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                        Using Keyboard Accelerators
 
An application can automatically load an accelerator table
resource-definition file when creating a standard frame window, or it can
load the resource independently and associate it with a window or with the
entire system.
 
An application can set and query the accelerator tables for a specific
window or for the entire system. For example, an application could query the
system accelerator table, copy it, modify the copied accelerator-table data
structures, and then use the modified copy to set the system accelerator
table. An application that does this should maintain the original
accelerator table and restore it when the application terminates. An
application can also modify its window's accelerator table at run time to
respond more appropriately to the current environment.
 
Including an Accelerator Table in a Frame Window
 
An application can add an accelerator table to a frame window either by
using the WinSetAccelTable function or by defining an accelerator-table
resource and creating a frame window with the FCF_ACCELTABLE frame style.
The second method is shown in the following code fragment:
 
ULONG lControlStyle = FCF_MENU | FCF_SIZEBORDER
                      | FCF_TITLEBAR | FCF_ACCELTABLE;
 
hwndFrame = WinCreateStdWindow (HWND_DESKTOP,
    WS_VISIBLE,
    &lControlStyle,
    szClassName,
    szTitle,
    0L, NULL,
    ID_MENU_RESOURCE,
    &hwndClient);
 
Note that if you set the lControlStyle parameter to FCF_STANDARD you must
define an accelerator-table resource, because FCF_STANDARD includes the
FCF_ACCELTABLE flag.
 
If the window being created also has a menu, the menu resource and the
accelerator resource must have the same resource identifier; this is because
the WinCreateStdWindow function has only one input parameter to specify the
resource ID of menus, accelerator tables, and icons. If an application
creates an accelerator table resource-definition file and then opens a
standard frame window, as shown in the preceding example, the accelerator
table is automatically installed in the window's input queue and keyboard
events are translated during the normal processing of events. The
application simply responds to WM_COMMAND, WM_SYSCOMMAND, and WM_HELP
messages; it does not matter whether they come from a menu or from an
accelerator.
 
An application can also add an accelerator table to a window by calling the
WinSetAccelTable function with an accelerator-table handle and a
frame-window handle. The application can call either the WinLoadAccelTable
function to retrieve an accelerator table from a resource file or the
WinCreateAccelTable function to create an accelerator table from an
accelerator-table data structure in memory.
 
Modifying an Accelerator Table
 
An application can modify an accelerator table, either for its own windows
or for the system, by retrieving the handle of the accelerator table, using
the handle to copy the accelerator-table data to an application-supplied
buffer, changing the data in the buffer, and then using the data in the
buffer to create a new accelerator table. The application can then use the
new accelerator-table handle to set the accelerator table, either for a
window or for the system. This process is outlined in the following list:
 
1  Call the WinQueryAccelTable function to retrieve an accelerator-table
   handle.
 
2  Call the WinCopyAccelTable function with a null buffer handle to
   determine how many bytes are in the table.
 
3  Allocate sufficient memory for the accelerator-table data.
 
4  Call the WinCopyAccelTable function with a pointer to the allocated
   memory.
 
5  Modify the data in the buffer (assuming it has the form of an ACCELTABLE
   data structure).
 
6  Call the WinCreateAccelTable function, passing a pointer to the buffer
   with the modified accelerator-table data.
 
7  Call the WinSetAccelTable function with the handle returned by the
   WinCreateAccelTable function.
 
 
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