I'm working in Excel 2010 VBA. Is there a way of accessing values in global variables declared outside a userform, in code inside the userform? Code inside my userform returns the global variable as null - can't work out why!
The variable is declared in the ThisWorkbook module as:
Public TargetCell As Range
Public TargetCellWorksheet as Worksheet
Public CurrentValue As Long
Inside the userform, I have this code on the "Update" button:
Private Sub Update_Click()
MsgBox ("Start of Update sub. TargetCellWorksheet =" & TargetCellWorksheet)
End Sub
The msgbox returns "" for the variable.
Hoping someone may be able to help me understand this and how to access the variable inside the userform? Thank you in advance
As for the problem itself, you declare
Public TargetCellWorksheet as Worksheet
and then try to show it into a MsgBox:
MsgBox ("Start of Update sub. TargetCellWorksheet =" & TargetCellWorksheet)
Did you maybe mean TargetCellWorksheet.Name, or TargetCellWorksheet.Range("A1").Value, since the MsgBox expects to receive a string?
However, if you're sure about your code, it might depend on the fact that the variable is not properly declared as Public and it goes at module level only. You might want to add a property to your form, if the variable is part of the form itself (I assume that you meant to use CurrentValue, but you can simply change the type of the property from Long to Worksheet and use it instead):
This goes inside the code of your form
Dim pCurrentValue As Long
Public Property Get CurrentValue() As Long
CurrentValue = pCurrentValue
End Property
Public Property Let CurrentValue (value As Long)
pCurrentValue = value
End Property
Hence, passing the variable from the module to the form like this:
This goes into your module, before you enter the code of the form
Dim myForm As New yourForm
myForm.CurrentValue = whateverYourVariableIs
and so using the variable inside your form like this:
You can hence use your variable by calling it from the property of the form
myVariableInTheForm = Me.CurrentValue
I must say that, however, it is strange that a public variable is not reaching the stack of the form. Are you sure you're not only declaring the variable without assigning any value before?
Related
In VBA, is there any known mechanism to fool the compiler into allowing the use of reserved keywords as names for class properties? For example, I would like to create a property called Select in one of my class modules. However, the compiler flags my declaration as an error. Below is the syntax I used:
Public Property Get Select() As Database.SQLStatements
End Property
Database is my VBA project name and SQLStatements is one of the class modules I created. Also, I'm running the code in MS Access 2010.
You can do that and use any keyword/reserved word in your VBA. But then it will make your code a lot messy and very hard to read/debug/maintain.
If you have a bool property named If in your class you will end up with something like this If .If Then, well, good luck reading that. Also code maintenance like Find/Replace/rename etc. will need extra caution and more work.
Anyhow, if you are willing to go through all this pain, here is how you do it.
After the keywords/reserved words add a invisible blank space using ALT+0160 and that's it. VBA will consider it a perfectly legal name. e.g. If .
Also, you will have to either use intellisense for using these propertynames or manually type the altcode everywhere. That's extra typing.
clsTest
Option Explicit
Private m_sSelect As String
Private m_bIF As Boolean
Public Property Get Select () As String '~~> Select () is actually typed as SelectALT+0160()
Select = m_sSelect
End Property
Public Property Let Select (ByVal sNewValue As String)
m_sSelect = sNewValue
End Property
Public Property Get If () As Boolean
If = m_bIF
End Property
Public Property Let If (ByVal bNewValue As Boolean)
m_bIF = bNewValue
End Property
Test Module
Option Explicit
Sub demo()
Dim objTestClass As clsTest
Set objTestClass = New clsTest
With objTestClass
.Select = "It works. But it will, for sure, create readibility/maintenance issues."
.If = False
End With
MsgBox objTestClass.Select
'/ See how hard it will to read/debug this sort of code
With objTestClass
If .If Then '~~> This line here :)
MsgBox "If prop value is TRUE"
Else
MsgBox "If prop value is FALSE"
End If
End With
End Sub
ALT+0160 <> Space
My obstacle is trying to get multiple subs to recognize class variables. When I try to declare them globally, I get a compile error: "Invalid outside procedure". Then, when I run a public function or sub to declare the variables, they remain undefined in the other subs. I want multiple subs to recognize the variables because their values are supposed to be altered via UserForm, and then utilized in a different sub.
If it could work in this manner, great, but I understand that my design could fundamentally be flawed. Please advise!
This is my Class definition, inserted as a Class module named "cRSM":
Option Explicit
Private pName As String
Private pDesiredGrowth As Double
'Name of RSM
Public Property Get Name() As String
Name = pName
End Property
Public Property Let Name(Value As String)
pName = Value
End Property
'Growth property
Public Property Get DesiredGrowth() As Double
DesiredGrowth = pDesiredGrowth
End Property
Public Property Let DesiredGrowth(Value As Double)
If Value > 0 And Value < 1 Then
pDesiredGrowth = Value
End If
End Property
This is invalid procedure error (which I put in the Global Declarations section):
'Bedoya
Dim Bedoya As cRSM
Set Bedoya = New cRSM
Bedoya.Name = "Bedoya"
And this is the "variable not defined error" (within a private sub):
Private Sub Add_Click()
**Bedoya.DesiredGrowth** = Txt2.Value
Thank you for your time
In a standard module (I name mine MGlobals), put
Public Bedoya As cRSM
Then in another standard module (I name mine MOpenClose), put
Sub Initialize()
If Not Bedoya Is Nothing Then
Set Bedoya = New cRSM
End If
End Sub
Any default properties you want set should be set in the Class_Initialize procedure. In any procedure that you want to use Bedoya, use
Initialize
and it will instantiate the global variable if necessary. The only difference between this and the New keyword is that you can't accidentally instantiate the variable with this method. You either call Initialize or you don't. A lot of VBA developers use New, but almost never do for that reason.
If I understood well You want a global object.
You can put the declaration in module like
public Bedoya As cRSM
then you have create the object ... you can use a global event inside the Workbook like
Private Sub Workbook_Open()
Set Bedoya = New cRSM
Bedoya.initialize("Bedoya") 'a method to initialize private variables
End Sub
Now you can use the global object. You have to restart the excel file or run this method manually.
Is not good style to use global variables, but sometimes is the more easy to do :P
What you want to do nowadays is done using singleton Software Pattern, but this is for other day hehehe
I am developing an Excel (2010+) Application using VBA and have run into an issue where the AfterRefresh event function is not being invoked once the query finishes executing.
I have not been able to find many decent resources or documentation for how to have this event function triggered in a Class Module. I decided to use the Class Module design route instead of putting the event handlers in the worksheet after receiving a response to an earlier question about QueryTables (found here Excel VBA AfterRefresh).
Here is the code for my Class Module called CQtEvents
Option Explicit
Private WithEvents mQryTble As Excel.QueryTable
Private msOldSql As String
' Properties
Public Property Set QryTble(ByVal QryTable As QueryTable): Set mQryTble = QryTable:
End Property
Public Property Get QryTble() As QueryTable: Set QryTble = mQryTble:
End Property
Public Property Let OldSql(ByVal sOldSql As String): msOldSql = sOldSql:
End Property
Public Property Get OldSql() As String: OldSql = msOldSql:
End Property
Private Sub Class_Initialize()
MsgBox "CQtEvents init"
End Sub
' Resets the query sql to the original unmodified sql statement
' This method is invoked when the Refresh thread finishes executing
Private Sub mQryTble_AfterRefresh(ByVal Success As Boolean)
' Problem is here
' This function is never called :( Even if the query successfully runs
Me.QryTble.CommandText = Me.OldSql
End Sub
Here is a quick snapshot of the code the creates an instance of this class, finds a relevant QueryTable, then calls Refresh
Option Explicit
Sub RefreshDataQuery()
'Dependencies: Microsoft Scripting Runtime (Tools->References) for Dictionary (HashTable) object
'From MGLOBALS
cacheSheetName = "Cache"
Set cacheSheet = Worksheets(cacheSheetName)
Dim querySheet As Worksheet
Dim interface As Worksheet
Dim classQtEvents As CQtEvents
Set querySheet = Worksheets("QTable")
Set interface = Worksheets("Interface")
Set classQtEvents = New CQtEvents
Dim qt As QueryTable
Dim qtDict As New Scripting.Dictionary
Set qtDict = UtilFunctions.CollectAllQueryTablesToDict
Set qt = qtDict.Item("Query from fred2")
''' Building SQL Query String '''
Dim sqlQueryString As String
sqlQueryString = qt.CommandText
Set classQtEvents.QryTble = qt
classQtEvents.OldSql = sqlQueryString ' Cache the original query string
QueryBuilder.BuildSQLQueryStringFromInterface interface, sqlQueryString
' Test message
MsgBox sqlQueryString
qt.CommandText = sqlQueryString
If Not qt Is Nothing Then
qt.Refresh
Else
' ... Error handling code here...
End If
''' CLEAN UP '''
' Free the dictionary
Set qtDict = Nothing
End Sub
Also here is a screenshot of the Module structure http://imgur.com/8fUcfLV
My first thought on what might be the issue was passing the QueryTable by value. I am not the most experienced VBA developer, but I reasoned this would create a copy and be calling the event on an unrelated table. However, this was not the case and passing by Reference did not fix the problem either.
Also the query is confirmed to run successfully as the data is correctly showing up and being refreshed.
EDIT
I added the BeforeRefresh event function to CQtEvents class Module and confirmed this function is called once Refresh is called
Private Sub mQryTble_BeforeRefresh(Cancel As Boolean)
MsgBox "Start of BeforeRefresh"
End Sub
How might I alter this code get my QueryTable from the QTableModule's RefreshDataQuery() Sub routine to have the AfterRefresh function invoked when the query is successfully ran?
How to catch the AfterRefresh event of QueryTable?
Explanation: in your situation, before event was fired you lost reference of your QueryTable by setting it to nothing when you made cleaning or procedure ended.
General solution: you must be sure that your code is still running and/or you need to keep any references to your QueryTable.
1st solution. When calling QT.Refresh method set the parameter to false in this way:
qt.Refresh false
which will stop further code execution until your qt is refreshed. But I don't consider this solution to be the best one.
2nd solution. Make your classQtEvents variable public and after RefreshDataQuery sub is finished check the status with some other code.
in you CQtEvents class module add the following public variable:
Public Refreshed As Boolean
in your BeforeRefresh event add this:
Refreshed = False
in your AfterRefresh event add this line of code:
Refreshed = True
Make your classQtEvents variable declaration public. Put this before Sub RefreshDataQuery()
Public classQtEvents as CQtEvents
but remove appropriate declaration from within your sub.
Now, even your sub is finished you will be able to check status of refreshment by checking .Refreshed property. You could do it in Immediate or within other Sub. This should work for Immediate:
Debug.Print classQtEvents.Refreshed
3rd solution. (a bit similar to 1st one) Follow steps 1 to 3 from 2nd solution. After you call qt.Refresh method you could add this loop which will stop further code execution until qt is refreshed:
'your code
If Not qt Is Nothing Then
qt.Refresh
Else
' ... Error handling code here...
End If
'checking
Do Until classQtEvents.Refreshed
DoEvents
Loop
Final remark. I hope I didn't mixed up qt variable with classQtEvents variable. I didn't tried and tested any solution using your variables but wrote all above with referenced to code I use.
A github repo that demonstrates the minimum code needed to get this working can be found here.
As mentioned, if your event handler isn't in scope, or your QueryTable reference is lost, you won't catch the event. The key factors to ensuring you catch the event are:
Declare a global variable of your event-handling class module's type outside of any subroutines/methods, at the top of a file (I chose the ThisWorkbook file).
Add a Workbook_Open event handler and instantiate that variable there, so that it is available immediately and will remain in scope (since it's global).
At that point, or at any downstream point when you have a QueryTable you're interested in, pass that QueryTable to the global instance to wire up its events.
(It took me a couple tries to figure this out myself, when someone pointed me in this direction as an answer to this question.)
I've created the instance "Lassie" of the class "Dog" within a particular sub in my program. I have also given it some useful properties, such as Lassie.Age = 7 and Lassie.HeelCapability = False.
Now I would like to access another sub and change the Lassie.HeelCapability to True.
How do I go about defining the instance "Lassie" within this new sub so it can be worked with?
All the code I have come accross goes like this:
Dim Lassie As classDog
Set Lassie = New classDog
Essentially what I am looking for is a way to import the existing instance "Lassie" into another sub, without using the keyword "New" and thereby creating a new "Lassie" (without all the properties previously given).
The errormessages I have been receiving tell me either "object required" or "object variable or with block variable not set".
Surely there is a way to do this.
Thanks in advance.
You will need to pass 'Lassie' as a parameter to your other sub.
public sub DeclareSub()
Dim Lassie as classDog
Lassie = new classDog
OtherSub Lassie
end sub
public sub OtherSub(ByRef dog as classDog)
end sub
The variable 'dog' in the subroutine 'OtherSub' refers to the same object instance as the variable 'Lassie' from 'DeclareSub'.
Pass the object in ByRef to your new Subroutine.
Sub ChangeHeel(ByRef olassie As classDog)
'change the object here, and it will be changed in the calling sub
olassie.HeelCapability = True
End Sub
In my previous question, How do I assign a value to a property where the property name is supplied at runtime in VBA?, I learned to use CallByName to set a property in a class at run time.
This time, however, I'm trying to figure out how to get an object at run time from a string.
For example, let's say I have a string with the following data: Worksheets("RAW DATA").Range("A1").QueryTable.
Here's what I might try to do where the data above is the input for strParam below:
Function GetObject(strParam As String) As Object
GetObject = SomeFunction(strParam)
End Function
In this case, GetObject should return a QueryTable when evaluated against Worksheets("RAW DATA").Range("A1").QueryTable. Is there anything in VBA that could take the place of SomeFunction from the example above?
Active Scripting Engine can help you. Instantiate ScriptControl ActiveX, use .AddObject() method to add reference to Excel's Application object to the script control's execution environment, set the third parameter to True to make all Application's members accessible too. Then just use .Eval() method to evaluate any property or method, which is the Application's member. The example below shows evaluation of Worksheets() property:
Sub TestQueryTable()
Dim objQueryTable As QueryTable
Dim strEvalContent As String
strEvalContent = "Worksheets(""RAW DATA"").Range(""A1"").QueryTable"
Set objQueryTable = EvalObject(strEvalContent)
objQueryTable.Refresh
MsgBox objQueryTable.Connection
End Sub
Function EvalObject(strEvalContent As String) As Object
With CreateObject("ScriptControl")
.Language = "VBScript"
.AddObject "app", Application, True
Set EvalObject = .Eval(strEvalContent)
End With
End Function
If you are on 64-bit Office, this answer may help you to get ScriptControl to work.
This time you're out of luck. There is no VBA equivalent of eval (not in Excel anyway...there is in Access VBA).
(Application.Evaluate() evaluates strings as Excel expressions, not as VBA code.)
There's the "Evaluate" method (or [ ] brackets). I don't think it will do exactly what you expect - as in run VBA code found in a string. You can look it up in the VBA help menu.