FrameworkElement.AddLogicalChild Method (Object)
Adds the provided object to the logical tree of this element.
Assembly: PresentationFramework (in PresentationFramework.dll)
Use this method for the implementation of collections on objects that represent logical child elements of an element. Collection maintenance for child element collections might be done in property getters or setters, class handling of Changed events, constructors, or within the collection types themselves.
For control authors, manipulating the logical tree at this level is not the recommended practice, unless none of the content models for available base control classes are appropriate for your control scenario. Consider subclassing at the level of ContentControl, ItemsControl, and HeaderedItemsControl. These classes provide a content model with particular enforcement of logical tree child elements through dedicated APIs, as well as support for other features typically desirable in a WPF control such as styling through templates. For more information on how to use LogicalChildren and , see Trees in WPF.
may throw an exception if called at a time when the logical tree is being iterated by another process.
The following example implements a Child property on a custom FrameworkElement that does its own visual layer implementation. The property setter is designed so that if the value changes, the old value is removed from the logical tree, as well as a class-specific visual collection. The property value is cached, and then the new value is added to both the logical tree and the custom visual collection.
Available since 3.0