LPFNVIEWCALLBACK callback function (shlobj_core.h)

Article
10/13/2021

[This interface is supported through Windows XP Service Pack 2 (SP2) and Windows Server 2003. It might be unsupported in subsequent versions of Windows.]

Defines the prototype for the callback function used by the system folder view object. This function essentially duplicates the functionality of IShellFolderViewCB.

Syntax

LPFNVIEWCALLBACK Lpfnviewcallback;

HRESULT Lpfnviewcallback(
  [in] IShellView *psvOuter,
  [in] IShellFolder *psf,
  [in] HWND hwndMain,
       UINT uMsg,
       WPARAM wParam,
       LPARAM lParam
)
{...}

Parameters

[in] psvOuter

Type: IShellView*

A pointer to the owning instance of IShellView, if applicable. This parameter can be NULL.

[in] psf

Type: IShellFolder*

A pointer to the instance of IShellFolder the message applies to.

[in] hwndMain

Type: HWND

The handle of the window that contains the view that receives the message.

uMsg

Type: UINT

One of the following notifications.

SFVM_ADDPROPERTYPAGES

Allows the callback object to provide a page to add to the Properties property sheet of the selected object.

SFVM_BACKGROUNDENUM

Allows the callback object to request that enumeration be done on a background thread.

SFVM_BACKGROUNDENUMDONE

Notifies the callback object that background enumeration is complete.

SFVM_COLUMNCLICK

Notifies the callback object that the user has clicked a column header to sort the list of objects in the folder view.

SFVM_DEFITEMCOUNT

Allows the callback object to specify the number of items in the folder view.

SFVM_DEFVIEWMODE

Allows the callback object to specify the view mode.

SFVM_DIDDRAGDROP

Notifies the callback function that a drag-and-drop operation has begun.

SFVM_FSNOTIFY

Notifies the callback object that an event has taken place that affects one of its items.

SFVM_GETANIMATION

Allows the callback object to specify that an animation be displayed while items are enumerated on a background thread.

SFVM_GETBUTTONINFO

Allows the callback object to add buttons to the toolbar.

SFVM_GETBUTTONS

Allows the callback object to specify the buttons to be added to the toolbar.

SFVM_GETDETAILSOF

Allows the callback object to provide the details for an item in a Shell folder. Use only if a call to IShellFolder2::GetDetailsOf fails and there is no IShellDetails::GetDetailsOf method available to call.

SFVM_GETHELPTEXT

Allows the callback object to specify a help text string for menu items or toolbar buttons.

SFVM_GETHELPTOPIC

Allows the callback object to specify a Help file and topic.

SFVM_GETNOTIFY

Specifies which events will generate an SFVM_FSNOTIFY message for a given item.

SFVM_GETPANE

Allows the callback object to provide the status bar pane in which to display the Internet zone information.

SFVM_GETSORTDEFAULTS

Allows the callback object to specify default sorting parameters.

SFVM_GETTOOLTIPTEXT

Allows the callback object to specify a tooltip text string for menu items or toolbar buttons.

SFVM_GETZONE

Allows the callback object to provide Internet zone information.

SFVM_INITMENUPOPUP

Allows the callback object to modify an item's context menu.

SFVM_INVOKECOMMAND

Notifies the callback object that one of its toolbar or menu commands has been invoked.

SFVM_MERGEMENU

Allows the callback object to merge menu items into the Windows Explorer menus.

SFVM_QUERYFSNOTIFY

Allows the callback object to register a folder so that changes to that folder's view will generate notifications.

SFVM_SETISFV

Notifies the callback object of the container site. This is used only when IObjectWithSite::SetSite is not supported and SHCreateShellFolderViewEx is used.

SFVM_SIZE

Notifies the callback object that the folder view has been resized.

SFVM_THISIDLIST

Allows the callback object to specify the view's PIDL. This is used only when IPersistIDList::SetIDList and IPersistFolder2::GetCurFolder have failed.

SFVM_UNMERGEMENU

Notifies the callback object that a menu is being removed.

SFVM_UPDATESTATUSBAR

Allows the callback object to request that the status bar be updated.

SFVM_WINDOWCREATED

Notifies the callback object that the folder view window is being created.

wParam

Type: WPARAM

Additional information dependent on the value in uMsg. See the individual notification pages for specific requirements.

lParam

Type: LPARAM