Is it possible to access a parent property from a child that is in a collection?

Question

I've researched as much as I can and never found a definitive answer on this for VBA. This older StackOverflow post has almost everything, but not quite. VBA Classes - How to have a class hold additional classes Bottom line - I have a class CClock, which is parent to a Collection of CContacts, which is parent to a CContact. Is there any way to get at a property of the CClock class from a CContact. So something like `Debug.Print , clsContact.Parent.Parent.Lawyer` in the code below? I've tried setting the parents as I thought they should be but get the below error almost immediately at `Set clsClock = New CClock`. When I follow the code it goes to class terminate event in the Contacts collection, which I can't figure out. (Although that is probably why the error below comes up.) `91 - Object Variable or With Variable not set` The various classes and a quick test rig are below (all based on Dick Kusleika's post in the link.) Thanks. (Edit- added the test routine, whooopsy) ``` Sub test()…

Accepted Answer

If you figure out how to access the kernel memory to do this, let me know. Take a look at the source code of vbWatchDog for some hints. I have been studying it to try to gain access to the call stack. I haven't figured it out yet.

I'll show you how to fake it though. I'm going to simplify this a bit. You'll need to apply the principle to your own code. The trick is kind of ugly. It requires that we call an `Initialize` routine each time we create a new child object

The Parent Class:

```
'Class Parent
Option Explicit

Private mName as String
Public Property Get Name() as String
    Name = mName()
End Property

Public Property Let Name(value As String)
    mName = value
End Property
```

The Child class

```
'Class Child
Option Explicit

Private mParent as Parent

Public Property Get Parent() as Parent
    Set Parent = mParent
End Property

Public Property Let Name(Obj as Parent)
    Set mParent = Obj
End Property

Public Sub Initialize(Obj as Parent)
    Set Me.Parent = Obj
End Sub
```

Creating a Child object:

```
Sub CreateChild()
    Dim parentObject As New Parent
    ' create child object with parent property
    Dim childObject As New Child
    childObject.Initialize(parentObject)
End Sub
```

Is it possible to access a parent property from a child that is in a collection?

Solution

Problem

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