VirtualizedItem Control Pattern

Describes guidelines and conventions for implementing IVirtualizedItemProvider, including information about properties and methods. The VirtualizedItem control pattern is used to support virtualized items, which are items that are represented by placeholder automation elements in the Microsoft UI Automation tree.

Virtualized items can include items retrieved from a control that supports the ItemContainer control pattern, or a virtualized embedded object retrieved from a control that supports the Text control pattern. The placeholder for a virtualized item might not have loaded data for all UI Automation properties, and may return UIA_E_ELEMENTNOTAVAILABLE in response to queries for properties that are not available. The VirtualizedItem control pattern provides a method for realizing a virtual item so that full information is made available for the item, and a full automation element can be created for the item in the UI Automation tree.

This topic contains the following sections.

Implementation Guidelines and Conventions

When implementing the VirtualizedItem control pattern, note the following guidelines and conventions:

Required Members for IVirtualizedItemProvider

The following properties and methods are required for implementing the IVirtualizedItemProvider interface.

Required members Member type Notes
Realize Method None


This control pattern has no associated events.

Implementing the UI Automation ItemContainer Control Pattern

UI Automation Control Patterns Overview

UI Automation Tree Overview

Working with Virtualized Items