Possible Values

Standard

The Visual is part of the layout, being sized by it's parent and contributing to it's size. Only standard Visual's are considered logical content of higher level controls like Navigation.

Placeholder

This has the same layout role as Standard exception it is not logical content for higher level controls.

Inert

The Visual inherits the layout of the parent but does not influece the parent layour. This is the default for items not in the Layout layer.

Independent

The Visual takes it's layout from somewhere other than it's parent. A Visual that uses LayoutMaster will get this role.