New to VBA - Textbox/ List question

[dreamnauta]

Hi everyone,

I decided to begin learning access vba to make my databases more user friendly/interactive to non-access users. Here is a picture of the controls on my form: http://imageshack.us/photo/my-images/683/35819300.png/



The idea is when a user enters a CIP number in the 'Add CIP' Field, an add will occur to the listbox as well.

Here is my first function:

 
Private Sub listBoxPopulate()
Dim strTextInput As String
Dim textInput As Integer
 
strTextInput = Text45.Text
 
If strTextInput <> Null Then
textInput = CInt(strTextInput)
List43.Add (textInput)
 
End If
End Sub

When I try to compile it says access is missing an object reference. Now to use the text property it says I have to give the box focus. How do I do this?

- Josh

[pbaldy]

There are a few things to work on.

For starters, the focus error is because you use the .Text property. You want the .Value property, which is the default. You can't test for Null that way. You could use the IsNull() function. That said, a String variable can never be Null (it could be a zero length string: ""). I might test with IsNumeric, since that appears to be your end goal.

I personally rarely use Value List for list or combo boxes, I typically have a table that stores the options. That means I'd be adding a record to the underlying table and doing a Requery on the listbox. However, I think to add an item to a Value List the method is AddItem, not Add.

Let's see where that gets us.

[dreamnauta]

Thanks Paul, you were very helpful!

[dreamnauta]

There seems to be a problem compiling due to "missing reference object".
What am I doing wrong? Any help appreciated.

P.S. I have programmed in a variety of languages, so i'm not completely new to programming. I read through Access 2010 VBA Macro Programming by Richard Shephard which was a good overview.

 
Private Sub listBoxPopulate()
Dim strTextInput As String
Dim textInput As Integer
 
//error in this line
strTextInput = Text45.Value 
 
If strTextInput = IsNumeric(strTextInput) Then
textInput = CInt(strTextInput)
List43.AddItem (textInput)
End If
End Sub
 
Private Sub Command52_Click()
listBoxPopulate
End Sub

[pbaldy]

That's an odd error, though I suspect I know what is causing it. The "Me" keyword is your friend, as it provides a shortcut to refer to whatever object the code is in (ie the form or report). It will give you Intellisense as soon as you type "Me.", which will help make sure you don't misspell object names. Try

strTextInput = Me.Text45.Value

which presumes Text45 is a textbox with a value in it (note that a String variable can't take a Null, so that will error if the textbox is Null). This test won't work:

If strTextInput = IsNumeric(strTextInput) Then

IsNumeric() will return a Boolean, ie either True or False (the value tested is either numeric or not). I'd use a test like:

If IsNumeric(strTextInput) Then
  'do what you want with a numeric input
Else
  'warn the user the input wasn't valid
End If

[dreamnauta]

Thanks for all the help. My error was in referencing a 'outside' form.

Here is the correct code for reference:

 
Public Sub listBoxPopulate()
    Dim strTextInput As String
    Dim textInput As Long
   
    strTextInput = Forms!Enrollment_GUI!inputTextBox.Value
    
    If IsNumeric(strTextInput) Then
        textInput = CLng(strTextInput)
        Forms!Enrollment_GUI!listBox.AddItem (textInput)
    Else
       MsgBox ("Please enter numeric data")
    End If
End Sub
Public Sub Command52_Click()
       listBoxPopulate
End Sub

Thanks again!

[pbaldy]

Happy to help!