wait for the MS Access lock file to be removed
• once the lock file disappears, we open the database

The key point here is that the batch file cannot just reopen the database right away: if the application is big or if it’s compacting on close for instance, it may take several seconds to actually close.
The only moment we can be pretty sure that the database is effectively closed is when the lock file is deleted by MS Access.

The batch file is hard-wired in the Restart sub that does all the work:
SETLOCAL ENABLEDELAYEDEXPANSION SET /a counter=0 :CHECKLOCKFILE ping 0.0.0.255 -n 1 -w 100 > nul SET /a counter+=1 IF "!counter!"=="60" GOTO CLEANUP IF EXIST "%~f1.%3" GOTO CHECKLOCKFILE start " " "%~f1.%2" :CLEANUP del %0 When the application runs the batch file, it passes 3 arguments:

• the full path to the database without the extension
• the database file extension without the leading “.”
• the appropriate database lock file extension (laccdb or ldb).

This allows us to easily construct the path to either the database or the lock file at line 07 and 08.
The funny use of PING is actually a simple way to wait for some time before we check if the lock file is still there or not. There is not SLEEP or WAIT function provided by default in Windows so we have to be a bit creative and use the time-out option of the PING command trying to ping an inexistent, but valid, IP address.
Once the lock file has disappeared, we open the database at line 80 and then delete the batch file itself so we leave no leftovers.

The other thing of note is that we now use a counter to keep track of the number of times we checked the existence of the lock file.
Once this counter reaches a pre-determined amount (60 by default, ~ 45 seconds) we consider that there is a problem and the database application didn’t close, so we just exit and delete the batch file.

Download the DatabaseRestart.zip (51KB) containing both an Access 2007 ACCDB and Access 2000 MDB test databases.

Code Updates

v1.1: 09AUG2008

• Now a separate test database (used to be bundled with the Colour Scheme sample).
• Added support for older Access versions (an Access2000 MDB is now included).
• Corrected wrong lock file extension for accd* files.
• Added a time-out feature after which the batch file will delete itself after a while if the Access lock file wasn’t released (for instance following a crash).
• Added checks to delete the batch file if it has not deleted itself for some reason (for instance after a reboot).
• The batch file now has a unique name based on the name of the database, allowing multiple databases to be restarted from the same directory.
• Added license notice at top of source code.
• Updated the article to reflect the changes.

v1.0: 06MAY2008

• Original version

This work is licensed under a Creative Commons Attribution 3.0 Unported License.

7 comments May 6th, 2008

MS Access: Changing the Color Scheme programmatically

Microsoft Office 2007 comes with 3 colour (color) schemes. Users can easily change it but when you deploy an Access application under the Runtime your users have no way to set the colour scheme as the application’s options are not available.

Luckily for us, Office 2007 stores the global colour scheme setting in the registry under: HKEY_CURRENT_USER\Software\Microsoft\Office\12.0\Common\Theme

The values being stored under that key are:

1. Blue scheme
2. Silver scheme
3. Black scheme

With this information, we can easily both read and set the colour scheme. The only caveat is that I could not find a way to notify Access to reload the setting automatically once it is changed, so users will have to restart the application before the change becomes active. A small price to pay but if anyone has a better idea, please let me know.

To write the new value to the registry I use a set of WIN 32 APIs that are more flexible than the default ones provided in VBA.

You can download the sample database as it contains all necessary files, including the definition for the Win32 API functions.

Download the ColorScheme.zip (31KB) containing the ACCDB database.

The sample also contains some code to restart the database. It will probably be the subject of a next post.

Improvements/uses:

• Find a way for Access to reload the settings without having to restart the application.
• Use the knowledge about the current scheme to change the other colour settings in the application (or even adapt the form’s theme).

References:

• Setting the BackColor to match the Office 2007 color scheme
• API Get / Set Registry functions from http://www.arcatapet.net/.

1 comment May 3rd, 2008

MS Access: Modal Dialogs with Transparent Backgrounds (redux)

Rob Cooper, of the Microsoft Access Team made an interesting post and a follow-up on how to add a transparent layer that cover the screen to focus the attention of the user to a login form or other important popup window.

The trick is to use some WIN 32 API calls to modify the transparency of a standard MS Access form made to cover the screen.

The effect is quite neat and I thought I would try it and make a sample database for others to tinker with it.
My version allows you to chose between covering the whole screen or just the main Access window and it will test if it’s running under a Remote Desktop Terminal and disable the layer in that case.

Update 07MAY2008

Following Rob’s improvements I made another sample database that incorporates his code with a few improvements:

• I added the LightBoxForm.LayerToFullScreen property so users can choose explicitly how they want the layer to be shown.
• I moved the code to hide the layer into a Hide() sub so you can just show/hide the layer using LightboxForm.Show and LightboxForm.Hide.
• I changed the Form’s Resize event code in the LightBoxForm class to avoid flickering: resizing the form within its Resize event actually trigger the Resize event again a second time which causes flickering.
  I simply modified the code to make the form totally transparent (opacity of 0) the first time the event is fired and assign it the expected opacity when the event handler in re-entered.

'----------------------------------------------------------------------------- ' Handle the Layer Form Resize event '----------------------------------------------------------------------------- Private Sub m_objForm_Resize() Static busyResizing As Boolean Dim lngStyle As Long Dim r As RECT ' disable screen updates m_objForm.Painting = False ' When the form opens initially, we make it totally transparent to avoid flickering lngStyle = GetWindowLong(m_objForm.hWnd, GWL_EXSTYLE) SetWindowLong m_objForm.hWnd, GWL_EXSTYLE, lngStyle Or WS_EX_LAYERED SetLayeredWindowAttributes m_objForm.hWnd, 0, 0, LWA_ALPHA ' If the Access window is maximized, then maximize the lightbox form. ' If the Access window is not maximized, then ' position the lightbox form so that it covers the Access window If IsZoomed(hWndAccessApp()) Or m_bLayerToFullScreen Then DoCmd.Maximize Else GetWindowRect Application.hWndAccessApp(), r MoveWindow m_objForm.hWnd, r.x1, r.y1, (r.x2 - r.x1), (r.y2 - r.y1), True End If If busyResizing Then ' Get the current window style, then set transparency lngStyle = GetWindowLong(m_objForm.hWnd, GWL_EXSTYLE) SetWindowLong m_objForm.hWnd, GWL_EXSTYLE, lngStyle Or WS_EX_LAYERED SetLayeredWindowAttributes m_objForm.hWnd, 0, (m_sngOpacity * 255), LWA_ALPHA ' enable screen updates m_objForm.Painting = True ' Back to normal busyResizing = False Else busyResizing = True End If End Sub

Samples

There are now 2 sample databases. Ech zip contains a Microsoft Access 2007 ACCDB file and its conversion to Access 2000¹ and Access 2002-2003 MDB but please note that I have not been been able to test those in older version of Access and that form transparency doesn’t work in Operating Systems older than Windows 2000.

Download TransparentLayer02b.zip (138KB), recommended version
(improved, more flexible version, based on Rob’s updated article).

Download TransparentLayer01b.zip (122KB), original version
(simple code, based Rob’s original article).

Troubleshooting

• If you are getting security warnings: make sure that you open the database from a Trusted Location or you will receive a security prompt. If you don’t know how to do that, check these steps.
• If the layer appears on top of the login form instead of behind: make sure that the top-most form has ist Modal properties set to Yes and the frmLightBox form has its modal property set to No.
  If you improve on it, please let me know and I’ll post it here for all to find.

12 comments May 1st, 2008