FMExtensionProc
The FMExtensionProc
function is an application-defined callback function that processes menu
commands and messages sent to a File Manager extension dynamic-link library
(DLL).
LONG WINAPI FMExtensionProc(
|
HWND hwnd, |
// handle to
extension window |
|
WORD wEvent, |
// menu-item
identifier, or message |
|
LONG lParam |
// additional
message information |
|
); |
|
Parameters
hwnd
Identifies
the File Manager window. An extension DLL should use this handle to specify the
owner for any dialog box or message box that the DLL may display and to send
request messages to File Manager.
wEvent
Specifies the
message. This parameter can be one of the following values:
|
Value |
Meaning |
|
1-99 |
The user
selected the menu item identified by this number. |
|
FMEVENT_INITMENU |
User
selected the extension s menu. |
|
FMEVENT_LOAD |
File
Manager is loading the extension DLL. |
|
FMEVENT_SELCHANGE |
Selection
changed in File Manager s directory window or in Search Results window. |
|
FMEVENT_UNLOAD |
File
Manager is unloading the extension DLL. |
|
FMEVENT_USER_REFRESH |
User chose
the Refresh command from the Window menu. |
lParam
Specifies 32
bits of additional message-specific information.
Return Values
The callback
function should return the result of the message processing. The actual return
value depends on the message processed.
Remarks
Whenever File
Manager calls the FMExtensionProc function, it waits to refresh its
directory windows (for changes in the file system) until after the function
returns. This allows the extension to perform large numbers of file operations
without excessive repainting by File Manager. It is not necessary for the
extension to send the FM_REFRESH_WINDOWS message to notify File Manager to
repaint its windows.