The ShowWindow function sets the specified window's show state.
HWND hWnd, // handle to window
int nCmdShow // show state of window
Handle to the window.
Specifies how the window is to be shown. This parameter is ignored the first time an application calls ShowWindow, if the program that launched the application provides aSTARTUPINFO structure. Otherwise, the first time ShowWindow is called, the value should be the value obtained by the WinMain function in its nCmdShow parameter. In subsequent calls, this parameter can be one of the following values: Value Meaning
SW_FORCEMINIMIZE Windows NT 5.0 and later: Minimizes a window, even if the thread that owns the window is hung. This flag should only be used when minimizing windows from a different thread.
SW_HIDE Hides the window and activates another window.
SW_MAXIMIZE Maximizes the specified window.
SW_MINIMIZE Minimizes the specified window and activates the next top-level window in the Z order.
SW_RESTORE Activates and displays the window. If the window is minimized or maximized, the system restores it to its original size and position. An application should specify this flag when restoring a minimized window.
SW_SHOW Activates the window and displays it in its current size and position.
SW_SHOWDEFAULT Sets the show state based on the SW_ flag specified in theSTARTUPINFO structure passed to theCreateProcess function by the program that started the application.
SW_SHOWMAXIMIZED Activates the window and displays it as a maximized window.
SW_SHOWMINIMIZED Activates the window and displays it as a minimized window.
SW_SHOWMINNOACTIVE Displays the window as a minimized window. The active window remains active.
SW_SHOWNA Displays the window in its current state. The active window remains active.
SW_SHOWNOACTIVATE Displays a window in its most recent size and position. The active window remains active.
SW_SHOWNORMAL Activates and displays a window. If the window is minimized or maximized, the system restores it to its original size and position. An application should specify this flag when displaying the window for the first time.
If the window was previously visible, the return value is nonzero.
If the window was previously hidden, the return value is zero.
The first time an application calls ShowWindow, it should use the WinMain function's nCmdShow parameter as its nCmdShow parameter. Subsequent calls to ShowWindow must use one of the values in the given list, instead of the one specified by the WinMain function's nCmdShow parameter.
As noted in the discussion of the nCmdShow parameter, the nCmdShow value is ignored in the first call to ShowWindow if the program that launched the application specifies startup information in theSTARTUPINFO structure. In this case, ShowWindow uses the information specified in the STARTUPINFO structure to show the window. On subsequent calls, the application must call ShowWindow with nCmdShow set to SW_SHOWDEFAULT to use the startup information provided by the program that launched the application. This behavior is designed for the following situations:
Applications create their main window by calling CreateWindow with the WS_VISIBLE flag set.
Applications create their main window by calling CreateWindow with the WS_VISIBLE flag cleared, and later call ShowWindow with the SW_SHOW flag set to make it visible.
Windows CE: The nCmdShow parameter does not support the following values:
Windows NT: Requires version 3.1 or later.
Windows: Requires Windows 95 or later.
Windows CE: Requires version 1.0 or later.
Header: Declared in winuser.h.
Import Library: Use user32.lib.
Windows Overview, Window Functions,CreateProcess, CreateWindow, ShowOwnedPopups,STARTUPINFO, WinMain