如何建立擁有者繪製下拉式方塊

發行項
02/23/2024

本主題示範如何使用擁有者繪製的下拉式方塊。 C++ 程式代碼範例會使用擁有者繪製的下拉式清單框來顯示四個食物群組，每個群組都是以點陣圖和名稱表示。選取食物群組會導致該群組中的食物出現在清單中。

screen shot showing a dialog box with a list box and an expanded drop-down list box showing an icon and label for each item

對話框也包含清單框（IDLIST）和兩個按鈕： [確定 ] （IDOK）和 [取消 ] （IDCANCEL）。 IDOK 和 IDCANCEL 常數是由 SDK 頭檔所定義。常數IDLIST定義於應用程式的頭檔中，就像控制標識碼 IDCOMBO 一樣。如需對話框的詳細資訊，請參閱對話方塊。

您需要知道的事項

技術

Windows 控件

必要條件

C/C++
Windows 使用者介面程序設計

指示

步驟 1：建立擁有者繪製對話方塊

程式代碼範例會 使用 DialogBox 函式來建立強制響應對話方塊。對話框範本IDD_SQMEAL會定義下拉式方塊的視窗樣式、按鈕和控件識別碼。此範例中的下拉式方塊使用CBS_DROPDOWNLIST、CBS_OWNERDRAWFIXED、CBS_SORT、CBS_HASSTRINGS、WS_VSCROLL和WS_TABSTOP樣式。

DialogBox(hInst, MAKEINTRESOURCE(IDD_SQMEAL), 
    hWnd, FoodDlgProc);

步驟 2：處理對話框中的WM_INITDIALOG和WM_DESTROY訊息。

當您在對話框中使用下拉式方塊時，通常會藉由初始化下拉式方塊來回應 WM_INITDIALOG 訊息。應用程式會載入用於擁有者繪製下拉式方塊的點陣圖，然後呼叫應用程式定義的 InitGroupList 函式來初始化下拉式方塊。它也會選取下拉式方塊中的第一個清單專案，然後呼叫應用程式定義的 InitFoodList 函式來初始化清單框。

在此範例中，擁有者繪製的下拉式方塊是一個下拉式清單框，其中包含四個食品組的名稱。 InitGroupList 會新增每個食物群組的名稱，並使用 CB_SETITEMDATA 訊息，將位圖句柄與識別食物群組的每個清單專案產生關聯。

範例中的清單框包含所選食品群組中食物的名稱。 InitFoodList 會重設清單框的內容，然後在目前食品群組下拉式清單框中新增目前食物選取項目的名稱。

case WM_INITDIALOG:

    // Call an application-defined function to load bitmap resources.
    if (!LoadIconBitmaps())
    {
        EndDialog(hDlg, -1);
        break;
    }

    // Initialize the food groups combo box and select the first item.
    InitGroupList(hDlg);
    SendDlgItemMessage(hDlg, IDCOMBO, CB_SETCURSEL, 0, 0); 

    // Initialize the food list box and select the first item.
    InitFoodList(hDlg);
    SendDlgItemMessage(hDlg, IDLIST, LB_SETCURSEL, 0, 0); 

     return (INT_PTR)TRUE;

當它收到 WM_DESTROY 訊息時，應用程式會刪除擁有者繪製下拉式方塊中的位圖。

case WM_DESTROY:

    // Call the application-defined function to free the bitmap resources.
    DeleteIconBitmaps();
    break;

步驟 3：處理WM_MEASUREITEM訊息。

擁有者繪製的下拉式方塊會將 WM_MEASUREITEM 訊息傳送至其父視窗或對話框程式，讓應用程式可以設定每個清單項目的維度。由於範例下拉式方塊具有 CBS_OWNERDRAWFIXED 樣式，因此系統只會傳送 WM_MEASUREITEM 訊息一次。具有 CBS_OWNERDRAWVARIABLE 樣式的下拉式方塊會傳送 每個清單專案的WM_MEASUREITEM 訊息。

lParam 參數是 MEASUREITEMSTRUCT 結構的指標，可識別控件和列表專案。它也包含清單項目的預設維度。此範例會 修改 itemHeight 結構成員，以確保清單專案夠高，足以容納 food-group 位圖。

case WM_MEASUREITEM:
    {
    // Set the height of the items in the food groups combo box.
    LPMEASUREITEMSTRUCT lpmis = (LPMEASUREITEMSTRUCT) lParam;

    if (lpmis->itemHeight < CY_BITMAP + 2)
        lpmis->itemHeight = CY_BITMAP + 2;

    break;
    }

步驟 4：處理WM_DRAWITEM訊息。

每次應用程式必須重新繪製清單專案時，擁有者繪製下拉式方塊會將 WM_DRAWITEM 訊息傳送至其父視窗或對話框程式。 lParam 參數是 DRAWITEMSTRUCT 結構的指標，可識別控件和列表專案。它也包含繪製專案所需的資訊。

範例應用程式會顯示與食物群組相關聯的清單專案文字和點陣圖。如果專案有焦點，它也會繪製焦點矩形。在顯示文字之前，此範例會根據選取的項目來設定前景和背景色彩。因為下拉式方塊具有CBS_HASSTRINGS樣式，因此下拉式方塊會維護可使用CB_GETLBTEXT訊息擷取之每個清單專案的文字。

用於清單專案的點陣圖取決於食物群組。 InitGroupList 會 使用CB_SETITEMDATA 訊息，將點陣圖句柄與每個清單專案產生關聯。視窗程式會從 DRAWITEMSTRUCT 結構的 itemData 成員擷取位圖句柄。系統會針對每個食物群組符號使用兩個點陣圖：具有SRCAND點陣作業的單色位圖，以清除影像後面的不規則區域，並使用SRCPAINT點陣作業來繪製影像的色彩位圖。

case WM_DRAWITEM:
    {
    COLORREF clrBackground;
    COLORREF clrForeground;
    TEXTMETRIC tm;
    int x;
    int y;
    HRESULT hr;
    size_t cch;

    LPDRAWITEMSTRUCT lpdis = (LPDRAWITEMSTRUCT) lParam;
       
    if (lpdis->itemID == -1) // Empty item)
        break;

    // Get the food icon from the item data.
    hbmIcon = (HBITMAP) lpdis->itemData;

    // The colors depend on whether the item is selected.
    clrForeground = SetTextColor(lpdis->hDC, 
        GetSysColor(lpdis->itemState & ODS_SELECTED ?
        COLOR_HIGHLIGHTTEXT : COLOR_WINDOWTEXT));

    clrBackground = SetBkColor(lpdis->hDC, 
        GetSysColor(lpdis->itemState & ODS_SELECTED ?
        COLOR_HIGHLIGHT : COLOR_WINDOW));

    // Calculate the vertical and horizontal position.
    GetTextMetrics(lpdis->hDC, &tm);
    y = (lpdis->rcItem.bottom + lpdis->rcItem.top - tm.tmHeight) / 2;
    x = LOWORD(GetDialogBaseUnits()) / 4;

    // Get and display the text for the list item.
    SendMessage(lpdis->hwndItem, CB_GETLBTEXT,
        lpdis->itemID, (LPARAM) achTemp);

    hr = StringCchLength(achTemp, 256, &cch);
    if (FAILED(hr))
    {
        // TODO: Write error handler.
    }

    ExtTextOut(lpdis->hDC, CX_BITMAP + 2 * x, y,
        ETO_CLIPPED | ETO_OPAQUE, &lpdis->rcItem,
        achTemp, (UINT)cch, NULL);

    // Restore the previous colors.
    SetTextColor(lpdis->hDC, clrForeground);
    SetBkColor(lpdis->hDC, clrBackground);
    
    //  Draw the food icon for the item. 
    HDC hdc = CreateCompatibleDC(lpdis->hDC); 
    if (hdc == NULL) 
        break; 
 
    SelectObject(hdc, hbmMask); 
    BitBlt(lpdis->hDC, x, lpdis->rcItem.top + 1, 
        CX_BITMAP, CY_BITMAP, hdc, 0, 0, SRCAND); 
 
    SelectObject(hdc, hbmIcon); 
    BitBlt(lpdis->hDC, x, lpdis->rcItem.top + 1, 
        CX_BITMAP, CY_BITMAP, hdc, 0, 0, SRCPAINT); 
 
    DeleteDC(hdc); 
  
    // If the item has the focus, draw the focus rectangle.
    if (lpdis->itemState & ODS_FOCUS)
        DrawFocusRect(lpdis->hDC, &lpdis->rcItem);

    break;
    }

步驟 5：處理WM_COMMAND訊息。

當對話框控制件中發生事件時，控制項會透過WM_COMMAND訊息通知對話框程式。此範例會處理下拉式方塊、清單框和 [確定] 按鈕的通知訊息。控件標識碼是 wParam 的低序字，而通知程式代碼則位於 wParam 的高序字。

如果控件標識碼是 IDCOMBO，則下拉式方塊中已發生事件。回應中，對話框程式會忽略除了CBN_SELENDOK以外的所有其他下拉式方塊事件，這表示已進行選取、關閉下拉式清單框，而且應該接受所做的變更。對話框過程會呼叫 InitFoodList 來重設清單框的內容，並在下拉式清單框中新增目前選取項目的名稱。

如果控件識別碼是IDLIST，清單框中已發生事件。這會導致對話框程式忽略除了LBN_DBLCLK以外的所有清單框事件，這表示使用者已按兩下清單專案。此事件的處理方式與 已選擇 [確定] 按鈕的方式相同。

如果控件識別碼為 IDOK，則使用者已選擇 [ 確定 ] 按鈕。為了回應，對話框程式會將選取食品的名稱插入應用程式的多行編輯控件中，然後呼叫 EndDialog 函式來關閉對話方塊。

如果控制標識碼為 IDCANCEL，使用者已按兩下 [ 取消 ] 按鈕。為了回應，對話框程式會呼叫 EndDialog 來關閉對話框。

case WM_COMMAND:
        switch (LOWORD(wParam)) 
        { 
            case IDCOMBO: 
                if (HIWORD(wParam) == CBN_SELENDOK) 
                { 
                    InitFoodList(hDlg); 
                    SendDlgItemMessage(hDlg, IDLIST, 
                        LB_SETCURSEL, 0, 0); 
                } 
                break; 
 
            case IDLIST: 
                if (HIWORD(wParam) != LBN_DBLCLK) 
                    break; 
 
            // For a double-click, process the OK case. 
            case IDOK: 
 
                // Get the text for the selected list item. 
                hwnd = GetDlgItem(hDlg, IDLIST); 

                // Here it is assumed the text can fit into achTemp.
                // If there is doubt, call LB_GETTEXTLENGTH first.
                SendMessage(hwnd, LB_GETTEXT, 
                    SendMessage(hwnd, LB_GETCURSEL, 0, 0), 
                    (LPARAM) achTemp); 
 
                // TODO: Do something with the selected text.
 
                EndDialog(hDlg, 0); 
                break; 
 
            case IDCANCEL: 
                hwnd = GetDlgItem(hDlg, IDCOMBO); 
                if (SendMessage(hwnd, CB_GETDROPPEDSTATE, 0, 0)) 
                    SendMessage(hwnd, CB_SHOWDROPDOWN, FALSE, 0); 
                else EndDialog(hDlg, 0); 
        } 
        break;

完整範例

以下是 [方餐] 對話框的對話框程式和支援函式。

#define ID_BREAD 0
#define ID_DAIRY 1
#define ID_FRUIT 2
#define ID_MEAT  3

#define CX_BITMAP 24
#define CY_BITMAP 24

HBITMAP hbmBread;
HBITMAP hbmDairy;
HBITMAP hbmMeat;
HBITMAP hbmFruit;
HBITMAP hbmMask;

HBITMAP hbmIcon;

// Message handler for Square Meal dialog box.
INT_PTR CALLBACK FoodDlgProc(HWND hDlg, UINT message, WPARAM wParam, 
    LPARAM lParam)
{
    UNREFERENCED_PARAMETER(lParam);
    TCHAR achTemp[256];
    HWND hwnd;

    switch (message)
    {
    case WM_INITDIALOG:

        // Call an application-defined function to load bitmap resources.
        if (!LoadIconBitmaps())
        {
            EndDialog(hDlg, -1);
            break;
        }

        // Initialize the food groups combo box and select the first item.
        InitGroupList(hDlg);
        SendDlgItemMessage(hDlg, IDCOMBO, CB_SETCURSEL, 0, 0); 

        // Initialize the food list box and select the first item.
        InitFoodList(hDlg);
        SendDlgItemMessage(hDlg, IDLIST, LB_SETCURSEL, 0, 0); 

         return (INT_PTR)TRUE;
   
    case WM_MEASUREITEM:
        {
        // Set the height of the items in the food groups combo box.
        LPMEASUREITEMSTRUCT lpmis = (LPMEASUREITEMSTRUCT) lParam;

        if (lpmis->itemHeight < CY_BITMAP + 2)
            lpmis->itemHeight = CY_BITMAP + 2;

        break;
        }

    case WM_DRAWITEM:
        {
        COLORREF clrBackground;
        COLORREF clrForeground;
        TEXTMETRIC tm;
        int x;
        int y;
        HRESULT hr;
        size_t cch;

        LPDRAWITEMSTRUCT lpdis = (LPDRAWITEMSTRUCT) lParam;
           
        if (lpdis->itemID == -1) // Empty item)
            break;

        // Get the food icon from the item data.
        hbmIcon = (HBITMAP) lpdis->itemData;

        // The colors depend on whether the item is selected.
        clrForeground = SetTextColor(lpdis->hDC, 
            GetSysColor(lpdis->itemState & ODS_SELECTED ?
            COLOR_HIGHLIGHTTEXT : COLOR_WINDOWTEXT));

        clrBackground = SetBkColor(lpdis->hDC, 
            GetSysColor(lpdis->itemState & ODS_SELECTED ?
            COLOR_HIGHLIGHT : COLOR_WINDOW));

        // Calculate the vertical and horizontal position.
        GetTextMetrics(lpdis->hDC, &tm);
        y = (lpdis->rcItem.bottom + lpdis->rcItem.top - tm.tmHeight) / 2;
        x = LOWORD(GetDialogBaseUnits()) / 4;

        // Get and display the text for the list item.
        SendMessage(lpdis->hwndItem, CB_GETLBTEXT,
            lpdis->itemID, (LPARAM) achTemp);

        hr = StringCchLength(achTemp, 256, &cch);
        if (FAILED(hr))
        {
            // TODO: Write error handler.
        }

        ExtTextOut(lpdis->hDC, CX_BITMAP + 2 * x, y,
            ETO_CLIPPED | ETO_OPAQUE, &lpdis->rcItem,
            achTemp, (UINT)cch, NULL);

        // Restore the previous colors.
        SetTextColor(lpdis->hDC, clrForeground);
        SetBkColor(lpdis->hDC, clrBackground);
        
        //  Draw the food icon for the item. 
        HDC hdc = CreateCompatibleDC(lpdis->hDC); 
        if (hdc == NULL) 
            break; 
 
        SelectObject(hdc, hbmMask); 
        BitBlt(lpdis->hDC, x, lpdis->rcItem.top + 1, 
            CX_BITMAP, CY_BITMAP, hdc, 0, 0, SRCAND); 
 
        SelectObject(hdc, hbmIcon); 
        BitBlt(lpdis->hDC, x, lpdis->rcItem.top + 1, 
            CX_BITMAP, CY_BITMAP, hdc, 0, 0, SRCPAINT); 
 
        DeleteDC(hdc); 
      
        // If the item has the focus, draw the focus rectangle.
        if (lpdis->itemState & ODS_FOCUS)
            DrawFocusRect(lpdis->hDC, &lpdis->rcItem);

        break;
        }

    case WM_COMMAND:
            switch (LOWORD(wParam)) 
            { 
                case IDCOMBO: 
                    if (HIWORD(wParam) == CBN_SELENDOK) 
                    { 
                        InitFoodList(hDlg); 
                        SendDlgItemMessage(hDlg, IDLIST, 
                            LB_SETCURSEL, 0, 0); 
                    } 
                    break; 
 
                case IDLIST: 
                    if (HIWORD(wParam) != LBN_DBLCLK) 
                        break; 
 
                // For a double-click, process the OK case. 
                case IDOK: 
 
                    // Get the text for the selected list item. 
                    hwnd = GetDlgItem(hDlg, IDLIST); 

                    // Here it is assumed the text can fit into achTemp.
                    // If there is doubt, call LB_GETTEXTLENGTH first.
                    SendMessage(hwnd, LB_GETTEXT, 
                        SendMessage(hwnd, LB_GETCURSEL, 0, 0), 
                        (LPARAM) achTemp); 
 
                    // TODO: Do something with the selected text.
 
                    EndDialog(hDlg, 0); 
                    break; 
 
                case IDCANCEL: 
                    hwnd = GetDlgItem(hDlg, IDCOMBO); 
                    if (SendMessage(hwnd, CB_GETDROPPEDSTATE, 0, 0)) 
                        SendMessage(hwnd, CB_SHOWDROPDOWN, FALSE, 0); 
                    else EndDialog(hDlg, 0); 
            } 
            break; 

    case WM_DESTROY:

        // Call the application-defined function to free the bitmap resources.
        DeleteIconBitmaps();
        break;
    }
    return (INT_PTR)FALSE;
}

// Loads string resources and adds them as items to the drop-down list of
//   the food groups combo box. The bitmap handle of each item&#39;s icon is
//   stored as item data for easy access when the item needs to be drawn.
// 
void InitGroupList(HWND hDlg)
{
    TCHAR achTemp[256];
    DWORD dwIndex;

    // Get the handle of the food groups combo box.
    HWND hwndGroupsBox = GetDlgItem(hDlg, IDCOMBO);

    LoadString(hInst, IDS_BREAD, achTemp, sizeof(achTemp)/sizeof(TCHAR));
    dwIndex = SendMessage(hwndGroupsBox, CB_ADDSTRING, 0, (LPARAM) achTemp);
    SendMessage(hwndGroupsBox, CB_SETITEMDATA, dwIndex, (LPARAM) hbmBread);
    
    LoadString(hInst, IDS_DAIRY, achTemp, sizeof(achTemp)/sizeof(TCHAR)); 
    dwIndex = SendMessage(hwndGroupsBox, CB_ADDSTRING, 0, (LPARAM) achTemp);
    SendMessage(hwndGroupsBox, CB_SETITEMDATA, dwIndex, (LPARAM) hbmDairy);

    LoadString(hInst, IDS_FRUIT, achTemp, sizeof(achTemp)/sizeof(TCHAR));
    dwIndex = SendMessage(hwndGroupsBox, CB_ADDSTRING, 0, (LPARAM) achTemp);
    SendMessage(hwndGroupsBox, CB_SETITEMDATA, dwIndex, (LPARAM) hbmFruit); 

    LoadString(hInst, IDS_MEAT, achTemp, sizeof(achTemp)/sizeof(TCHAR)); 
    dwIndex = SendMessage(hwndGroupsBox, CB_ADDSTRING, 0, (LPARAM) achTemp);
    SendMessage(hwndGroupsBox, CB_SETITEMDATA, dwIndex, (LPARAM) hbmMeat);

    return;
}

// Fills the food list based on the selected item in the food groups
//   combo box.
void InitFoodList(HWND hDlg)
{
    TCHAR achTemp[256];

    HWND hwndGroupsBox = GetDlgItem(hDlg, IDCOMBO);
    HWND hwndFoodList = GetDlgItem(hDlg, IDLIST);

    // Clear the list contents.
    SendMessage(hwndFoodList, LB_RESETCONTENT, 0, 0);

    // Find out which food group is selected.
    int idFoodGroup = SendMessage(hwndGroupsBox, CB_GETCURSEL, 0, 0);

    switch (idFoodGroup)
    {
    case ID_BREAD:
        LoadString(hInst, IDS_OAT, achTemp, sizeof(achTemp)/sizeof(TCHAR));
        SendMessage(hwndFoodList, LB_ADDSTRING, 0, (LPARAM) achTemp);

        LoadString(hInst, IDS_WHEAT, achTemp, sizeof(achTemp)/sizeof(TCHAR));
        SendMessage(hwndFoodList, LB_ADDSTRING, 0, (LPARAM) achTemp);

        LoadString(hInst, IDS_RYE, achTemp, sizeof(achTemp)/sizeof(TCHAR));
        SendMessage(hwndFoodList, LB_ADDSTRING, 0, (LPARAM) achTemp);
        break;

    case ID_DAIRY:
        LoadString(hInst, IDS_CHEDDAR, achTemp, sizeof(achTemp)/sizeof(TCHAR));
        SendMessage(hwndFoodList, LB_ADDSTRING, 0, (LPARAM) achTemp);

        LoadString(hInst, IDS_MILK, achTemp, sizeof(achTemp)/sizeof(TCHAR));
        SendMessage(hwndFoodList, LB_ADDSTRING, 0, (LPARAM) achTemp);

        LoadString(hInst, IDS_PROCESSED, achTemp, sizeof(achTemp)/sizeof(TCHAR));
        SendMessage(hwndFoodList, LB_ADDSTRING, 0, (LPARAM) achTemp);

        LoadString(hInst, IDS_SWISS, achTemp, sizeof(achTemp)/sizeof(TCHAR));
        SendMessage(hwndFoodList, LB_ADDSTRING, 0, (LPARAM) achTemp);
        
        break;

    case ID_FRUIT:
        LoadString(hInst, IDS_APPLES, achTemp, sizeof(achTemp)/sizeof(TCHAR));
        SendMessage(hwndFoodList, LB_ADDSTRING, 0, (LPARAM) achTemp);

        LoadString(hInst, IDS_BANANAS, achTemp, sizeof(achTemp)/sizeof(TCHAR));
        SendMessage(hwndFoodList, LB_ADDSTRING, 0, (LPARAM) achTemp);

        LoadString(hInst, IDS_ORANGES, achTemp, sizeof(achTemp)/sizeof(TCHAR));
        SendMessage(hwndFoodList, LB_ADDSTRING, 0, (LPARAM) achTemp);

        break;

    case ID_MEAT:
        LoadString(hInst, IDS_BEEF, achTemp, sizeof(achTemp)/sizeof(TCHAR));
        SendMessage(hwndFoodList, LB_ADDSTRING, 0, (LPARAM) achTemp);

        LoadString(hInst, IDS_CHICKEN, achTemp, sizeof(achTemp)/sizeof(TCHAR));
        SendMessage(hwndFoodList, LB_ADDSTRING, 0, (LPARAM) achTemp);

        LoadString(hInst, IDS_PORK, achTemp, sizeof(achTemp)/sizeof(TCHAR));
        SendMessage(hwndFoodList, LB_ADDSTRING, 0, (LPARAM) achTemp);

        break;

    default:
        break;
    }

    return;
}

// Loads the food icon bitmaps from the application resources.
//
BOOL LoadIconBitmaps(void)
{
    hbmBread = LoadBitmap(hInst, MAKEINTRESOURCE(IDB_BREAD));

    if (hbmBread != NULL)
         hbmDairy = LoadBitmap(hInst, MAKEINTRESOURCE(IDB_DAIRY));

    if (hbmDairy != NULL)
         hbmMeat = LoadBitmap(hInst, MAKEINTRESOURCE(IDB_MEAT));

    if (hbmMeat != NULL)
        hbmFruit = LoadBitmap(hInst, MAKEINTRESOURCE(IDB_FRUIT));
    
    if (hbmFruit != NULL)
        hbmMask = LoadBitmap(hInst, MAKEINTRESOURCE(IDB_MASK));

    if (hbmMask != NULL)
        return TRUE;
        
    return FALSE;
}

// Frees the icon bitmps.
//
void DeleteIconBitmaps(void)
{
    FreeResource(reinterpret_cast<HGLOBAL>(hbmBread));
    FreeResource(reinterpret_cast<HGLOBAL>(hbmDairy));
    FreeResource(reinterpret_cast<HGLOBAL>(hbmMeat));
    FreeResource(reinterpret_cast<HGLOBAL>(hbmFruit));
    FreeResource(reinterpret_cast<HGLOBAL>(hbmMask));
}

使用下拉式方塊

共用方式為

如何建立擁有者繪製下拉式方塊

您需要知道的事項

技術

必要條件

指示

步驟 1：建立擁有者繪製對話方塊

步驟 2：處理對話框中的WM_INITDIALOG和WM_DESTROY訊息。

步驟 3：處理WM_MEASUREITEM訊息。

步驟 4：處理WM_DRAWITEM訊息。

步驟 5：處理WM_COMMAND訊息。

完整範例

意見反應

其他資源

共用方式為

如何建立擁有者繪製下拉式方塊

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技術

必要條件

指示

步驟 1：建立擁有者繪製對話方塊

步驟 2：處理對話框中的WM_INITDIALOG和WM_DESTROY訊息。

步驟 3：處理WM_MEASUREITEM訊息。

步驟 4：處理WM_DRAWITEM訊息。

步驟 5：處理WM_COMMAND訊息。

完整範例

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