| LRESULT CALLBACK ShellProc(code, wParam, lParam) | |||||
| int code; | /* hook code | */ | |||
| WPARAM wParam; | /* current-task flag | */ | |||
| LPARAM lParam; | /* undefined | */ | |||
The ShellProc function is an application- or library-defined callback function that a shell application can use to receive useful notifications from the system.
code
Specifies a shell-notification code. This parameter can be one of the following values:
| Value | Meaning |
| HSHELL_ACTIVATESHELLWINDOW | ||
| The shell application should activate its main window. | ||
| HSHELL_WINDOWCREATED | ||
| A top-level, unowned window was created. The window exists when the system calls a ShellProc function. | ||
| HSHELL_WINDOWDESTROYED | ||
| A top-level, unowned window is about to be destroyed. The window still exists when the system calls a ShellProc function. | ||
wParam
Specifies additional information the shell application may need. The interpretation of this parameter depends on the value of the code parameter, as follows:
| code | wParam |
| HSHELL_ACTIVATESHELLWINDOW | ||
| Not used. | ||
| HSHELL_WINDOWCREATED | ||
| Specifies the handle of the window being created. | ||
| HSHELL_WINDOWDESTROYED | ||
| Specifies the handle of the window being destroyed. | ||
lParam
Reserved; not used.
The return value should be zero.
An application must install this callback function by specifying the WH_SHELL filter type and the procedure-instance address of the callback function in a call to the SetWindowsHookEx function.
ShellProc is a placeholder for the application- or library-defined function name. The actual name must be exported by including it in the EXPORTS statement in a module-definition file.
CallNextHookEx, SendMessage, SetWindowsHookEx