Opisy znajdziejsz w Windows SDK tam gdzie jest opisany ShellHook, służący do robienia paska zadań.
ShellProc Function
The ShellProc hook procedure is an application-defined or library-defined callback function used with the SetWindowsHookEx function. The function receives notifications of Shell events from the system.
The HOOKPROC type defines a pointer to this callback function. ShellProc is a placeholder for the application-defined or library-defined function name.
Syntax
LRESULT CALLBACK ShellProc( int nCode,
WPARAM wParam,
LPARAM lParam
);
Parameters
nCode
[in] Specifies the hook code. If nCode is less than zero, the hook procedure must pass the message to the CallNextHookEx function without further processing and should return the value returned by CallNextHookEx. This parameter can be one of the following values.
HSHELL_ACCESSIBILITYSTATE
Windows 2000/XP: The accessibility state has changed.
HSHELL_ACTIVATESHELLWINDOW
The shell should activate its main window.
HSHELL_APPCOMMAND
Windows 2000/XP: The user completed an input event (for example, pressed an application command button on the mouse or an application command key on the keyboard), and the application did not handle the WM_APPCOMMAND message generated by that input.
If the Shell procedure handles the WM_COMMAND message, it should not call CallNextHookEx. See the Return Value section for more information.
HSHELL_GETMINRECT
A window is being minimized or maximized. The system needs the coordinates of the minimized rectangle for the window.
HSHELL_LANGUAGE
Keyboard language was changed or a new keyboard layout was loaded.
HSHELL_REDRAW
The title of a window in the task bar has been redrawn.
HSHELL_TASKMAN
The user has selected the task list. A shell application that provides a task list should return TRUE to prevent Microsoft® Windows® from starting its task list.
HSHELL_WINDOWACTIVATED
The activation has changed to a different top-level, unowned window.
HSHELL_WINDOWCREATED
A top-level, unowned window has been created. The window exists when the system calls this hook.
HSHELL_WINDOWDESTROYED
A top-level, unowned window is about to be destroyed. The window still exists when the system calls this hook.
HSHELL_WINDOWREPLACED
Windows XP: A top-level window is being replaced. The window exists when the system calls this hook.
wParam
[in] The value depends on the value of the nCode parameter, as shown in the following table. nCode wParam
HSHELL_ACCESSIBILITYSTATE Windows 2000/XP: Indicates which accessibility feature has changed state. This value is one of the following: ACCESS_FILTERKEYS, ACCESS_MOUSEKEYS, or ACCESS_STICKYKEYS.
HSHELL_APPCOMMAND Windows 2000/XP: Where the WM_APPCOMMAND message was originally sent; for example, the handle to a window. For more information, see cmd parameter in WM_APPCOMMAND.
HSHELL_GETMINRECT Handle to the minimized or maximized window.
HSHELL_LANGUAGE Handle to the window.
HSHELL_REDRAW Handle to the redrawn window.
HSHELL_WINDOWACTIVATED Handle to the activated window.
HSHELL_WINDOWCREATED Handle to the created window.
HSHELL_WINDOWDESTROYED Handle to the destroyed window.
HSHELL_WINDOWREPLACED Windows XP: Handle to the window being replaced.
lParam
[in] The value depends on the value of the nCode parameter, as shown in the following table. nCode lParam
HSHELL_APPCOMMAND Windows 2000/XP:GET_APPCOMMAND_LPARAM(lParam) is the application command corresponding to the input event.
GET_DEVICE_LPARAM(lParam) indicates what generated the input event; for example, the mouse or keyboard. For more information, see the uDevice parameter description under WM_APPCOMMAND.
GET_FLAGS_LPARAM(lParam) depends on the value of cmd in WM_APPCOMMAND. For example, it might indicate which virtual keys were held down when the WM_APPCOMMAND message was originally sent. For more information, see the dwCmdFlags description parameter under WM_APPCOMMAND.
HSHELL_GETMINRECT Pointer to a RECT structure.
HSHELL_LANGUAGE Handle to a keyboard layout.
HSHELL_REDRAW The value is TRUE if the window is flashing, or FALSE otherwise.
HSHELL_WINDOWACTIVATED The value is TRUE if the window is in full-screen mode, or FALSE otherwise.
HSHELL_WINDOWREPLACED Windows XP: Handle to the new window.
Return Value
The return value should be zero unless the value of nCode is HSHELL_APPCOMMAND and the shell procedure handles the WM_COMMAND message. In this case, the return should be nonzero.
Remarks
Install this hook procedure by specifying the WH_SHELL hook type and a pointer to the hook procedure in a call to the SetWindowsHookEx function.
Function Information
Header Declared in Winuser.h, include Windows.h
Import library None
Minimum operating systems Windows 95, Windows NT 3.1