| Posted by: |  | Vincentt | 
| Data created: | 8 January 2015 | |
| Hello, I’m yet again stuck, I apologize for all the questions I’ve been posting recently, but all of the answers have been very helpful, so I’m trying it again :) I want to register some callbacks to update my UI accordingly. One of them is a global one I was able to register with the help of the documentation: http://www.ephere.com/autodesk/max/docs/902.html. (SystemNotificationCode.SelNodesPostDelete). Problem 1: Now I would like to also have a callback for when the stack of my object(s) is getting collapsed. I found: 
 in ‘IBaseObject’ however I don’t know how to actually register to it? I thought about inheriting IBaseObject, this didn’t really work because then I’d have to implement all the methods from IBaseObject, I tried to inherit from BaseObject but even then I don’t know what to do with my new class… 
 Problem 2: I want to register an INodeEvenCallback. I got this so far: 
 
 
 This doesn’t work though, am I registering it correctly, with CreateUnmanagedWrapper? I’ve also tried .Create() and .InitializeLifetimeService() without luck. 
 Thank you in advance! 
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| 9 January 2015 
											#5718 | |
| Hi Vin, NotifyPostCollapse should be a method you override in your plugin (Texture/Modifier/GeomObject/etc.). It will be called by Max whenever it collapses your object. You don't "subscribe" to it with a callback, it is something you override. This is how you register INodeEventCallback: 
 Marsel Khadiyev (Software Developer, EPHERE Inc.) | |
| 9 January 2015 
											#5719 | |
| Hey Marsel, Thanks for the reply! I have 1 question about the NotifyPostCollapse method. I have this as my base plugin class: 
 So I don't think I have a "real" plugin. I have a WinForm where I draw all my information on and I use GlobalInterface to get everything. Is it possible then to override NotifyPostCollapse? It sounds like this is not a "global" callback but per Node one. 
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