Change event of Combobox in Userform not getting triggered - excel

Question

I have a userform and a Click button on it. On click of this button a combobox is dynamically created. I want to do something when a particular value is selected from this combobox but the change event is not getting triggered. What could be the reason.
Here is my code which is put in the UserForm1 module.
Private WithEvents ComboBox1 As MSForms.ComboBox
Private Sub ClickButton_Click()
'Create combo box
Dim ComboBox1 As MSForms.ComboBox
Set ComboBox1 = Me.Controls.Add("Forms.ComboBox.1")
With ComboBox1
.Left = 160
.Top = 50
.Width = 70
.Height = 20
.AddItem ("> than")
.AddItem ("< than")
.AddItem ("Max")
.AddItem ("Min")
.Enabled = True
.BackColor = RGB(255, 255, 255)
.ForeColor = RGB(0, 0, 0)
.SpecialEffect = fmSpecialEffectFlat
.Font.Size = 12
.Font.Bold = False
.Font.Name = "Arial"
.TabIndex = 2
End With
DoEvents
ComboBox1.SetFocus
End Sub
Private Sub ComboBox1_Change()
Dim inputNumber As Variant
If ComboBox1.Value = "> than" Then
inputNumber = InputBox("Enter a number:")
'Check if the input is valid number
If IsNumeric(inputNumber) Then
ComboBox1.Value = ComboBox2.Value & " " & inputNumber
Else
MsgBox "Invalid input"
End If
End If
End Sub

Answer 1

The method you need to use is described here: https://stackoverflow.com/a/8986622/9852011 , but for your particular case, here is what you need to do:
This is the code that should be in the module of your UserForm:
Private m_oCollectionOfEventHandlers As Collection
Private Sub UserForm_Initialize()
Set m_oCollectionOfEventHandlers = New Collection
End Sub
Private Sub CommandButton1_Click()
Dim ComboBox1 As MSForms.ComboBox
Set ComboBox1 = Me.Controls.Add("Forms.ComboBox.1")
With ComboBox1
.Left = 160
.Top = 50
.Width = 70
.Height = 20
.AddItem ("> than")
.AddItem ("< than")
.AddItem ("Max")
.AddItem ("Min")
.Enabled = True
.BackColor = RGB(255, 255, 255)
.ForeColor = RGB(0, 0, 0)
.SpecialEffect = fmSpecialEffectFlat
.Font.Size = 12
.Font.Bold = False
.Font.Name = "Arial"
.TabIndex = 2
End With
DoEvents
ComboBox1.SetFocus
Dim cb1EventHandler As comboboxeventhandler
Set cb1EventHandler = New comboboxeventhandler
Set cb1EventHandler.ComboBox = ComboBox1
m_oCollectionOfEventHandlers.Add cb1EventHandler
End Sub
Then, insert a new class module into your project, name it "ComboBoxEventHandler" and put this code into it:
Private WithEvents m_oComboBox As MSForms.ComboBox
Public Property Set ComboBox(ByVal oComboBox As MSForms.ComboBox)
Set m_oComboBox = oComboBox
End Property
Private Sub m_oComboBox_Change()
Dim inputNumber As Variant
With m_oComboBox
If .Value = "> than" Then
inputNumber = InputBox("Enter a number:")
'Check if the input is valid number
If IsNumeric(inputNumber) Then
.Value = .Parent.ComboBox2.Value & " " & inputNumber
Else
MsgBox "Invalid input"
End If
End If
End With
End Sub
I don't know what "ComboBox2" is but for the sake of this example, I just assumed it is a ComboBox which already exists in the UserForm somewhere.