ModifyMenuA function

Changes an existing menu item. This function is used to specify the content, appearance, and behavior of the menu item.

Note  The ModifyMenu function has been superseded by the SetMenuItemInfo function. You can still use ModifyMenu, however, if you do not need any of the extended features of SetMenuItemInfo.
 

Syntax

BOOL ModifyMenuA(
  HMENU    hMnu,
  UINT     uPosition,
  UINT     uFlags,
  UINT_PTR uIDNewItem,
  LPCSTR   lpNewItem
);

Parameters

hMnu

Type: HMENU

A handle to the menu to be changed.

uPosition

Type: UINT

The menu item to be changed, as determined by the uFlags parameter.

uFlags

Type: UINT

Controls the interpretation of the uPosition parameter and the content, appearance, and behavior of the menu item. This parameter must include one of the following required values.

Value Meaning
MF_BYCOMMAND
0x00000000L
Indicates that the uPosition parameter gives the identifier of the menu item. The MF_BYCOMMAND flag is the default if neither the MF_BYCOMMAND nor MF_BYPOSITION flag is specified.
MF_BYPOSITION
0x00000400L
Indicates that the uPosition parameter gives the zero-based relative position of the menu item.
 

The parameter must also include at least one of the following values.

Value Meaning
MF_BITMAP
0x00000004L
Uses a bitmap as the menu item. The lpNewItem parameter contains a handle to the bitmap.
MF_CHECKED
0x00000008L
Places a check mark next to the item. If your application provides check-mark bitmaps (see the SetMenuItemBitmaps function), this flag displays a selected bitmap next to the menu item.
MF_DISABLED
0x00000002L
Disables the menu item so that it cannot be selected, but this flag does not gray it.
MF_ENABLED
0x00000000L
Enables the menu item so that it can be selected and restores it from its grayed state.
MF_GRAYED
0x00000001L
Disables the menu item and grays it so that it cannot be selected.
MF_MENUBARBREAK
0x00000020L
Functions the same as the MF_MENUBREAK flag for a menu bar. For a drop-down menu, submenu, or shortcut menu, the new column is separated from the old column by a vertical line.
MF_MENUBREAK
0x00000040L
Places the item on a new line (for menu bars) or in a new column (for a drop-down menu, submenu, or shortcut menu) without separating columns.
MF_OWNERDRAW
0x00000100L
Specifies that the item is an owner-drawn item. Before the menu is displayed for the first time, the window that owns the menu receives a WM_MEASUREITEM message to retrieve the width and height of the menu item. The WM_DRAWITEM message is then sent to the window procedure of the owner window whenever the appearance of the menu item must be updated.
MF_POPUP
0x00000010L
Specifies that the menu item opens a drop-down menu or submenu. The uIDNewItem parameter specifies a handle to the drop-down menu or submenu. This flag is used to add a menu name to a menu bar or a menu item that opens a submenu to a drop-down menu, submenu, or shortcut menu.
MF_SEPARATOR
0x00000800L
Draws a horizontal dividing line. This flag is used only in a drop-down menu, submenu, or shortcut menu. The line cannot be grayed, disabled, or highlighted. The lpNewItem and uIDNewItem parameters are ignored.
MF_STRING
0x00000000L
Specifies that the menu item is a text string; the lpNewItem parameter is a pointer to the string.
MF_UNCHECKED
0x00000000L
Does not place a check mark next to the item (the default). If your application supplies check-mark bitmaps (see the SetMenuItemBitmaps function), this flag displays a clear bitmap next to the menu item.

uIDNewItem

Type: UINT_PTR

The identifier of the modified menu item or, if the uFlags parameter has the MF_POPUP flag set, a handle to the drop-down menu or submenu.

lpNewItem

Type: LPCTSTR

The contents of the changed menu item. The interpretation of this parameter depends on whether the uFlags parameter includes the MF_BITMAP, MF_OWNERDRAW, or MF_STRING flag.

Value Meaning
MF_BITMAP
0x00000004L
A bitmap handle.
MF_OWNERDRAW
0x00000100L
A value supplied by an application that is used to maintain additional data related to the menu item. The value is in the itemData member of the structure pointed to by the lParam parameter of the WM_MEASUREITEM or WM_DRAWITEM messages sent when the menu item is created or its appearance is updated.
MF_STRING
0x00000000L
A pointer to a null-terminated string (the default).

Return Value

Type: BOOL

If the function succeeds, the return value is nonzero.

If the function fails, the return value is zero. To get extended error information, call GetLastError.

Remarks

If ModifyMenu replaces a menu item that opens a drop-down menu or submenu, the function destroys the old drop-down menu or submenu and frees the memory used by it.

In order for keyboard accelerators to work with bitmap or owner-drawn menu items, the owner of the menu must process the WM_MENUCHAR message. See Owner-Drawn Menus and the WM_MENUCHAR Message for more information.

The application must call the DrawMenuBar function whenever a menu changes, whether the menu is in a displayed window. To change the attributes of existing menu items, it is much faster to use the CheckMenuItem and EnableMenuItem functions.

The following groups of flags cannot be used together:

  • MF_BYCOMMAND and MF_BYPOSITION
  • MF_DISABLED, MF_ENABLED, and MF_GRAYED
  • MF_BITMAP, MF_STRING, MF_OWNERDRAW, and MF_SEPARATOR
  • MF_MENUBARBREAK and MF_MENUBREAK
  • MF_CHECKED and MF_UNCHECKED

Examples

For an example, see Setting Fonts for Menu-Item Text Strings.

Requirements

   
Minimum supported client Windows 2000 Professional [desktop apps only]
Minimum supported server Windows 2000 Server [desktop apps only]
Target Platform Windows
Header winuser.h (include Windows.h)
Library User32.lib
DLL User32.dll

See Also

AppendMenu

CheckMenuItem

Conceptual

DrawMenuBar

EnableMenuItem

Menus

Reference

SetMenuItemBitmaps

SetMenuItemInfo