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Using Menus

This section describes the following tasks:

Using a Menu-Template Resource

You typically include a menu in an application by creating a menu-template resource and then loading the menu at run time. This section describes the format of a menu template, and explains how to load a menu-template resource and use it in your application. For information about creating a menu-template resource, see the documentation included with your development tools.

Extended Menu-Template Format

The extended menu-template format supports additional menu functionality. Like standard menu-template resources, extended menu-template resources have the RT_MENU resource type. The system distinguishes the two resource formats by the version number, which is the first member of the resource header.

An extended menu template consists of a MENUEX_TEMPLATE_HEADER structure followed by one more MENUEX_TEMPLATE_ITEM item definition structures.

Old Menu-Template Format

An old menu template (Microsoft Windows NT 3.51 and earlier) defines a menu, but does not support the new menu functionality. An old menu-template resource has the RT_MENU resource type.

An old menu template consists of a MENUITEMTEMPLATEHEADER structure followed by one or more MENUITEMTEMPLATE structures.

Loading a Menu-Template Resource

To load a menu-template resource, use the LoadMenu function, specifying a handle to the module that contains the resource and the menu template's identifier. The LoadMenu function returns a menu handle that you can use to assign the menu to a window. This window becomes the menu's owner window, receiving all the messages generated by the menu.

To create a menu from a menu template that is already in memory, use the LoadMenuIndirect function. This is useful if your application generates menu templates dynamically.

To assign a menu to a window, use the SetMenu function or specify the menu's handle in the hMenu parameter of the CreateWindowEx function when creating a window. Another way you can assign a menu to a window is to specify a menu template when you register a window class; the template identifies the specified menu as the class menu for that window class.

To have the system automatically assign a specific menu to a window, specify the menu's template when you register the window's class. The template identifies the specified menu as the class menu for that window class. Then, when you create a window of the specified class, the system automatically assigns the specified menu to the window.

You cannot assign a menu to a window that is a child window.

To create a class menu, include the identifier of the menu-template resource as the lpszMenuName member of a WNDCLASS structure and then pass a pointer to the structure to the RegisterClass function.

Creating a Class Menu

The following example shows how to create a class menu for an application, create a window that uses the class menu, and process menu commands in the window procedure.

Following is the relevant portion of the application's header file:

// Menu-template resource identifier 
 
#define IDM_MYMENURESOURCE   3

Following are the relevant portions of the application itself:

HINSTANCE hinst; 
 
int APIENTRY WinMain(HINSTANCE hinstance, HINSTANCE hPrevInstance, LPSTR lpCmdLine, int nCmdShow) 
{ 
    MSG msg = { };  // message 
    WNDCLASS wc;    // windowclass data 
    HWND hwnd;      // handle to the main window 
 
    // Create the window class for the main window. Specify 
    // the identifier of the menu-template resource as the 
    // lpszMenuName member of the WNDCLASS structure to create 
    // the class menu. 
 
    wc.style = 0; 
    wc.lpfnWndProc = (WNDPROC) MainWndProc; 
    wc.cbClsExtra = 0; 
    wc.cbWndExtra = 0; 
    wc.hInstance = hinstance; 
    wc.hIcon = LoadIcon(NULL, IDI_APPLICATION); 
    wc.hCursor = LoadCursor(NULL, IDC_ARROW); 
    wc.hbrBackground = GetStockObject(WHITE_BRUSH); 
    wc.lpszMenuName =  MAKEINTRESOURCE(IDM_MYMENURESOURCE); 
    wc.lpszClassName = "MainWClass"; 
 
    if (!RegisterClass(&wc)) 
        return FALSE; 
 
    hinst = hinstance; 
 
    // Create the main window. Set the hmenu parameter to NULL so 
    // that the system uses the class menu for the window. 
 
    hwnd = CreateWindow("MainWClass", "Sample Application", 
        WS_OVERLAPPEDWINDOW, CW_USEDEFAULT, CW_USEDEFAULT, 
        CW_USEDEFAULT, CW_USEDEFAULT, NULL, NULL, hinstance, 
        NULL); 
 
    if (hwnd == NULL) 
        return FALSE; 
 
    // Make the window visible and send a WM_PAINT message to the 
    // window procedure. 
 
    ShowWindow(hwnd, nCmdShow); 
    UpdateWindow(hwnd); 
 
    // Start the main message loop. 
 
    while (GetMessage(&msg, NULL, 0, 0)) 
    { 
        TranslateMessage(&msg); 
        DispatchMessage(&msg); 
    } 
    return msg.wParam; 
        UNREFERENCED_PARAMETER(hPrevInstance); 
} 
 
 
LRESULT APIENTRY MainWndProc(HWND hwnd, UINT uMsg, WPARAM wParam, LPARAM lParam) 
{ 
 
    switch (uMsg) 
    { 
        // Process other window messages. 
 
        case WM_COMMAND: 
 
            // Test for the identifier of a command item. 
 
            switch(LOWORD(wParam)) 
            { 
                case IDM_FI_OPEN: 
                    DoFileOpen();   // application-defined 
                    break; 
 
                case IDM_FI_CLOSE: 
                    DoFileClose();  // application-defined 
                    break; 
                // Process other menu commands. 
 
                default: 
                    break; 
 
            } 
            return 0; 
 
        // Process other window messages. 
 
        default: 
            return DefWindowProc(hwnd, uMsg, wParam, lParam); 
    } 
    return NULL; 
} 

Creating a Shortcut Menu

To use a shortcut menu in an application, pass its handle to the TrackPopupMenuEx function. An application typically calls TrackPopupMenuEx in a window procedure in response to a user-generated message, such as WM_LBUTTONDOWN or WM_KEYDOWN.

In addition to the pop-up menu handle, TrackPopupMenuEx requires that you specify a handle to the owner window, the position of the shortcut menu (in screen coordinates), and the mouse button that the user can use to choose an item.

The older TrackPopupMenu function is still supported, but new applications should use the TrackPopupMenuEx function. The TrackPopupMenuEx function requires the same parameters as TrackPopupMenu, but also lets you specify a portion of the screen that the menu should not obscure. An application typically calls these functions in a window procedure when processing the WM_CONTEXTMENU message.

You can specify the position of a shortcut menu by providing x- and y-coordinates along with the TPM_CENTERALIGN, TPM_LEFTALIGN, or TPM_RIGHTALIGN flag. The flag specifies the position of the shortcut menu relative to the x- and y-coordinates.

You should permit the user to choose an item from a shortcut menu by using the same mouse button used to display the menu. To do this, specify either TPM_LEFTBUTTON or TPM_RIGHTBUTTON flag to indicate which mouse button the user can use to choose a menu item.

Processing the WM_CONTEXTMENU Message

The WM_CONTEXTMENU message is generated when an application's window procedure passes the WM_RBUTTONUP or WM_NCRBUTTONUP message to the DefWindowProc function. The application can process this message to display a shortcut menu appropriate to a specific portion of its screen. If the application does not display a shortcut menu, it should pass the message to DefWindowProc for default handling.

Following is an example of WM_CONTEXTMENU message processing as it might appear in an application's window procedure. The low-order and high-order words of the lParam parameter specify the screen coordinates of the mouse when the right mouse button is released (note that these coordinates can take negative values on systems with multiple monitors). The application-defined OnContextMenu function returns TRUE if it displays a context menu, or FALSE if it does not.

case WM_CONTEXTMENU: 
    if (!OnContextMenu(hwnd, GET_X_LPARAM(lParam),
              GET_Y_LPARAM(lParam))) 
        return DefWindowProc(hwnd, uMsg, wParam, lParam); 
    break; 

The following application-defined OnContextMenu function displays a shortcut menu if the specified mouse position is within the window's client area. A more sophisticated function might display one of several different menus, depending on which portion of the client area is specified. To actually display the shortcut menu, this example calls an application-defined function called DisplayContextMenu. For a description of this function, see Displaying a Shortcut Menu.

BOOL WINAPI OnContextMenu(HWND hwnd, int x, int y) 
{ 
    RECT rc;                    // client area of window 
    POINT pt = { x, y };        // location of mouse click 
 
    // Get the bounding rectangle of the client area. 
 
    GetClientRect(hwnd, &rc); 
 
    // Convert the mouse position to client coordinates. 
 
    ScreenToClient(hwnd, &pt); 
 
    // If the position is in the client area, display a  
    // shortcut menu. 
 
    if (PtInRect(&rc, pt)) 
    { 
        ClientToScreen(hwnd, &pt); 
        DisplayContextMenu(hwnd, pt); 
        return TRUE; 
    } 
 
    // Return FALSE if no menu is displayed. 
 
    return FALSE; 
} 

Creating a Shortcut Font-Attributes Menu

The example in this section contains portions of code from an application that creates and displays a shortcut menu that enables the user to set fonts and font attributes. The application displays the menu in the client area of its main window whenever the user clicks the left mouse button.

Here is the menu template for the shortcut menu that is provided in the application's resource-definition file.

PopupMenu MENU 
BEGIN 
  POPUP "Dummy Popup" 
    BEGIN 
      POPUP "Fonts" 
        BEGIN 
          MENUITEM "Courier",     IDM_FONT_COURIER 
          MENUITEM "Times Roman", IDM_FONT_TMSRMN 
          MENUITEM "Swiss",       IDM_FONT_SWISS 
          MENUITEM "Helvetica",   IDM_FONT_HELV 
          MENUITEM "Old English", IDM_FONT_OLDENG 
        END 
      POPUP "Sizes" 
        BEGIN 
          MENUITEM "7",  IDM_SIZE_7 
          MENUITEM "8",  IDM_SIZE_8 
          MENUITEM "9",  IDM_SIZE_9 
          MENUITEM "10", IDM_SIZE_10 
          MENUITEM "11", IDM_SIZE_11 
          MENUITEM "12", IDM_SIZE_12 
          MENUITEM "14", IDM_SIZE_14 
        END 
      POPUP "Styles" 
        BEGIN 
          MENUITEM "Bold",        IDM_STYLE_BOLD 
          MENUITEM "Italic",      IDM_STYLE_ITALIC 
          MENUITEM "Strike Out",  IDM_STYLE_SO 
          MENUITEM "Superscript", IDM_STYLE_SUPER 
          MENUITEM "Subscript",   IDM_STYLE_SUB 
        END 
    END 
 
END 

The following example gives the window procedure and supporting functions used to create and display the shortcut menu.

LRESULT APIENTRY MenuWndProc(HWND hwnd, UINT uMsg, WPARAM wParam, LPARAM lParam) 
{ 
    RECT rc;    // client area             
    POINT pt;   // location of mouse click  
 
    switch (uMsg) 
    { 
        case WM_LBUTTONDOWN: 
 
            // Get the bounding rectangle of the client area. 
 
            GetClientRect(hwnd, (LPRECT) &rc); 
 
            // Get the client coordinates for the mouse click.  
 
            pt.x = GET_X_LPARAM(lParam); 
            pt.y = GET_Y_LPARAM(lParam); 
 
            // If the mouse click took place inside the client 
            // area, execute the application-defined function 
            // that displays the shortcut menu. 
 
            if (PtInRect((LPRECT) &rc, pt)) 
                HandlePopupMenu(hwnd, pt); 
            break; 
        // Process other window messages.  
 
        default: 
            return DefWindowProc(hwnd, uMsg, wParam, lParam); 
    } 
    return NULL; 
} 
 
 
VOID APIENTRY HandlePopupMenu(HWND hwnd, POINT pt) 
{ 
    HMENU hmenu;            // menu template          
    HMENU hmenuTrackPopup;  // shortcut menu   
 
    //  Load the menu template containing the shortcut menu from the 
    //  application's resources. 
 
    hmenu = LoadMenu(hinst, "PopupMenu"); 
    if (hmenu == NULL) 
        return; 
 
    // Get the first shortcut menu in the menu template. This is the 
    // menu that TrackPopupMenu displays. 
 
    hmenuTrackPopup = GetSubMenu(hmenu, 0); 
 
    // TrackPopup uses screen coordinates, so convert the 
    // coordinates of the mouse click to screen coordinates. 
 
    ClientToScreen(hwnd, (LPPOINT) &pt); 
 
    // Draw and track the shortcut menu.  
 
    TrackPopupMenu(hmenuTrackPopup, TPM_LEFTALIGN | TPM_LEFTBUTTON, 
        pt.x, pt.y, 0, hwnd, NULL); 
 
    // Destroy the menu. 
 
    DestroyMenu(hmenu); 
} 

Displaying a Shortcut Menu

The function shown in the following example displays a shortcut menu.

The application includes a menu resource identified by the string "ShortcutExample." The menu bar simply contains a menu name. The application uses the TrackPopupMenu function to display the menu associated with this menu item. (The menu bar itself is not displayed because TrackPopupMenu requires a handle to a menu, submenu, or shortcut menu.)

VOID APIENTRY DisplayContextMenu(HWND hwnd, POINT pt) 
{ 
    HMENU hmenu;            // top-level menu 
    HMENU hmenuTrackPopup;  // shortcut menu 
 
    // Load the menu resource. 
 
    if ((hmenu = LoadMenu(hinst, "ShortcutExample")) == NULL) 
        return; 
 
    // TrackPopupMenu cannot display the menu bar so get 
    // a handle to the first shortcut menu. 
 
    hmenuTrackPopup = GetSubMenu(hmenu, 0); 
 
    // Display the shortcut menu. Track the right mouse 
    // button. 
 
    TrackPopupMenu(hmenuTrackPopup, 
            TPM_LEFTALIGN | TPM_RIGHTBUTTON, 
            pt.x, pt.y, 0, hwnd, NULL); 
 
    // Destroy the menu. 
 
    DestroyMenu(hmenu); 
} 

Using Menu-Item Bitmaps

The system can use a bitmap instead of a text string to display a menu item. To use a bitmap, you must set the MIIM_BITMAP flag for the menu item and specify a handle to the bitmap that the system should display for the menu item in the hbmpItem member of the MENUITEMINFO structure. This section describes how to use bitmaps for menu items.

Setting the Bitmap Type Flag

The MIIM_BITMAP or MF_BITMAP flag tells the system to use a bitmap rather than a text string to display a menu item. A menu item's MIIM_BITMAP or MF_BITMAP flag must be set at run time; you cannot set it in the resource-definition file.

For new applications, you can use the SetMenuItemInfo or InsertMenuItem function to set the MIIM_BITMAP type flag. To change a menu item from a text item to a bitmap item, use SetMenuItemInfo. To add a new bitmap item to a menu, use the InsertMenuItem function.

Applications written for earlier versions of the system can continue to use the ModifyMenu, InsertMenu, or AppendMenu functions to set the MF_BITMAP flag. To change a menu item from a text string item to a bitmap item, use ModifyMenu. To add a new bitmap item to a menu, use the MF_BITMAP flag with the InsertMenu or AppendMenu function.

Creating the Bitmap

When you set the MIIM_BITMAP or MF_BITMAP type flag for a menu item, you must also specify a handle to the bitmap that the system should display for the menu item. You can provide the bitmap as a bitmap resource or create the bitmap at run time. If you use a bitmap resource, you can use the LoadBitmap function to load the bitmap and obtain its handle.

To create the bitmap at run time, use Windows Graphics Device Interface (GDI) functions. GDI provides several ways to create a bitmap at run time, but developers typically use the following method:

  1. Use the CreateCompatibleDC function to create a device context compatible with the device context used by the application's main window.
  2. Use the CreateCompatibleBitmap function to create a bitmap compatible with the application's main window or use the CreateBitmap function to create a monochrome bitmap.
  3. Use the SelectObject function to select the bitmap into the compatible device context.
  4. Use GDI drawing functions, such as Ellipse and LineTo, to draw an image into the bitmap.

For more information, see Bitmaps.

Adding Lines and Graphs to a Menu

The following code sample shows how to create a menu that contains menu-item bitmaps. It creates two menus. The first is a Chart menu that contains three menu-item bitmaps: a pie chart, a line chart, and a bar chart. The example demonstrates how to load these bitmaps from the application's resource file, and then use the CreatePopupMenu and AppendMenu functions to create the menu and menu items.

The second menu is a Lines menu. It contains bitmaps showing the line styles provided by the predefined pen in the system. The line-style bitmaps are created at run time by using GDI functions.

Here are the definitions of the bitmap resources in the application's resource-definition file.

PIE BITMAP pie.bmp
LINE BITMAP line.bmp
BAR BITMAP bar.bmp

Here are the relevant portions of the application's header file.

// Menu-item identifiers 
 
#define IDM_SOLID       PS_SOLID 
#define IDM_DASH        PS_DASH 
#define IDM_DASHDOT     PS_DASHDOT 
#define IDM_DASHDOTDOT  PS_DASHDOTDOT 
 
#define IDM_PIE  1 
#define IDM_LINE 2 
#define IDM_BAR  3 
 
// Line-type flags  
 
#define SOLID       0 
#define DOT         1 
#define DASH        2 
#define DASHDOT     3 
#define DASHDOTDOT  4 
 
// Count of pens  
 
#define CPENS 5 
 
// Chart-type flags  
 
#define PIE  1 
#define LINE 2 
#define BAR  3 
 
// Function prototypes  
 
LRESULT APIENTRY MainWndProc(HWND, UINT, WPARAM, LPARAM); 
VOID MakeChartMenu(HWND); 
VOID MakeLineMenu(HWND, HPEN, HBITMAP); 

The following example shows how menus and menu-item bitmaps are created in an application.

LRESULT APIENTRY MainWndProc(HWND hwnd, UINT uMsg, WPARAM wParam, LPARAM lParam) 
{ 
 
    static HPEN hpen[CPENS]; 
    static HBITMAP hbmp[CPENS]; 
    int i; 
 
    switch (uMsg) 
    { 
        case WM_CREATE: 
 
            // Create the Chart and Line menus.  
 
            MakeChartMenu(hwnd); 
            MakeLineMenu(hwnd, hpen, hbmp); 
            return 0; 
 
        // Process other window messages. 
 
        case WM_DESTROY: 
 
            for (i = 0; i < CPENS; i++) 
            { 
                DeleteObject(hbmp[i]); 
                DeleteObject(hpen[i]); 
            } 
 
            PostQuitMessage(0); 
            break; 
 
        default: 
            return DefWindowProc(hwnd, uMsg, wParam, lParam); 
    } 
    return NULL; 
} 
 
VOID MakeChartMenu(HWND hwnd) 
{ 
    HBITMAP hbmpPie;    // handle to pie chart bitmap   
    HBITMAP hbmpLine;   // handle to line chart bitmap  
    HBITMAP hbmpBar;    // handle to bar chart bitmap   
    HMENU hmenuMain;    // handle to main menu          
    HMENU hmenuChart;   // handle to Chart menu  
 
    // Load the pie, line, and bar chart bitmaps from the 
    // resource-definition file. 
 
    hbmpPie = LoadBitmap(hinst, MAKEINTRESOURCE(PIE)); 
    hbmpLine = LoadBitmap(hinst, MAKEINTRESOURCE(LINE)); 
    hbmpBar = LoadBitmap(hinst, MAKEINTRESOURCE(BAR)); 
 
    // Create the Chart menu and add it to the menu bar. 
    // Append the Pie, Line, and Bar menu items to the Chart 
    // menu. 
 
    hmenuMain = GetMenu(hwnd); 
    hmenuChart = CreatePopupMenu(); 
    AppendMenu(hmenuMain, MF_STRING | MF_POPUP, (UINT) hmenuChart, 
        "Chart"); 
    AppendMenu(hmenuChart, MF_BITMAP, IDM_PIE, (LPCTSTR) hbmpPie); 
    AppendMenu(hmenuChart, MF_BITMAP, IDM_LINE, 
        (LPCTSTR) hbmpLine); 
    AppendMenu(hmenuChart, MF_BITMAP, IDM_BAR, (LPCTSTR) hbmpBar); 
 
    return; 
} 
 
VOID MakeLineMenu(HWND hwnd, HPEN phpen, HBITMAP phbmp) 
{ 
    HMENU hmenuLines;       // handle to Lines menu      
    HMENU hmenu;            // handle to main menu              
    COLORREF crMenuClr;     // menu-item background color       
    HBRUSH hbrBackground;   // handle to background brush       
    HBRUSH hbrOld;          // handle to previous brush         
    WORD wLineX;            // width of line bitmaps            
    WORD wLineY;            // height of line bitmaps           
    HDC hdcMain;            // handle to main window's DC       
    HDC hdcLines;           // handle to compatible DC          
    HBITMAP hbmpOld;        // handle to previous bitmap        
    int i;                  // loop counter                     
 
    // Create the Lines menu. Add it to the menu bar.  
 
    hmenu = GetMenu(hwnd); 
    hmenuLines = CreatePopupMenu(); 
    AppendMenu(hmenu, MF_STRING | MF_POPUP, 
        (UINT) hmenuLines, "&Lines"); 
 
    // Create a brush for the menu-item background color.  
 
    crMenuClr = GetSysColor(COLOR_MENU); 
    hbrBackground = CreateSolidBrush(crMenuClr); 
 
    // Create a compatible device context for the line bitmaps, 
    // and then select the background brush into it. 
 
    hdcMain = GetDC(hwnd); 
    hdcLines = CreateCompatibleDC(hdcMain); 
    hbrOld = SelectObject(hdcLines, hbrBackground); 
 
    // Get the dimensions of the check-mark bitmap. The width of 
    // the line bitmaps will be five times the width of the 
    // check-mark bitmap. 
 
    wLineX = GetSystemMetrics(SM_CXMENUCHECK) * (WORD) 5; 
    wLineY = GetSystemMetrics(SM_CYMENUCHECK); 
 
    // Create the bitmaps and select them, one at a time, into the 
    // compatible device context. Initialize each bitmap by 
    // filling it with the menu-item background color. 
 
    for (i = 0; i < CPENS; i++) 
    { 
        phbmp[i] = CreateCompatibleBitmap(hdcMain, wLineX, wLineY); 
        if (i == 0) 
            hbmpOld = SelectObject(hdcLines, phbmp[i]); 
        else 
            SelectObject(hdcLines, phbmp[i]); 
        ExtFloodFill(hdcLines, 0, 0, crMenuClr, FLOODFILLBORDER); 
    } 
 
    // Create the pens.  
 
    phpen[0] = CreatePen(PS_SOLID, 1, RGB(0, 0, 0)); 
    phpen[1] = CreatePen(PS_DOT, 1, RGB(0, 0, 0)); 
    phpen[2] = CreatePen(PS_DASH, 1, RGB(0, 0, 0)); 
    phpen[3] = CreatePen(PS_DASHDOT, 1, RGB(0, 0, 0)); 
    phpen[4] = CreatePen(PS_DASHDOTDOT, 1, RGB(0, 0, 0)); 
 
    // Select a pen and a bitmap into the compatible device 
    // context, draw a line into the bitmap, and then append 
    // the bitmap as an item in the Lines menu. 
 
    for (i = 0; i < CPENS; i++) 
    { 
        SelectObject(hdcLines, phbmp[i]); 
        SelectObject(hdcLines, phpen[i]); 
        MoveToEx(hdcLines, 0, wLineY / 2, NULL); 
        LineTo(hdcLines, wLineX, wLineY / 2); 
        AppendMenu(hmenuLines, MF_BITMAP, i + 1, 
            (LPCTSTR) phbmp[i]); 
    } 
 
    // Release the main window's device context and destroy the 
    // compatible device context. Also, destroy the background 
    // brush. 
 
    ReleaseDC(hwnd, hdcMain); 
    SelectObject(hdcLines, hbrOld); 
    DeleteObject(hbrBackground); 
    SelectObject(hdcLines, hbmpOld); 
    DeleteDC(hdcLines); 
 
    return; 
} 

Example of Menu-Item Bitmaps

The example in this topic creates two menus, each containing several bitmap menu items. For each menu, the application adds a corresponding menu name to the main window's menu bar.

The first menu contains menu items showing each of three chart types: pie, line, and bar. The bitmaps for these menu items are defined as resources and are loaded by using the LoadBitmap function. Associated with this menu is a "Chart" menu name on the menu bar.

The second menu contains menu items showing each of the five line styles used with the CreatePen function: PS_SOLID, PS_DASH, PS_DOT, PS_DASHDOT, and PS_DASHDOTDOT. The application creates the bitmaps for these menu items at run time using GDI drawing functions. Associated with this menu is a Lines menu name on the menu bar.

Defined in the application's window procedure are two static arrays of bitmap handles. One array contains the handles of the three bitmaps used for the Chart menu. The other contains the handles of the five bitmaps used for the Lines menu. When processing the WM_CREATE message, the window procedure loads the chart bitmaps, creates the line bitmaps, and then adds the corresponding menu items. When processing the WM_DESTROY message, the window procedure deletes all of the bitmaps.

Following are the relevant portions of the application's header file.

// Menu-item identifiers 
 
#define IDM_PIE         1 
#define IDM_LINE        2 
#define IDM_BAR         3 
 
#define IDM_SOLID       4 
#define IDM_DASH        5 
#define IDM_DASHDOT     6 
#define IDM_DASHDOTDOT  7 
 
// Number of items on the Chart and Lines menus 
 
#define C_LINES         5 
#define C_CHARTS        3 
 
// Bitmap resource identifiers 
 
#define IDB_PIE         1 
#define IDB_LINE        2 
#define IDB_BAR         3 
 
// Dimensions of the line bitmaps 
 
#define CX_LINEBMP      40 
#define CY_LINEBMP      10 

Following are the relevant portions of the window procedure. The window procedure performs most of its initialization by calling the application-defined LoadChartBitmaps, CreateLineBitmaps, and AddBitmapMenu functions, described later in this topic.

LRESULT CALLBACK MainWindowProc( 
        HWND hwnd, 
        UINT uMsg, 
        WPARAM wParam, 
        LPARAM lParam 
        ) 
{ 
    static HBITMAP aHbmLines[C_LINES]; 
    static HBITMAP aHbmChart[C_CHARTS]; 
    int i; 
 
    switch (uMsg) 
    { 
        case WM_CREATE: 
 
             // Call application-defined functions to load the 
             // bitmaps for the Chart menu and create those for 
             // the Lines menu. 
 
            LoadChartBitmaps(aHbmChart); 
            CreateLineBitmaps(aHbmLines); 
 
             // Call an application-defined function to create 
             // menus containing the bitmap menu items. The function 
             // also adds a menu name to the window's menu bar. 
 
            AddBitmapMenu( 
                    hwnd,      // menu bar's owner window 
                    "&Chart",  // text of menu name on menu bar 
                    IDM_PIE,   // ID of first item on menu 
                    aHbmChart, // array of bitmap handles 
                    C_CHARTS   // number of items on menu 
                    ); 
            AddBitmapMenu(hwnd, "&Lines", IDM_SOLID, 
                    aHbmLines, C_LINES); 
            break; 
 
        case WM_DESTROY: 
            for (i = 0; i < C_LINES; i++) 
                DeleteObject(aHbmLines[i]); 
            for (i = 0; i < C_CHARTS; i++) 
                DeleteObject(aHbmChart[i]); 
            PostQuitMessage(0); 
            break; 
 
        // Process additional messages here. 
 
        default: 
            return (DefWindowProc(hwnd, uMsg, wParam, lParam)); 
    } 
    return 0; 
} 

The application-defined LoadChartBitmaps function loads the bitmap resources for the chart menu by calling the LoadBitmap function, as follows.

VOID WINAPI LoadChartBitmaps(HBITMAP *paHbm) 
{ 
    paHbm[0] = LoadBitmap(g_hinst, MAKEINTRESOURCE(IDB_PIE)); 
    paHbm[1] = LoadBitmap(g_hinst, MAKEINTRESOURCE(IDB_LINE)); 
    paHbm[2] = LoadBitmap(g_hinst, MAKEINTRESOURCE(IDB_BAR)); 
} 

The application-defined CreateLineBitmaps function creates the bitmaps for the Lines menu by using GDI drawing functions. The function creates a memory device context (DC) with the same properties as the desktop window's DC. For each line style, the function creates a bitmap, selects it into the memory DC, and draws in it.

VOID WINAPI CreateLineBitmaps(HBITMAP *paHbm) 
{ 
    HWND hwndDesktop = GetDesktopWindow(); 
    HDC hdcDesktop = GetDC(hwndDesktop); 
    HDC hdcMem = CreateCompatibleDC(hdcDesktop); 
    COLORREF clrMenu = GetSysColor(COLOR_MENU); 
    HBRUSH hbrOld; 
    HPEN hpenOld; 
    HBITMAP hbmOld; 
    int fnDrawMode; 
    int i; 
 
     // Create a brush using the menu background color, 
     // and select it into the memory DC. 
 
    hbrOld = SelectObject(hdcMem, CreateSolidBrush(clrMenu)); 
 
     // Create the bitmaps. Select each one into the memory 
     // DC that was created and draw in it. 
 
    for (i = 0; i < C_LINES; i++) 
    { 
        // Create the bitmap and select it into the DC. 
 
        paHbm[i] = CreateCompatibleBitmap(hdcDesktop, 
                CX_LINEBMP, CY_LINEBMP); 
        hbmOld = SelectObject(hdcMem, paHbm[i]); 
 
        // Fill the background using the brush. 
 
        PatBlt(hdcMem, 0, 0, CX_LINEBMP, CY_LINEBMP, PATCOPY); 
 
        // Create the pen and select it into the DC. 
 
        hpenOld = SelectObject(hdcMem, 
                CreatePen(PS_SOLID + i, 1, RGB(0, 0, 0))); 
 
         // Draw the line. To preserve the background color where 
         // the pen is white, use the R2_MASKPEN drawing mode. 
 
        fnDrawMode = SetROP2(hdcMem, R2_MASKPEN); 
        MoveToEx(hdcMem, 0, CY_LINEBMP / 2, NULL); 
        LineTo(hdcMem, CX_LINEBMP, CY_LINEBMP / 2); 
        SetROP2(hdcMem, fnDrawMode); 
 
        // Delete the pen, and select the old pen and bitmap. 
 
        DeleteObject(SelectObject(hdcMem, hpenOld)); 
        SelectObject(hdcMem, hbmOld); 
    } 
 
    // Delete the brush and select the original brush. 
 
    DeleteObject(SelectObject(hdcMem, hbrOld)); 
 
    // Delete the memory DC and release the desktop DC. 
 
    DeleteDC(hdcMem); 
    ReleaseDC(hwndDesktop, hdcDesktop); 
} 

The application-defined AddBitmapMenu function creates a menu and adds the specified number of bitmap menu items to it. Then it adds a corresponding menu name to the specified window's menu bar.

VOID WINAPI AddBitmapMenu( 
        HWND hwnd,          // window that owned the menu bar 
        LPSTR lpszText,     // text of menu name on menu bar 
        UINT uID,           // ID of first bitmap menu item 
        HBITMAP *paHbm,     // bitmaps for the menu items 
        int cItems)         // number bitmap menu items 
{ 
    HMENU hmenuBar = GetMenu(hwnd); 
    HMENU hmenuPopup = CreatePopupMenu(); 
    MENUITEMINFO mii; 
    int i; 
 
    // Add the bitmap menu items to the menu. 
 
    for (i = 0; i < cItems; i++) 
    { 
        mii.fMask = MIIM_ID | MIIM_BITMAP | MIIM_DATA; 
        mii.wID = uID + i; 
        mii.hbmpItem = &paHbm[i]; 
        InsertMenuItem(hmenuPopup, i, TRUE, &mii); 
    } 
 
    // Add a menu name to the menu bar. 
 
    mii.fMask = MIIM_STRING | MIIM_DATA | MIIM_SUBMENU; 
    mii.fType = MFT_STRING; 
    mii.hSubMenu = hmenuPopup; 
    mii.dwTypeData = lpszText; 
    InsertMenuItem(hmenuBar, 
        GetMenuItemCount(hmenuBar), TRUE, &mii); 
} 

Creating Owner-Drawn Menu Items

If you need complete control over the appearance of a menu item, you can use an owner-drawn menu item in your application. This section describes the steps involved in creating and using an owner-drawn menu item.

Setting the Owner-Drawn Flag

You cannot define an owner-drawn menu item in your application's resource-definition file. Instead, you must create a new menu item or modify an existing one by using the MFT_OWNERDRAW menu flag.

You can use the InsertMenuItem or SetMenuItemInfo function to specify an owner-drawn menu item. Use InsertMenuItem to insert a new menu item at the specified position in a menu bar or menu. Use SetMenuItemInfo to change the contents of a menu.

When calling these two functions, you must specify a pointer to a MENUITEMINFO structure, which specifies the properties of the new menu item or the properties you want to change for an existing menu item. To make an item an owner-drawn item, specify the MIIM_FTYPE value for the fMask member and the MFT_OWNERDRAW value for the fType member.

By setting the appropriate members of the MENUITEMINFO structure, you can associate an application-defined value, which is called item data, with each menu item. To do so, specify the MIIM_DATA value for the fMask member and the application-defined value for the dwItemData member.

You can use item data with any type of menu item, but it is particularly useful for owner-drawn items. For example, suppose a structure contains information used to draw a menu item. An application might use the item data for a menu item to store a pointer to the structure. The item data is sent to the menu's owner window with the WM_MEASUREITEM and WM_DRAWITEM messages. To retrieve the item data for a menu at any time, use the GetMenuItemInfo function.

Applications written for earlier versions of the system can continue to call AppendMenu, InsertMenu, or ModifyMenu to assign the MF_OWNERDRAW flag to an owner-drawn menu item.

When you call any of these three functions, you can pass a value as the lpNewItem parameter. This value can represent any information that is meaningful to your application, and that will be available to your application when the item is to be displayed. For example, the value could contain a pointer to a structure; the structure, in turn, might contain a text string and a handle to the logical font your application will use to draw the string.

Owner-Drawn Menus and the WM_MEASUREITEM Message

Before the system displays an owner-drawn menu item for the first time, it sends the WM_MEASUREITEM message to the window procedure of the window that owns the item's menu. This message contains a pointer to a MEASUREITEMSTRUCT structure that identifies the item and contains the item data that an application may have assigned to it. The window procedure must fill the itemWidth and itemHeight members of the structure before returning from processing the message. The system uses the information in these members when creating the bounding rectangle in which an application draws the menu item. It also uses the information to detect when the user chooses the item.

Owner-Drawn Menus and the WM_DRAWITEM Message

Whenever the item must be drawn (for example, when it is first displayed or when the user selects it), the system sends the WM_DRAWITEM message to the window procedure of the menu's owner window. This message contains a pointer to a DRAWITEMSTRUCT structure, which contains information about the item, including the item data that an application may have assigned to it. In addition, DRAWITEMSTRUCT contains flags that indicate the state of the item (such as whether it is grayed or selected) as well as a bounding rectangle and a device context that the application uses to draw the item.

An application must do the following while processing the WM_DRAWITEM message:

  • Determine the type of drawing that is necessary. To do so, check the itemAction member of the DRAWITEMSTRUCT structure.
  • Draw the menu item appropriately, using the bounding rectangle and device context obtained from the DRAWITEMSTRUCT structure. The application must draw only within the bounding rectangle. For performance reasons, the system does not clip portions of the image that are drawn outside the rectangle.
  • Restore all GDI objects selected for the menu item's device context.

If the user selects the menu item, the system sets the itemAction member of the DRAWITEMSTRUCT structure to the ODA_SELECT value and sets the ODS_SELECTED value in the itemState member. This is an application's cue to redraw the menu item to indicate that it is selected.

Owner-Drawn Menus and the WM_MENUCHAR Message

Menus other than owner-drawn menus can specify a menu mnemonic by inserting an underscore next to a character in the menu string. This allows the user to select the menu by pressing ALT and pressing the menu mnemonic character. In owner-drawn menus, however, you cannot specify a menu mnemonic in this manner. Instead, your application must process the WM_MENUCHAR message to provide owner-drawn menus with menu mnemonics.

The WM_MENUCHAR message is sent when the user types a menu mnemonic that does not match any of the predefined mnemonics of the current menu. The value contained in wParam specifies the ASCII character that corresponds to the key the user pressed with the ALT key. The low-order word of wParam specifies the type of the selected menu and can be one of the following values:

  • MF_POPUP if the current menu is a submenu.
  • MF_SYSMENU if the menu is the system menu.

The high-order word of wParam contains the menu handle to the current menu. The window with the owner-drawn menus can process WM_MENUCHAR as follows:

   case WM_MENUCHAR:
      nIndex = Determine index of menu item to be selected from
               character that was typed and handle to the current
               menu.
      return MAKELRESULT(nIndex, 2);

The two in the high-order word of the return value informs the system that the low-order word of the return value contains the zero-based index of the menu item to be selected.

The following constants correspond to the possible return values from the WM_MENUCHAR message.

Constant Value Meaning
MNC_IGNORE 0 The system should discard the character the user pressed and create a short beep on the system speaker.
MNC_CLOSE 1 The system should close the active menu.
MNC_EXECUTE 2 The system should choose the item specified in the low-order word of the return value. The owner window receives a WM_COMMAND message.
MNC_SELECT 3 The system should select the item specified in the low-order word of the return value.

 

Setting Fonts for Menu-Item Text Strings

This topic contains an example from an application that uses owner-drawn menu items in a menu. The menu contains items that set the attributes of the current font, and the items are displayed using the appropriate font attribute.

Here is how the menu is defined in the resource-definition file. Note that the strings for the Regular, Bold, Italic, and Underline menu items are assigned at run time, so their strings are empty in the resource-definition file.

MainMenu MENU 
BEGIN 
    POPUP   "&Character" 
    BEGIN 
        MENUITEM    "",    IDM_REGULAR 
        MENUITEM SEPARATOR 
        MENUITEM    "",    IDM_BOLD 
        MENUITEM    "",    IDM_ITALIC 
        MENUITEM    "",    IDM_ULINE 
    END 
END 

The application's window procedure processes the messages involved in using owner-drawn menu items. The application uses the WM_CREATE message to do the following:

  • Set the MF_OWNERDRAW flag for the menu items.
  • Set the text strings for the menu items.
  • Obtain handles of the fonts used to draw the items.
  • Obtain the text and background color values for selected menu items.

The text strings and font handles are stored in an array of application-defined MYITEM structures. The application-defined GetAFont function creates a font that corresponds to the specified font attribute and returns a handle to the font. The handles are destroyed during the processing of the WM_DESTROY message.

During the processing of the WM_MEASUREITEM message, the example gets the width and height of a menu-item string and copies these values into the MEASUREITEMSTRUCT structure. The system uses the width and height values to calculate the size of the menu.

During the processing of the WM_DRAWITEM message, the menu item's string is drawn with room left next to the string for the check-mark bitmap. If the user selects the item, the selected text and background colors are used to draw the item.

LRESULT APIENTRY MainWndProc(HWND hwnd, UINT uMsg, WPARAM wParam, LPARAM lParam) 
{ 
 
    typedef struct _MYITEM 
    { 
        HFONT hfont; 
        LPSTR psz; 
    } MYITEM;             // structure for item font and string  
 
    MYITEM *pmyitem;      // pointer to item's font and string        
    static MYITEM myitem[CITEMS];   // array of MYITEMS               
    static HMENU hmenu;             // handle to main menu            
    static COLORREF crSelText;  // text color of selected item        
    static COLORREF crSelBkgnd; // background color of selected item  
    COLORREF crText;            // text color of unselected item      
    COLORREF crBkgnd;           // background color unselected item   
    LPMEASUREITEMSTRUCT lpmis;  // pointer to item of data             
    LPDRAWITEMSTRUCT lpdis;     // pointer to item drawing data        
    HDC hdc;                    // handle to screen DC                
    SIZE size;                  // menu-item text extents             
    WORD wCheckX;               // check-mark width                   
    int nTextX;                 // width of menu item                 
    int nTextY;                 // height of menu item                
    int i;                      // loop counter                       
    HFONT hfontOld;             // handle to old font                 
    BOOL fSelected = FALSE;     // menu-item selection flag
    size_t * pcch;
    HRESULT hResult;           
 
    switch (uMsg) 
    { 
        case WM_CREATE: 
 
            // Modify the Regular, Bold, Italic, and Underline 
            // menu items to make them owner-drawn items. Associate 
            // a MYITEM structure with each item to contain the 
            // string for and font handle to each item. 
 
            hmenu = GetMenu(hwnd); 
            ModifyMenu(hmenu, IDM_REGULAR, MF_BYCOMMAND | 
                MF_CHECKED | MF_OWNERDRAW, IDM_REGULAR, 
                (LPTSTR) &myitem[REGULAR]); 
            ModifyMenu(hmenu, IDM_BOLD, MF_BYCOMMAND | 
                MF_OWNERDRAW, IDM_BOLD, (LPTSTR) &myitem[BOLD]); 
            ModifyMenu(hmenu, IDM_ITALIC, MF_BYCOMMAND | 
                MF_OWNERDRAW, IDM_ITALIC, 
                (LPTSTR) &myitem[ITALIC]); 
            ModifyMenu(hmenu, IDM_ULINE, MF_BYCOMMAND | 
                MF_OWNERDRAW, IDM_ULINE, (LPTSTR) &myitem[ULINE]); 
 
            // Retrieve each item's font handle and copy it into 
            // the hfont member of each item's MYITEM structure. 
            // Also, copy each item's string into the structures. 
 
            myitem[REGULAR].hfont = GetAFont(REGULAR); 
            myitem[REGULAR].psz = "Regular"; 
            myitem[BOLD].hfont = GetAFont(BOLD); 
            myitem[BOLD].psz = "Bold"; 
            myitem[ITALIC].hfont = GetAFont(ITALIC); 
            myitem[ITALIC].psz = "Italic"; 
            myitem[ULINE].hfont = GetAFont(ULINE); 
            myitem[ULINE].psz = "Underline"; 
 
            // Retrieve the text and background colors of the 
            // selected menu text. 
 
            crSelText = GetSysColor(COLOR_HIGHLIGHTTEXT); 
            crSelBkgnd = GetSysColor(COLOR_HIGHLIGHT); 
 
            return 0; 
 
        case WM_MEASUREITEM: 
 
            // Retrieve a device context for the main window.  
 
            hdc = GetDC(hwnd); 
 
            // Retrieve pointers to the menu item's 
            // MEASUREITEMSTRUCT structure and MYITEM structure. 
 
            lpmis = (LPMEASUREITEMSTRUCT) lParam; 
            pmyitem = (MYITEM *) lpmis->itemData; 
 
            // Select the font associated with the item into 
            // the main window's device context. 
 
            hfontOld = SelectObject(hdc, pmyitem->hfont); 
 
            // Retrieve the width and height of the item's string, 
            // and then copy the width and height into the 
            // MEASUREITEMSTRUCT structure's itemWidth and 
            // itemHeight members.
            
            hResult = StringCchLength(pmyitem->psz,STRSAFE_MAX_CCH, pcch);
            if (FAILED(hResult))
            {
            // Add code to fail as securely as possible.
                return;
            } 
 
            GetTextExtentPoint32(hdc, pmyitem->psz, 
                *pcch, &size); 
            lpmis->itemWidth = size.cx; 
            lpmis->itemHeight = size.cy; 
 
            // Select the old font back into the device context, 
            // and then release the device context. 
 
            SelectObject(hdc, hfontOld); 
            ReleaseDC(hwnd, hdc); 
 
            return TRUE; 
 
            break; 
 
        case WM_DRAWITEM: 
 
            // Get pointers to the menu item's DRAWITEMSTRUCT 
            // structure and MYITEM structure. 
 
            lpdis = (LPDRAWITEMSTRUCT) lParam; 
            pmyitem = (MYITEM *) lpdis->itemData; 
 
            // If the user has selected the item, use the selected 
            // text and background colors to display the item. 
 
            if (lpdis->itemState & ODS_SELECTED) 
            { 
                crText = SetTextColor(lpdis->hDC, crSelText); 
                crBkgnd = SetBkColor(lpdis->hDC, crSelBkgnd); 
                fSelected = TRUE; 
            } 
 
            // Remember to leave space in the menu item for the 
            // check-mark bitmap. Retrieve the width of the bitmap 
            // and add it to the width of the menu item. 
 
            wCheckX = GetSystemMetrics(SM_CXMENUCHECK); 
            nTextX = wCheckX + lpdis->rcItem.left; 
            nTextY = lpdis->rcItem.top; 
 
            // Select the font associated with the item into the 
            // item's device context, and then draw the string. 
 
            hfontOld = SelectObject(lpdis->hDC, pmyitem->hfont);
            
            hResult = StringCchLength(pmyitem->psz,STRSAFE_MAX_CCH, pcch);
            if (FAILED(hResult))
            {
            // Add code to fail as securely as possible.
                return;
            } 
 
            ExtTextOut(lpdis->hDC, nTextX, nTextY, ETO_OPAQUE, 
                &lpdis->rcItem, pmyitem->psz, 
                *pcch, NULL); 
 
            // Select the previous font back into the device 
            // context. 
 
            SelectObject(lpdis->hDC, hfontOld); 
 
            // Return the text and background colors to their 
            // normal state (not selected). 
 
            if (fSelected) 
            { 
                SetTextColor(lpdis->hDC, crText); 
                SetBkColor(lpdis->hDC, crBkgnd); 
            } 
 
            return TRUE; 
 
        // Process other messages.  
 
        case WM_DESTROY: 
 
            // Destroy the menu items' font handles.  
 
            for (i = 0; i < CITEMS; i++) 
                DeleteObject(myitem[i].hfont); 
 
            PostQuitMessage(0); 
            break; 
 
        default: 
            return DefWindowProc(hwnd, uMsg, wParam, lParam); 
    } 
    return NULL; 
} 
 
HFONT GetAFont(int fnFont) 
{ 
    static LOGFONT lf;  // structure for font information  
 
    // Get a handle to the ANSI fixed-pitch font, and copy 
    // information about the font to a LOGFONT structure. 
 
    GetObject(GetStockObject(ANSI_FIXED_FONT), sizeof(LOGFONT), 
        &lf); 
 
    // Set the font attributes, as appropriate.  
 
    if (fnFont == BOLD) 
        lf.lfWeight = FW_BOLD; 
    else 
        lf.lfWeight = FW_NORMAL; 
 
    lf.lfItalic = (fnFont == ITALIC); 
    lf.lfItalic = (fnFont == ULINE); 
 
    // Create the font, and then return its handle.  
 
    return CreateFont(lf.lfHeight, lf.lfWidth, 
        lf.lfEscapement, lf.lfOrientation, lf.lfWeight, 
        lf.lfItalic, lf.lfUnderline, lf.lfStrikeOut, lf.lfCharSet, 
        lf.lfOutPrecision, lf.lfClipPrecision, lf.lfQuality, 
        lf.lfPitchAndFamily, lf.lfFaceName); 
} 

Example of Owner-Drawn Menu Items

The example in this topic uses owner-drawn menu items in a menu. The menu items select specific font attributes, and the application displays each menu item using a font that has the corresponding attribute. For example, the Italic menu item is displayed in an italic font. The Character menu name on the menu bar opens the menu.

The menu bar and drop-down menu are defined initially by an extended menu-template resource. Because a menu template cannot specify owner-drawn items, the menu initially contains four text menu items with the following strings: "Regular," "Bold," "Italic," and "Underline." The application's window procedure changes these to owner-drawn items when it processes the WM_CREATE message. When it receives the WM_CREATE message, the window procedure calls the application-defined OnCreate function, which performs the following steps for each menu item:

  • Allocates an application-defined MYITEM structure.
  • Gets the text of the menu item and saves it in the application-defined MYITEM structure.
  • Creates the font used to display the menu item and saves its handle in the application-defined MYITEM structure.
  • Changes the menu item type to MFT_OWNERDRAW and saves a pointer to the application-defined MYITEM structure as item data.

Because a pointer to each application-defined MYITEM structure is saved as item data, it is passed to the window procedure in conjunction with the WM_MEASUREITEM and WM_DRAWITEM messages for the corresponding menu item. The pointer is contained in the itemData member of both the MEASUREITEMSTRUCT and DRAWITEMSTRUCT structures.

A WM_MEASUREITEM message is sent for each owner-drawn menu item the first time it is displayed. The application processes this message by selecting the font for the menu item into a device context and then determining the space required to display the menu item text in that font. The font and menu item text are both specified by the menu item's MYITEM structure (the structure defined by the application). The application determines the size of the text by using the GetTextExtentPoint32 function.

The window procedure processes the WM_DRAWITEM message by displaying the menu item text in the appropriate font. The font and menu item text are both specified by the menu item's MYITEM structure. The application selects text and background colors appropriate to the menu item's state.

The window procedure processes the WM_DESTROY message to destroy fonts and free memory. The application deletes the font and frees the application-defined MYITEM structure for each menu item.

The following are the relevant portions of the application's header file.

// Menu-item identifiers for the Character menu 
 
#define IDM_CHARACTER 10 
#define IDM_REGULAR   11 
#define IDM_BOLD      12 
#define IDM_ITALIC    13 
#define IDM_UNDERLINE 14 
 
// Structure associated with menu items 
 
typedef struct tagMYITEM 
{ 
    HFONT hfont; 
    int   cchItemText; 
    char  szItemText[1]; 
} MYITEM; 
 
#define CCH_MAXITEMTEXT 256 
 

The following are the relevant portions of the application's window procedure and its associated functions.

LRESULT CALLBACK MainWindowProc( 
        HWND hwnd, 
        UINT uMsg, 
        WPARAM wParam, 
        LPARAM lParam 
        ) 
{ 
    switch (uMsg) 
    { 
        case WM_CREATE: 
            if (!OnCreate(hwnd)) 
                return -1; 
            break; 
 
        case WM_DESTROY: 
            OnDestroy(hwnd); 
            PostQuitMessage(0); 
            break; 
 
        case WM_MEASUREITEM: 
            OnMeasureItem(hwnd, (LPMEASUREITEMSTRUCT) lParam); 
            return TRUE; 
 
        case WM_DRAWITEM: 
            OnDrawItem(hwnd, (LPDRAWITEMSTRUCT) lParam); 
            return TRUE; 
 
        // Additional message processing goes here. 
 
        default: 
            return DefWindowProc(hwnd, uMsg, wParam, lParam); 
    } 
    return 0; 
} 
 
 
BOOL WINAPI OnCreate(HWND hwnd) 
{ 
    HMENU hmenuBar = GetMenu(hwnd); 
    HMENU hmenuPopup; 
    MENUITEMINFO mii; 
    UINT uID; 
    MYITEM *pMyItem; 
 
    // Get a handle to the pop-up menu. 
 
    mii.fMask = MIIM_SUBMENU;     // information to get 
    GetMenuItemInfo(hmenuBar, IDM_CHARACTER, FALSE, &mii); 
    hmenuPopup = mii.hSubMenu; 
 
    // Modify each menu item. Assume that the IDs IDM_REGULAR 
    // through IDM_UNDERLINE are consecutive numbers. 
 
    for (uID = IDM_REGULAR; uID <= IDM_UNDERLINE; uID++) 
    { 
         // Allocate an item structure, leaving space for a 
         // string of up to CCH_MAXITEMTEXT characters. 
 
        pMyItem = (MYITEM *) LocalAlloc(LMEM_FIXED, 
                sizeof(MYITEM) + CCH_MAXITEMTEXT); 
 
        // Save the item text in the item structure. 
 
        mii.fMask = MIIM_STRING; 
        mii.dwTypeData = pMyItem->szItemText; 
        mii.cch = CCH_MAXITEMTEXT; 
        GetMenuItemInfo(hmenuPopup, uID, FALSE, &mii); 
        pMyItem->cchItemText = mii.cch; 
 
        // Reallocate the structure to the minimum required size. 
 
        pMyItem = (MYITEM *) LocalReAlloc(pMyItem, 
                sizeof(MYITEM) + mii.cch, LMEM_MOVEABLE); 
 
        // Create the font used to draw the item. 
 
        pMyItem->hfont = CreateMenuItemFont(uID); 
 
        // Change the item to an owner-drawn item, and save 
        // the address of the item structure as item data. 
 
        mii.fMask = MIIM_FTYPE | MIIM_DATA; 
        mii.fType = MFT_OWNERDRAW; 
        mii.dwItemData = (ULONG_PTR) pMyItem; 
        SetMenuItemInfo(hmenuPopup, uID, FALSE, &mii); 
    } 
    return TRUE; 
} 
 
HFONT CreateMenuItemFont(UINT uID) 
{ 
    LOGFONT lf;
    HRESULT hr; 
 
    ZeroMemory(&lf, sizeof(lf)); 
    lf.lfHeight = 20; 
    hr = StringCchCopy(lf.lfFaceName, 32, "Times New Roman");
    if (FAILED(hr))
    {
    // TODO: writer error handler
    } 
 
    switch (uID) 
    { 
        case IDM_BOLD: 
            lf.lfWeight = FW_HEAVY; 
            break; 
 
        case IDM_ITALIC: 
            lf.lfItalic = TRUE; 
            break; 
 
        case IDM_UNDERLINE: 
            lf.lfUnderline = TRUE; 
            break; 
    } 
    return CreateFontIndirect(&lf); 
} 
 
VOID WINAPI OnDestroy(HWND hwnd) 
{ 
    HMENU hmenuBar = GetMenu(hwnd); 
    HMENU hmenuPopup; 
    MENUITEMINFO mii; 
    UINT uID; 
    MYITEM *pMyItem; 
 
    // Get a handle to the menu. 
 
    mii.fMask = MIIM_SUBMENU;     // information to get  
    GetMenuItemInfo(hmenuBar, IDM_CHARACTER, FALSE, &mii); 
    hmenuPopup = mii.hSubMenu; 
 
    // Free resources associated with each menu item. 
 
    for (uID = IDM_REGULAR; uID <= IDM_UNDERLINE; uID++) 
    { 
        // Get the item data. 
 
        mii.fMask = MIIM_DATA; 
        GetMenuItemInfo(hmenuPopup, uID, FALSE, &mii); 
        pMyItem = (MYITEM *) mii.dwItemData; 
 
        // Destroy the font and free the item structure. 
 
        DeleteObject(pMyItem->hfont); 
        LocalFree(pMyItem); 
    } 
} 
 
VOID WINAPI OnMeasureItem(HWND hwnd, LPMEASUREITEMSTRUCT lpmis) 
{ 
    MYITEM *pMyItem = (MYITEM *) lpmis->itemData; 
    HDC hdc = GetDC(hwnd); 
    HFONT hfntOld = (HFONT)SelectObject(hdc, pMyItem->hfont); 
    SIZE size; 
 
    GetTextExtentPoint32(hdc, pMyItem->szItemText, 
            pMyItem->cchItemText, &size); 
 
    lpmis->itemWidth = size.cx; 
    lpmis->itemHeight = size.cy; 
 
    SelectObject(hdc, hfntOld); 
    ReleaseDC(hwnd, hdc); 
} 
 
VOID WINAPI OnDrawItem(HWND hwnd, LPDRAWITEMSTRUCT lpdis) 
{ 
    MYITEM *pMyItem = (MYITEM *) lpdis->itemData; 
    COLORREF clrPrevText, clrPrevBkgnd; 
    HFONT hfntPrev; 
    int x, y; 
 
    // Set the appropriate foreground and background colors. 
 
    if (lpdis->itemState & ODS_SELECTED) 
    { 
        clrPrevText = SetTextColor(lpdis->hDC, 
                GetSysColor(COLOR_HIGHLIGHTTEXT)); 
        clrPrevBkgnd = SetBkColor(lpdis->hDC, 
                GetSysColor(COLOR_HIGHLIGHT)); 
    } 
    else 
    { 
        clrPrevText = SetTextColor(lpdis->hDC, 
                GetSysColor(COLOR_MENUTEXT)); 
        clrPrevBkgnd = SetBkColor(lpdis->hDC, 
                GetSysColor(COLOR_MENU)); 
    } 
 
    // Determine where to draw and leave space for a check mark. 
 
    x = lpdis->rcItem.left; 
    y = lpdis->rcItem.top; 
    x += GetSystemMetrics(SM_CXMENUCHECK); 
 
    // Select the font and draw the text. 
 
    hfntPrev = (HFONT)SelectObject(lpdis->hDC, pMyItem->hfont); 
    ExtTextOut(lpdis->hDC, x, y, ETO_OPAQUE, 
            &lpdis->rcItem, pMyItem->szItemText, 
            pMyItem->cchItemText, NULL); 
 
    // Restore the original font and colors. 
 
    SelectObject(lpdis->hDC, hfntPrev); 
    SetTextColor(lpdis->hDC, clrPrevText); 
    SetBkColor(lpdis->hDC, clrPrevBkgnd); 
} 

Using Custom Check Mark Bitmaps

The system provides a default check-mark bitmap for displaying next to a menu item that is selected. You can customize an individual menu item by providing a pair of bitmaps to replace the default check-mark bitmap. The system displays one bitmap when the item is selected and the other when it is clear. This section describes the steps involved in creating and using custom check-mark bitmaps.

Creating Custom Check Mark Bitmaps

A custom check-mark bitmap must be the same size as the default check-mark bitmap. You can retrieve the default check-mark size of the bitmap by calling the GetSystemMetrics function. The low-order word of this function's return value specifies the width; the high-order word specifies the height.

You can use bitmap resources to provide check-mark bitmaps. However, because the required bitmap size varies depending on the display type, you may need to resize the bitmap at run time by using the StretchBlt function. Depending on the bitmap, the distortion caused by sizing could produce unacceptable results.

Instead of using a bitmap resource, you can create a bitmap at run time by using GDI functions.

To create a bitmap at run time

  1. Use the CreateCompatibleDC function to create a device context compatible with the one used by the application's main window.

    The function's hdc parameter can specify either NULL or the return value from the function. CreateCompatibleDC returns a handle to the compatible device context.

  2. Use the CreateCompatibleBitmap function to create a bitmap compatible with the application's main window.

    This function's nWidth and nHeight parameters set the size of the bitmap; they should specify the width and height information returned by the GetSystemMetrics function.

    Note

    You can also use the CreateBitmap function to create a monochrome bitmap.

     

  3. Use the SelectObject function to select the bitmap into the compatible device context.

  4. Use GDI drawing functions, such as Ellipse and LineTo, to draw an image into the bitmap, or use functions such as BitBlt and StretchBlt to copy an image into the bitmap.

For more information, see Bitmaps.

Associating Bitmaps with a Menu Item

You associate a pair of check-mark bitmaps with a menu item by passing the handles of the bitmaps to the SetMenuItemBitmaps function. The hBitmapUnchecked parameter identifies the clear bitmap, and the hBitmapChecked parameter identifies the selected bitmap. If you want to remove one or both check marks from a menu item, you can set the hBitmapUnchecked or hBitmapChecked parameter, or both, to NULL.

Setting the Check-mark Attribute

The CheckMenuItem function sets a menu item's check-mark attribute to either selected or cleared. You can specify the MF_CHECKED value to set the check-mark attribute to selected and the MF_UNCHECKED value to set it to clear.

You can also set the check state of a menu item by using the SetMenuItemInfo function.

Sometimes a group of menu items represents a set of mutually exclusive options. By using the CheckMenuRadioItem function, you can check one menu item while simultaneously removing the check mark from all other menu items in the group.

Simulating Check Boxes in a Menu

This topic contains an example that shows how to simulate check boxes in a menu. The example contains a Character menu whose items allow the user to set the bold, italic, and underline attributes of the current font. When a font attribute is in effect, a check mark is displayed in the check box next to the corresponding menu item; otherwise, an empty check box is displayed next to the item.

The example replaces the default check-mark bitmap with two bitmaps: a bitmap with a selected check box and the bitmap with an empty box. The selected check box bitmap is displayed next to the Bold, Italic, or Underline menu item when the item's check-mark attribute is set to MF_CHECKED. The clear or empty check box bitmap is displayed when the check-mark attribute is set to MF_UNCHECKED.

The system provides a predefined bitmap that contains the images used for check boxes and radio buttons. The example isolates the selected and empty check boxes, copies them to two separate bitmaps, and then uses them as the selected and cleared bitmaps for items in the Character menu.

To retrieve a handle to the system-defined check box bitmap, the example calls the LoadBitmap function, specifying NULL as the hInstance parameter and OBM_CHECKBOXES as the lpBitmapName parameter. Because the images in the bitmap are all the same size, the example can isolate them by dividing the bitmap width and height by the number of images in its rows and columns.

The following portion of a resource-definition file shows how the menu items in the Character menu are defined. Note that no font attributes are in effect initially, so the check-mark attribute for the Regular item is set to selected and, by default, the check-mark attribute of the remaining items is set to clear.

#include "men3.h" 
 
MainMenu MENU 
BEGIN 
    POPUP   "&Character" 
    BEGIN 
        MENUITEM    "&Regular",     IDM_REGULAR, CHECKED 
        MENUITEM SEPARATOR 
        MENUITEM    "&Bold",        IDM_BOLD 
        MENUITEM    "&Italic",      IDM_ITALIC 
        MENUITEM    "&Underline",   IDM_ULINE 
    END 
END

Here are the relevant contents of the application's header file.

// Menu-item identifiers  
 
#define IDM_REGULAR 0x1 
#define IDM_BOLD    0x2 
#define IDM_ITALIC  0x4 
#define IDM_ULINE   0x8 
 
// Check-mark flags  
 
#define CHECK   1 
#define UNCHECK 2 
 
// Font-attribute mask  
 
#define ATTRIBMASK 0xe 
 
// Function prototypes  
 
LRESULT APIENTRY MainWndProc(HWND, UINT, WPARAM, LPARAM); 
HBITMAP GetMyCheckBitmaps(UINT); 
BYTE CheckOrUncheckMenuItem(BYTE, HMENU); 

The following example shows the portions of the window procedure that create the check-mark bitmaps; set the check-mark attribute of the Bold, Italic, and Underline menu items; and destroy check-mark bitmaps.

LRESULT APIENTRY MainWndProc(HWND hwndMain, UINT uMsg, WPARAM wParam, LPARAM lParam) 
{ 
 
    static HBITMAP hbmpCheck;   // handle to checked bitmap    
    static HBITMAP hbmpUncheck; // handle to unchecked bitmap  
    static HMENU hmenu;         // handle to main menu         
    BYTE fbFontAttrib;          // font-attribute flags        
 
    switch (uMsg) 
    { 
        case WM_CREATE: 
 
            // Call the application-defined GetMyCheckBitmaps 
            // function to get the predefined checked and 
            // unchecked check box bitmaps. 
 
            hbmpCheck = GetMyCheckBitmaps(CHECK); 
            hbmpUncheck = GetMyCheckBitmaps(UNCHECK); 
 
            // Set the checked and unchecked bitmaps for the menu 
            // items. 
 
            hmenu = GetMenu(hwndMain); 
            SetMenuItemBitmaps(hmenu, IDM_BOLD, MF_BYCOMMAND, 
                hbmpUncheck, hbmpCheck); 
            SetMenuItemBitmaps(hmenu, IDM_ITALIC, MF_BYCOMMAND, 
                hbmpUncheck, hbmpCheck); 
            SetMenuItemBitmaps(hmenu, IDM_ULINE, MF_BYCOMMAND, 
                hbmpUncheck, hbmpCheck); 
 
            return 0; 
 
        case WM_COMMAND: 
            switch (LOWORD(wParam)) 
            { 
                // Process the menu commands.  
 
                case IDM_REGULAR: 
                case IDM_BOLD: 
                case IDM_ITALIC: 
                case IDM_ULINE: 
 
                    // CheckOrUncheckMenuItem is an application- 
                    // defined function that sets the menu item 
                    // checkmarks and returns the user-selected 
                    // font attributes. 
 
                    fbFontAttrib = CheckOrUncheckMenuItem( 
                        (BYTE) LOWORD(wParam), hmenu); 
 
                    // Set the font attributes.  
 
                    return 0; 
 
                // Process other command messages.  
 
                default: 
                    break; 
            } 
 
            break; 
 
        // Process other window messages.  
 
        case WM_DESTROY: 
 
            // Destroy the checked and unchecked bitmaps.  
 
            DeleteObject(hbmpCheck); 
            DeleteObject(hbmpUncheck); 
 
            PostQuitMessage(0); 
            break; 
 
        default: 
            return DefWindowProc(hwndMain, uMsg, wParam, lParam); 
    } 
    return NULL; 
} 
 
HBITMAP GetMyCheckBitmaps(UINT fuCheck) 
{ 
    COLORREF crBackground;  // background color                  
    HBRUSH hbrBackground;   // background brush                  
    HBRUSH hbrTargetOld;    // original background brush         
    HDC hdcSource;          // source device context             
    HDC hdcTarget;          // target device context             
    HBITMAP hbmpCheckboxes; // handle to check-box bitmap        
    BITMAP bmCheckbox;      // structure for bitmap data         
    HBITMAP hbmpSourceOld;  // handle to original source bitmap  
    HBITMAP hbmpTargetOld;  // handle to original target bitmap  
    HBITMAP hbmpCheck;      // handle to check-mark bitmap       
    RECT rc;                // rectangle for check-box bitmap    
    WORD wBitmapX;          // width of check-mark bitmap        
    WORD wBitmapY;          // height of check-mark bitmap       
 
    // Get the menu background color and create a solid brush 
    // with that color. 
 
    crBackground = GetSysColor(COLOR_MENU); 
    hbrBackground = CreateSolidBrush(crBackground); 
 
    // Create memory device contexts for the source and 
    // destination bitmaps. 
 
    hdcSource = CreateCompatibleDC((HDC) NULL); 
    hdcTarget = CreateCompatibleDC(hdcSource); 
 
    // Get the size of the system default check-mark bitmap and 
    // create a compatible bitmap of the same size. 
 
    wBitmapX = GetSystemMetrics(SM_CXMENUCHECK); 
    wBitmapY = GetSystemMetrics(SM_CYMENUCHECK); 
 
    hbmpCheck = CreateCompatibleBitmap(hdcSource, wBitmapX, 
        wBitmapY); 
 
    // Select the background brush and bitmap into the target DC. 
 
    hbrTargetOld = SelectObject(hdcTarget, hbrBackground); 
    hbmpTargetOld = SelectObject(hdcTarget, hbmpCheck); 
 
    // Use the selected brush to initialize the background color 
    // of the bitmap in the target device context. 
 
    PatBlt(hdcTarget, 0, 0, wBitmapX, wBitmapY, PATCOPY); 
 
    // Load the predefined check box bitmaps and select it 
    // into the source DC. 
 
    hbmpCheckboxes = LoadBitmap((HINSTANCE) NULL, 
        (LPTSTR) OBM_CHECKBOXES); 
 
    hbmpSourceOld = SelectObject(hdcSource, hbmpCheckboxes); 
 
    // Fill a BITMAP structure with information about the 
    // check box bitmaps, and then find the upper-left corner of 
    // the unchecked check box or the checked check box. 
 
    GetObject(hbmpCheckboxes, sizeof(BITMAP), &bmCheckbox); 
 
    if (fuCheck == UNCHECK) 
    { 
        rc.left = 0; 
        rc.right = (bmCheckbox.bmWidth / 4); 
    } 
    else 
    { 
        rc.left = (bmCheckbox.bmWidth / 4); 
        rc.right = (bmCheckbox.bmWidth / 4) * 2; 
    } 
 
    rc.top = 0; 
    rc.bottom = (bmCheckbox.bmHeight / 3); 
 
    // Copy the appropriate bitmap into the target DC. If the 
    // check-box bitmap is larger than the default check-mark 
    // bitmap, use StretchBlt to make it fit; otherwise, just 
    // copy it. 
 
    if (((rc.right - rc.left) > (int) wBitmapX) || 
            ((rc.bottom - rc.top) > (int) wBitmapY)) 
    {
        StretchBlt(hdcTarget, 0, 0, wBitmapX, wBitmapY, 
            hdcSource, rc.left, rc.top, rc.right - rc.left, 
            rc.bottom - rc.top, SRCCOPY); 
    }
 
    else 
    {
        BitBlt(hdcTarget, 0, 0, rc.right - rc.left, 
            rc.bottom - rc.top, 
            hdcSource, rc.left, rc.top, SRCCOPY); 
    }
 
    // Select the old source and destination bitmaps into the 
    // source and destination DCs, and then delete the DCs and 
    // the background brush. 
 
    SelectObject(hdcSource, hbmpSourceOld); 
    SelectObject(hdcTarget, hbrTargetOld); 
    hbmpCheck = SelectObject(hdcTarget, hbmpTargetOld); 
 
    DeleteObject(hbrBackground); 
    DeleteObject(hdcSource); 
    DeleteObject(hdcTarget); 
 
    // Return a handle to the new check-mark bitmap.  
 
    return hbmpCheck; 
} 
 
 
BYTE CheckOrUncheckMenuItem(BYTE bMenuItemID, HMENU hmenu) 
{ 
    DWORD fdwMenu; 
    static BYTE fbAttributes; 
 
    switch (bMenuItemID) 
    { 
        case IDM_REGULAR: 
 
            // Whenever the Regular menu item is selected, add a 
            // check mark to it and then remove checkmarks from 
            // any font-attribute menu items. 
 
            CheckMenuItem(hmenu, IDM_REGULAR, MF_BYCOMMAND | 
                MF_CHECKED); 
 
            if (fbAttributes & ATTRIBMASK) 
            { 
                CheckMenuItem(hmenu, IDM_BOLD, MF_BYCOMMAND | 
                    MF_UNCHECKED); 
                CheckMenuItem(hmenu, IDM_ITALIC, MF_BYCOMMAND | 
                    MF_UNCHECKED); 
                CheckMenuItem(hmenu, IDM_ULINE, MF_BYCOMMAND | 
                    MF_UNCHECKED); 
            } 
            fbAttributes = IDM_REGULAR; 
            return fbAttributes; 
 
        case IDM_BOLD: 
        case IDM_ITALIC: 
        case IDM_ULINE: 
 
            // Toggle the check mark for the selected menu item and 
            // set the font attribute flags appropriately. 
 
            fdwMenu = GetMenuState(hmenu, (UINT) bMenuItemID, 
                MF_BYCOMMAND); 
            if (!(fdwMenu & MF_CHECKED)) 
            { 
                CheckMenuItem(hmenu, (UINT) bMenuItemID, 
                    MF_BYCOMMAND | MF_CHECKED); 
                fbAttributes |= bMenuItemID; 
            }
            else 
            { 
                CheckMenuItem(hmenu, (UINT) bMenuItemID, 
                    MF_BYCOMMAND | MF_UNCHECKED); 
                fbAttributes ^= bMenuItemID; 
            } 
 
            // If any font attributes are currently selected, 
            // remove the check mark from the Regular menu item; 
            // if no attributes are selected, add a check mark 
            // to the Regular menu item. 
 
            if (fbAttributes & ATTRIBMASK) 
            { 
                CheckMenuItem(hmenu, IDM_REGULAR, 
                    MF_BYCOMMAND | MF_UNCHECKED); 
                fbAttributes &= (BYTE) ~IDM_REGULAR; 
            }
            else 
            { 
                CheckMenuItem(hmenu, IDM_REGULAR, 
                    MF_BYCOMMAND | MF_CHECKED); 
                fbAttributes = IDM_REGULAR; 
            } 
 
            return fbAttributes; 
    } 
} 

Example of Using Custom Check-mark Bitmaps

The example in this topic assigns custom check-mark bitmaps to menu items in two menus. The menu items in the first menu specify character attributes: bold, italic, and underline. Each menu item can be either selected or cleared. For these menu items, the example uses check-mark bitmaps that resemble the selected and cleared states of a check box control.

The menu items in the second menu specify paragraph alignment settings: left, centered, and right. Only one of these menu items is selected at any time. For these menu items, the example uses check-mark bitmaps that resemble the selected and clear states of a radio button control.

The window procedure processes the WM_CREATE message by calling the application-defined OnCreate function. OnCreate creates the four check-mark bitmaps and then assigns them to their appropriate menu items by using the SetMenuItemBitmaps function.

To create each bitmap, OnCreate calls the application-defined CreateMenuBitmaps function, specifying a pointer to a bitmap-specific drawing function. CreateMenuBitmaps creates a monochrome bitmap of the required size, selects it into a memory device context, and erases the background. Then it calls the specified drawing function to fill in the foreground.

The four application-defined drawing functions are DrawCheck, DrawUncheck, DrawRadioCheck, and DrawRadioUncheck. They draw a rectangle with an X, an empty rectangle, an ellipse containing a smaller filled ellipse, and an empty ellipse, respectively.

The window procedure processes the WM_DESTROY message by deleting the check-mark bitmaps. It retrieves each bitmap handle by using the GetMenuItemInfo function and then passes a handle to the function.

When the user chooses a menu item, a WM_COMMAND message is sent to the owner window. For menu items on the Character menu, the window procedure calls the application-defined CheckCharacterItem function. For items on the Paragraph menu, the window procedure calls the application-defined CheckParagraphItem function.

Each item on the Character menu can be selected and cleared independently. Therefore, CheckCharacterItem simply switches the specified menu item's check state. First, the function calls the GetMenuItemInfo function to get the current menu item state. Then it switches the MFS_CHECKED state flag and sets the new state by calling the SetMenuItemInfo function.

Unlike character attributes, only one paragraph alignment can be selected at a time. Therefore, CheckParagraphItem checks the specified menu item and removes the check mark from all other items on the menu. To do so, it calls the CheckMenuRadioItem function.

Following are the relevant portions of the application's header file.

// Menu-item identifiers for the Character menu 
 
#define IDM_CHARACTER 10 
#define IDM_BOLD      11 
#define IDM_ITALIC    12 
#define IDM_UNDERLINE 13 
 
// Menu-item identifiers for the Paragraph menu 
 
#define IDM_PARAGRAPH 20 
#define IDM_LEFT      21 
#define IDM_CENTER    22 
#define IDM_RIGHT     23 
 
// Function-pointer type for drawing functions 
 
typedef VOID (WINAPI * DRAWFUNC)(HDC hdc, SIZE size); 
 

The following are the relevant portions of the application's window procedure and related functions.

LRESULT CALLBACK MainWindowProc( 
        HWND hwnd, 
        UINT uMsg, 
        WPARAM wParam, 
        LPARAM lParam 
        ) 
{ 
    switch (uMsg) 
    { 
        case WM_CREATE: 
            if (!OnCreate(hwnd)) 
                return -1; 
            break; 
 
        case WM_DESTROY: 
            OnDestroy(hwnd); 
            PostQuitMessage(0); 
            break; 
 
        case WM_COMMAND: 
            switch (LOWORD(wParam)) 
            { 
                case IDM_BOLD: 
                case IDM_ITALIC: 
                case IDM_UNDERLINE: 
                    CheckCharacterItem(hwnd, LOWORD(wParam)); 
                    break; 
 
                case IDM_LEFT: 
                case IDM_CENTER: 
                case IDM_RIGHT: 
                    CheckParagraphItem(hwnd, LOWORD(wParam)); 
                    break; 
 
                // Process other commands here. 
 
            } 
            break; 
 
        // Process other messages here. 
 
        default: 
            return DefWindowProc(hwnd, uMsg, wParam, lParam); 
    } 
    return 0; 
} 
 
VOID WINAPI CheckCharacterItem(HWND hwnd, UINT uID) 
{ 
    HMENU hmenuBar = GetMenu(hwnd); 
    HMENU hmenuPopup; 
    MENUITEMINFO mii; 
 
    // Get a handle to the Character menu. 
 
    mii.fMask = MIIM_SUBMENU;  // information to get 
    GetMenuItemInfo(hmenuBar, IDM_CHARACTER, FALSE, &mii); 
    hmenuPopup = mii.hSubMenu; 
 
    // Get the state of the specified menu item. 
 
    mii.fMask = MIIM_STATE;    // information to get 
    GetMenuItemInfo(hmenuPopup, uID, FALSE, &mii); 
 
    // Toggle the checked state. 
 
    mii.fState ^= MFS_CHECKED; 
    SetMenuItemInfo(hmenuPopup, uID, FALSE, &mii); 
} 
 
VOID WINAPI CheckParagraphItem(HWND hwnd, UINT uID) 
{ 
    HMENU hmenuBar = GetMenu(hwnd); 
    HMENU hmenuPopup; 
    MENUITEMINFO mii; 
 
    // Get a handle to the Paragraph menu. 
 
    mii.fMask = MIIM_SUBMENU;  // information to get 
    GetMenuItemInfo(hmenuBar, IDM_PARAGRAPH, FALSE, &mii); 
    hmenuPopup = mii.hSubMenu; 
 
    // Check the specified item and uncheck all the others. 
 
    CheckMenuRadioItem( 
            hmenuPopup,         // handle to menu 
            IDM_LEFT,           // first item in range 
            IDM_RIGHT,          // last item in range 
            uID,                // item to check 
            MF_BYCOMMAND        // IDs, not positions 
            ); 
} 
 
BOOL WINAPI OnCreate(HWND hwnd) 
{ 
    HMENU hmenuBar = GetMenu(hwnd); 
    HMENU hmenuPopup; 
    MENUITEMINFO mii; 
    UINT uID; 
    HBITMAP hbmChecked; 
    HBITMAP hbmUnchecked; 
 
    // Get a handle to the Character menu. 
 
    mii.fMask = MIIM_SUBMENU;     // information to get 
    GetMenuItemInfo(hmenuBar, IDM_CHARACTER, FALSE, &mii); 
    hmenuPopup = mii.hSubMenu; 
 
    // Create the checked and unchecked bitmaps. 
 
    hbmChecked = CreateMenuBitmap(DrawCheck); 
    hbmUnchecked = CreateMenuBitmap(DrawUncheck); 
 
    // Set the check-mark bitmaps for each menu item. 
 
    for (uID = IDM_BOLD; uID <= IDM_UNDERLINE; uID++) 
    { 
        SetMenuItemBitmaps(hmenuPopup, uID, MF_BYCOMMAND, 
                hbmUnchecked, hbmChecked); 
    } 
 
    // Get a handle to the Paragraph pop-up menu. 
 
    mii.fMask = MIIM_SUBMENU;     // information to get 
    GetMenuItemInfo(hmenuBar, IDM_PARAGRAPH, FALSE, &mii); 
    hmenuPopup = mii.hSubMenu; 
 
    // Create the checked and unchecked bitmaps. 
 
    hbmChecked = CreateMenuBitmap(DrawRadioCheck); 
    hbmUnchecked = CreateMenuBitmap(DrawRadioUncheck); 
 
    // Set the check-mark bitmaps for each menu item. 
 
    for (uID = IDM_LEFT; uID <= IDM_RIGHT; uID++) 
    { 
        SetMenuItemBitmaps(hmenuPopup, uID, MF_BYCOMMAND, 
                hbmUnchecked, hbmChecked); 
    } 
 
    // Initially check the IDM_LEFT paragraph item. 
 
    CheckMenuRadioItem(hmenuPopup, IDM_LEFT, IDM_RIGHT, 
            IDM_LEFT, MF_BYCOMMAND); 
    return TRUE; 
} 
 
HBITMAP WINAPI CreateMenuBitmap(DRAWFUNC lpfnDraw) 
{ 
    // Create a DC compatible with the desktop window's DC. 
 
    HWND hwndDesktop = GetDesktopWindow(); 
    HDC hdcDesktop = GetDC(hwndDesktop); 
    HDC hdcMem = CreateCompatibleDC(hdcDesktop); 
 
    // Determine the required bitmap size. 
 
    SIZE size = { GetSystemMetrics(SM_CXMENUCHECK), 
                  GetSystemMetrics(SM_CYMENUCHECK) }; 
 
    // Create a monochrome bitmap and select it. 
 
    HBITMAP hbm = CreateBitmap(size.cx, size.cy, 1, 1, NULL); 
    HBITMAP hbmOld = SelectObject(hdcMem, hbm); 
 
    // Erase the background and call the drawing function. 
 
    PatBlt(hdcMem, 0, 0, size.cx, size.cy, WHITENESS); 
    (*lpfnDraw)(hdcMem, size); 
 
    // Clean up. 
 
    SelectObject(hdcMem, hbmOld); 
    DeleteDC(hdcMem); 
    ReleaseDC(hwndDesktop, hdcDesktop); 
    return hbm; 
} 
 
VOID WINAPI DrawCheck(HDC hdc, SIZE size) 
{ 
    HBRUSH hbrOld; 
    hbrOld = SelectObject(hdc, GetStockObject(NULL_BRUSH)); 
    Rectangle(hdc, 0, 0, size.cx, size.cy); 
    MoveToEx(hdc, 0, 0, NULL); 
    LineTo(hdc, size.cx, size.cy); 
    MoveToEx(hdc, 0, size.cy - 1, NULL); 
    LineTo(hdc, size.cx - 1, 0); 
    SelectObject(hdc, hbrOld); 
} 
 
VOID WINAPI DrawUncheck(HDC hdc, SIZE size) 
{ 
    HBRUSH hbrOld; 
    hbrOld = SelectObject(hdc, GetStockObject(NULL_BRUSH)); 
    Rectangle(hdc, 0, 0, size.cx, size.cy); 
    SelectObject(hdc, hbrOld); 
} 
 
VOID WINAPI DrawRadioCheck(HDC hdc, SIZE size) 
{ 
    HBRUSH hbrOld; 
    hbrOld = SelectObject(hdc, GetStockObject(NULL_BRUSH)); 
    Ellipse(hdc, 0, 0, size.cx, size.cy); 
    SelectObject(hdc, GetStockObject(BLACK_BRUSH)); 
    Ellipse(hdc, 2, 2, size.cx - 2, size.cy - 2); 
    SelectObject(hdc, hbrOld); 
} 
 
VOID WINAPI DrawRadioUncheck(HDC hdc, SIZE size) 
{ 
    HBRUSH hbrOld; 
    hbrOld = SelectObject(hdc, GetStockObject(NULL_BRUSH)); 
    Ellipse(hdc, 0, 0, size.cx, size.cy); 
    SelectObject(hdc, hbrOld); 
} 
 
VOID WINAPI OnDestroy(HWND hwnd) 
{ 
    HMENU hmenuBar = GetMenu(hwnd); 
    HMENU hmenuPopup; 
    MENUITEMINFO mii; 
 
    // Get a handle to the Character menu. 
 
    mii.fMask = MIIM_SUBMENU;     // information to get 
    GetMenuItemInfo(hmenuBar, IDM_CHARACTER, FALSE, &mii); 
    hmenuPopup = mii.hSubMenu; 
 
    // Get the check-mark bitmaps and delete them. 
 
    mii.fMask = MIIM_CHECKMARKS; 
    GetMenuItemInfo(hmenuPopup, IDM_BOLD, FALSE, &mii); 
    DeleteObject(mii.hbmpChecked); 
    DeleteObject(mii.hbmpUnchecked); 
 
    // Get a handle to the Paragraph menu. 
 
    mii.fMask = MIIM_SUBMENU;     // information to get 
    GetMenuItemInfo(hmenuBar, IDM_PARAGRAPH, FALSE, &mii); 
    hmenuPopup = mii.hSubMenu; 
 
    // Get the check-mark bitmaps and delete them. 
 
    mii.fMask = MIIM_CHECKMARKS; 
    GetMenuItemInfo(hmenuPopup, IDM_LEFT, FALSE, &mii); 
    DeleteObject(mii.hbmpChecked); 
    DeleteObject(mii.hbmpUnchecked); 
}