Поделиться через

Working with the Scope Pane: Implementation Details

  • Статья

The following procedure applies to primary snap-ins that insert their own items into the scope pane. For more information about how extension snap-ins can add items to the scope pane of a primary snap-in, see Extending a Primary Snap-in's Namespace.

To insert items in the scope pane

  1. Determine the tree structure of the snap-in's scope pane; that is, how many child items the snap-in's root node (the static node) inserts, and whether these items have child items. Associate a snap-in object with each item in the scope pane, and determine a method for instantiating these objects.

    Also, determine the node type GUID for each item in the scope pane. You can use the uuidgen.exe tool for generating GUIDs.

    For more information about nodes, see Snap-in Namespace.

  2. Handle the MMCN_EXPAND notification message, which MMC sends to the snap-in's IComponentData implementation when a scope item is selected for the first time in the scope pane. In response to the notification, the snap-in should do the following:

    • If the selected item has child items, the snap-in must fill a SCOPEDATAITEM structure for each child item and then insert the item in the scope pane by calling the IConsoleNamespace2::InsertItem method with a pointer to the address of the SCOPEDATAITEM structure. When InsertItem returns (with S_OK), the ID member of the SCOPEDATAITEM structure contains the HSCOPEITEM of the newly inserted item. Snap-ins should store the HSCOPEITEM of each inserted item and use it to later manipulate the item using the methods of the IConsole2 and IConsoleNameSpace2 interfaces.

      Be aware that when filling a SCOPEDATAITEM structure for a child item, the snap-in can also specify whether that child item has child items of its own. If it does not have any child items, the snap-in should set the cChildren member of the structure to 0. This instructs MMC to hide the plus (+) sign when inserting the child item. If conditions change and the inserted child item has child items at a later time, the snap-in can modify the cChildren member by using IConsoleNameSpace2::SetItem.

    • If the selected item does not have any child items, the snap-in must return S_FALSE.

  3. Implement the IComponentData::GetDisplayInfo method. When inserting a scope item or a result item into MMC, the display name must be set to MMC_CALLBACK. After the snap-in returns from the MMCN_EXPAND notification handler, MMC calls GetDisplayInfo once for each inserted item in the scope pane (for which SCOPEDATAITEM.displayname = MMC_CALLBACK) to request the item's display name.

  4. If necessary, handle the MMCN_EXPANDSYNC notification.

Working with the Scope Pane: Interfaces

Working with the Scope Pane: Additional Topics