Conditional formatting prevents combobox dropdown on continuous form - vba

Question

The following code filters the dropdown list of a combobox in a continuous subform and allows the user to move up and down the dropdown to select data
'Move through the dropdown using up/down arrow keys
Private Sub IngCombo_KeyDown(KeyCode As Integer, Shift As Integer)
Dim MsgBoxResponse As String
Select Case KeyCode
'Tab button is pressed with "" in the field. Access returns a warning message if not dealt with
Case 9 'Tab Button
If Me.IngCombo.Text = "" Then
MsgBoxResponse = MsgBox("Ingredient you entered is not in the list" & vbCrLf & "Would you like to try again?", vbYesNo, "Ingredient not recognised")
Select Case MsgBoxResponse
Case Is = 6
KeyCode = 0
Case Is = 7
KeyCode = 0
Me.Undo
End Select
End If
Case vbKeyDown
Me.IngCombo.Selected(Me.IngCombo.ListIndex + 1) = True
KeyCode = 0
Me.IngCombo.DropDown
Case vbKeyUp
Me.IngCombo.Selected(Me.IngCombo.ListIndex - 1) = True
KeyCode = 0
Me.IngCombo.DropDown
Case vbKeyEscape
Me.IngCombo.Text = ""
Me.Undo
End Select
End Sub
Private Sub IngCombo_KeyUp(KeyCode As Integer, Shift As Integer)
'Filter dropdown to match what the user has typed
'This combo's control source is the IngredientID, but the ID is hidden, hence the SQL selects both the ID and Ingredient text
Dim UserText As String
If Len(Me.IngCombo.Text) > 0 Then
UserText = Me.IngCombo.Text
Me.IngCombo.RowSource = "SELECT IngredientsTbl.IngredientID, IngredientsTbl.Ingredient " _
& "FROM IngredientsTbl WHERE (((IngredientsTbl.Ingredient) LIKE '*" & UserText & "*'));"
If Me.IngCombo.ListCount > 0 Then
Me.IngCombo.DropDown
End If
Else
Me.IngCombo.RowSource = "SELECT IngredientsTbl.IngredientID, IngredientsTbl.Ingredient " _
& "FROM IngredientsTbl;"
End If
End Sub
Private Sub IngCombo_LostFocus()
Me.IngCombo.RowSource = "SELECT IngredientsTbl.IngredientID, IngredientsTbl.Ingredient " _
& "FROM IngredientsTbl ORDER BY IngredientsTbl.Ingredient;"
End Sub
'If user types string that is found by the 'Key Up' routine above but is in the middle of a string i.e. 'milk' is typed and 'buttermilk' is highlighted
'Then pressing tab results in the not in list error
Private Sub IngCombo_NotInList(NewData As String, Response As Integer)
MsgBox "No ingredient matches your search", vbOKOnly, "Nothing Found"
Me.IngCombo = ""
Response = acDataErrContinue
End Sub
This works as intended.
I then add a conditional format, [text19]>50, to the ‘IngCombo’ combobox. This also works as intended but changes the behaviour of the 'IngCombo' combobox. The dropdown no longer appears, and when the user types in the ‘IngCombo’ field of a new record, it has the effect of filtering the text in the ‘IngCombo’ field of the other records of the continuous form. Eg if the user types ‘mint’, then records that contain mint in ‘IngCombo’ are shown, but all the others are blank.
The word ‘calculating’ appears momentarily in the bottom left, replacing the words 'form view' after a key is pressed. I assume this is the conditional formatting doing its work and disrupting the code, as ‘calculating’ does not appear when there is no conditional formatting.
Is there a way of maintaining the functionailty of the code and also having the conditional formating
Update after June7's comment that referenced Allen Browne code.Tried moving code into a Private Sub that is called from the combo's Change event
Private Sub IngCombo_Change()
Dim Cmbo As ComboBox
Set Cmbo = Me.IngCombo
Dim NewText As String
NewText = Cmbo.Text
Call ReloadIngCombo(NewText)
End Sub
Private Sub ReloadIngCombo(UserText As String)
If Len(UserText) > 1 Then
Me.IngCombo.RowSource = "SELECT IngredientsTbl.IngredientID, IngredientsTbl.Ingredient " _
& "FROM IngredientsTbl WHERE (((IngredientsTbl.Ingredient) LIKE '*" & UserText & "*'));"
If Me.IngCombo.ListCount > 0 Then
Me.IngCombo.DropDown
End If
Else
Me.IngCombo.RowSource = "SELECT IngredientsTbl.IngredientID, IngredientsTbl.Ingredient " _
& "FROM IngredientsTbl;"
End If
End Sub
This works as intended. Adding a conditional format to the combobox prevents the dropdowns being shown to the user