WPF Event to capture newly added controls?

We use the ContentControl and other containe开发者_运维问答rs stuff in WPF. I need the notification with the new child control is added to the container. What is the best way to get the newly created control within parent?

The ContentControl only contains a single child which is attached via the ContentControl.Content property. You can hook the ContentControl.OnContentChanged to discover when the value of this property is updated.

The cleanest way is to derive from those control and override the methods that report the changes you are interested in. For example derive from ContentControl and implement OnContentChanged. This approach may not appeal to you.

If you want to detect changes in the child or children of controls without deriving from them, you can observe that such changes will affect the layout and so you can hook the LayoutUpdated event. The problem with this approach is that you need to keep track of the children that were previously added yourself by inspecting Child or Children looking for changes. You also have to be careful not to hang onto references to former children lest you create a memory leak. But it can be done.