Storing Listbox Value Generated by a Row Source Query - database

Question

I am trying to store the value of a listbox (Actual_Polygon_Area) that has been generated via row source query. Each time I run the script my message box tells me that the value of the listbox is null and I suspect it's caused by the row source. The suspected listbox is named Actual_Polygon_Area and the field I am trying to store it in is Polygon_Area within the table FS_Actual_Polygon.
Private Sub Actual_Polygon_Save_Click()
If IsNull(Actual_Polygon_Year) Then
MsgBox "Please enter a year in which this polygon received treatment"
Actual_Polygon_Year.SetFocus
ElseIf IsNull(Actual_Polygon_Season) Then
MsgBox "Please enter the season in which this polygon received treatment"
Actual_Polygon_Season.SetFocus
ElseIf IsNull(Actual_Polygon_Treatment) Then
MsgBox "Please select the treatment type that was completed in this polygon."
Actual_Polygon_Treatment.SetFocus
ElseIf IsNull(Actual_Polygon_Notes) Then
MsgBox "Please write a short summary regarding treatment goals and objectives."
Actual_Polygon_Notes.SetFocus
ElseIf IsNull(Actual_Polygon_Area) Then
MsgBox "Polygon Area is null, please enter a value"
Actual_Polygon_Area.SetFocus
Else
Dim MyConnection As ADODB.Connection
Set MyConnection = CurrentProject.Connection
Dim rsFS_Actual_Polygon As ADODB.Recordset
Set rsFS_Actual_Polygon = New ADODB.Recordset
If IsNull(PolygonNo) Then
'add
rsFS_Actual_Polygon.Open "select * from FS_Actual_Polygon where PolygonNo= " & Actual_Polygon_ID & " and Treatment_Season= '" & Actual_Polygon_Season & "' and Treatment_Type= '" & Actual_Polygon_Treatment & "' and Project_Name = '" & Actual_Polygon_Project_Name & "' and Polygon_Area = " & Actual_Polygon_Area.Value & " and Treatment_Year = " & Actual_Polygon_Year, _
MyConnection, adOpenDynamic, adLockOptimistic
If Not rsFS_Actual_Polygon.EOF Then
MsgBox "The combination of Polygon ID, treatment-year, treatment-season, and treatment type already exist. Please check the combination."
Actual_Polygon_Year.SetFocus
Else
With rsFS_Actual_Polygon
.AddNew
![PolygonID] = Actual_Polygon_ID
![Project_Name] = Actual_Polygon_Project_Name
![Polygon_Area] = Actual_Polygon_Area.Value
![Treatment_Year] = Actual_Polygon_Year
![Treatment_Season] = Actual_Polygon_Season
![Treatment_Type] = Actual_Polygon_Treatment
![Polygon_Notes] = Actual_Polygon_Notes
.Update
End With
Actual_Polygon_Record.Requery
Actual_Polygon_New_Click
End If
I can post the rest of the code if necessary, I just didn't want to post a huge chunk.

Answer 1

You can use the .ItemsSelected and .ItemData methods to find and pass the value of the selected row from the listbox to your table.
This is a fairly typical use of the listbox control, and is a little easier than dealing with a multi-select control, but is still a bit cumbersome. You will need to create a For Each...Next loop to collect the row number of the selected row in your listbox and save to a variable. Then use that variable as the argument of the .ItemData method to return the bound column value for that selected row.
This MSDN article should have everything you need.
EDIT: While the above solution works for multi and single select listboxes, there is a more expedient way for single select listboxes:
Dim i as Integer
i = Me!Actual_Polygon_Area.ListIndex
If i = -1 Then
MsgBox "No item has been selected"
Exit Sub
End If
'Do above prior to `WITH` loop
...'Then in your `WITH` loop:
![Polygon_Area] = Actual_Polygon_Area.ItemData(i)