Describes a VisualElement derived class for the parsing of UXML files and the generation of UXML schema definition.
UxmlTraits describes the UXML attributes and children elements of a class deriving from VisualElement. It is used by UxmlFactory to map UXML attributes to the C# class properties when reading UXML documents. It is also used to generate UXML schema definitions.
| canHaveAnyAttribute | Must return true if the UXML element attributes are not restricted to the values enumerated by uxmlAttributesDescription. |
| uxmlAttributesDescription | Describes the UXML attributes expected by the element. The attributes enumerated here will appear in the UXML schema. |
| uxmlChildElementsDescription | Describes the types of element that can appear as children of this element in a UXML file. |
| Init | Initialize a VisualElement instance with values from the UXML element attributes. |