You could use OpenUserObjectWithParm and pass the parent window. Then in the object constructor event, save a reference to it in and instance variable like this:

iw_parent = Message.PowerObjectParm

Thanks Smith,

Your suggestion is helpful.

But my question is, if the user object open as a control in window (using OpenUserObject), why I am not getting Parent object?

I don't know. I just tried with a button object and it worked as expected. This isn't PFC, just a simple one window app.

Code in the button object:

Window lw_parent

lw_parent = this.GetParent()

If IsNull(lw_parent) Then
    MessageBox("GetParent", "Null")
Else
    MessageBox("GetParent", lw_parent.title)
End If

Code in the window open event:

OpenUserObject(u_cbparent, 10, 10)

So you added a GetParent() to u_dw and it returns null?

u_dw is a "standard visual" object inherited from datawindow, so you should place it on your window or userobject at design time using the menu option

Insert > Control > User Object...

Normally, you would not open u_dw using OpenUserObject(), which is usually used for "custom visual" objects (such as u_base).