Q100357: SAMPLE: Xtenaccl.exe - Accelerators for File Manager Extensions

Article: Q100357
Product(s): Microsoft Windows Software Development Kit
Version(s): WINDOWS:3.1
Operating System(s): 
Keyword(s): kbfile kbsample kbFileManExt kbHook kbInput kbKeyAccel kbGrpDSUser kbOSWin310 kbGrpDSSh
Last Modified: 31-JUL-2001

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The information in this article applies to:

- Microsoft Windows Software Development Kit (SDK) 3.1 
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SUMMARY
=======

Xtenaccl.exe is a sample that installs a task-specific message hook
(WH_GETMESSAGE) and calls TranslateAccelerator() on every WM_KEY and WM_KEYDOWN
message. If an appropriate accelerator is found, TranslateAccelerator() passes a
WM_COMMAND to the main window. File Manager extensions cannot directly use
accelerators because extensions do not have their own message pump. File Manager
pulls messages on behalf of the extensions, and does not load and translate
extension's accelerators.

MORE INFORMATION
================

The following file is available for download from the Microsoft Download
Center:

  Xtenaccl.exe
  (http://download.microsoft.com/download/platformsdk/sample/6/W31/EN-US/Xtenaccl.exe)

For additional information about how to download Microsoft Support files, click
the article number below to view the article in the Microsoft Knowledge Base:

  Q119591 How to Obtain Microsoft Support Files from Online Services

Microsoft used the most current virus detection software available on the date of
posting to scan this file for viruses. Once posted, the file is housed on secure
servers that prevent any unauthorized changes to the file.

The main window of File Manager handles and processes the WM_COMMAND message
passed to it by TranslateAccelerator(). However, File Manager does not know how
to handle that message because wParam (containing menu IDs) is defined by the
extension. To interpret the correct value, File Manager dynamically changes an
extension's menu IDs to suit its own needs. Therefore, XTENACCL traps the
WM_COMMAND message passed by TranslateAccelerator() and routes it to a child
window of its own. The child window in turn processes the menu command.

To intercept the WM_COMMAND message, XTENACCL is using a second message hook that
is of type WH_CALLWNDPROC. Because TranslateAccelerator() sends a WM_COMMAND
instead of posting it, this second hook was needed.

Additional query words: 0 file manager extension

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Keywords          : kbfile kbsample kbFileManExt kbHook kbInput kbKeyAccel kbGrpDSUser kbOSWin310 kbGrpDSShell kb16bitonly kbAcceleratorKey 
Technology        : kbAudDeveloper kbWin3xSearch kbSDKSearch kbWinSDKSearch kbWinSDK310
Version           : WINDOWS:3.1

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