Class Module codes for Change Event of comboboxes

Question

I have a userform where I put 10 rows of comboboxes for 7 columns. Which means I got 70 comboboxes altogether. To ease your understanding, I will refer the first combobox as (1,1) for (row,column).

What am I trying to do is, when a user input values on any combobox on Row 1, I want the values to be copied on its adjacent combobox at Row 2.

For example, if I select value on (1,3), same value will appear on (2,3). The same thing goes to Row 3 & 4, Row 5 & 6, and so on.

This is the code on my class module clsLineCopy:

Public WithEvents myCbo As msForms.ComboBox

Private Sub myCbo_Change()
    Dim i As Integer

    'MsgBox "Combo Box " & myCbo.Value & " has changed"
    If myCbo.Value <> "" Then
        myCbo.Copy
        myCbo.Paste
    End If
End Sub

This one is my code on my userform_initialize:

Dim myCommonCbo As New Collection
Dim cbo As clsLineCopy
For i = 1 To 70
    Set cbo = New clsLineCopy
    Set cbo.myCbo = Me.Controls("ComboBox" & i)
    myCommonCbo.Add Item:=cbo
Next i
Set cbo = Nothing

I know my code in the class module is wrong as I have no idea about it.

Thanks, Izz.

Answer 1

In my demo I named the Userform -> FormComboGrid

Here are the changes you need:

• Userform: Public CallBack method

• Userform: Class level boolean variable used to prevent cascading CallBacks

• myCommonCbo has to be elevated to a Class Level Variable. This keeps the references valid after the UserForm_Initialize finishes execution.

  • clsLineCopy should have an Init method used to pass a reference of the Userform instance and the Combobox that is being hooked.

FormComboGrid:Class

Option Explicit
Private myCommonCbo  As New Collection
Private ComboBoxEventEnabled As Boolean

Private Sub UserForm_Initialize()
    Dim i As Long
    Dim cbo As clsLineCopy
    For i = 1 To 70
        Set cbo = New clsLineCopy
        cbo.Init Me, Me.Controls("ComboBox" & i)
        myCommonCbo.Add Item:=cbo
       ' Me.Controls("ComboBox" & i).List = Array(1, 2, 3, 4, 5, 6, 7)
    Next i

    ComboBoxEventEnabled = True
End Sub

Public Sub ComboboxChange(cbo As MSForms.ComboBox)
    If Not ComboBoxEventEnabled Then Exit Sub
    ComboBoxEventEnabled = False

    Dim index As Long, r As Long, c As Long
    Dim myCbo As MSForms.ComboBox
    index = Replace(cbo.Name, "ComboBox", "")
    c = index Mod 10
    r = Int(index / 10) + 1
    If r = 7 Then Exit Sub

    index = ((r * 10) + c)
    Set myCbo = Me.Controls("ComboBox" & index)
    myCbo.Value = cbo.Value

    ComboBoxEventEnabled = True
End Sub

clsLineCopy:Class

Option Explicit

Private WithEvents myCbo As MSForms.ComboBox
Private mForm As FormComboGrid

Private Sub myCbo_Change()
    mForm.ComboboxChange myCbo
End Sub

Public Sub Init(Form As FormComboGrid, cbo As MSForms.ComboBox)
    Set mForm = Form
    Set myCbo = cbo
End Sub