VBA Excel用户窗体EventHandler，用于动态生成的控件无法按预期工作

Question

I'm working in Excel 2013, designing a Userform with controls created at run-time. I'm having trouble making a function that will fire on the change event of the dynamically created controls.

The controls are contained in a separate class module that creates them and manages them. I want to add a function that fires on the change event of a combo-box, so I have it declared WithEvents:

Private WithEvents myComboBox As MSForms.ComboBox
... other controls and variable declarations...

I have a function that is passed the frame that I want the controls to be in so that I can create all the components from within the class.

Sub initialize(myID As String, myFrame As MSForms.Frame, Left As Double, Top As Double)
    ...
    Set myComboBox = myFrame.Controls.Add("Forms.ComboBox.1", myID & "_comboBox")
    ...
End Sub

This all works, and the ComboBox is created and properties changed though myComboBox successfully change how the ComboBox appears.

Because myComboBox is declared WithEvents , I can find myComboBox_Change as an option in the drop-down menus and put it in the module:

Private Sub myComboBox_Change()
    MsgBox ("Change Event Fired")
End Sub

But this function will not run, and I can't figure out why. A messagebox will not appear when a change is made, and breakpoint put in this function will not stop any code from running. What am I doing wrong?

Answer 1

With the help of some probing questions from cyboashu, I figured out what was wrong. The class containing myComboBox was not held by a variable declared for the scope of the entire userform. After the function creating it completed, the components were still in myFrame , but the functions to be fired on events were forgotten