运行演示文档的问题
Posted
技术标签:
【中文标题】运行演示文档的问题【英文标题】：Issues with running a Demo Documentation 【发布时间】：2020-03-30 09:37:01 【问题描述】：我对 c++ 非常陌生，我正在查看有关如何使用 Win32 GUI 的示例
https://docs.microsoft.com/en-us/windows/win32/controls/create-an-owner-drawn-combo-box#instructions
我复制并粘贴了完整的代码，如图所示（在底部），但它给我带来了大量错误（主要是未声明的标识符）
#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'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));
谁能与我分享我错过了什么？或者我想如何正确运行它来查看输出 UI
【问题讨论】：
【参考方案1】：您需要在文件顶部添加#include windows.h> 才能使用 Win32 API。
【讨论】：
是的，我添加了#include如果您正在查看 MSDN，您需要了解您需要哪些包含和库。在您的页面上它不存在，但对于 Windows 程序，您需要 #include <Windows.h>。如果您遇到诸如 LNK2011 或 LNK2019 之类的错误，则说明链接存在问题。你用的是什么编辑器？要了解 Win32 API，请勿复制和粘贴。
【讨论】：
我使用的是 Visual Studio，代码中声明的 ID 变量很多以上是关于运行演示文档的问题的主要内容，如果未能解决你的问题，请参考以下文章
OpenOffice API：将 Impress（演示）文档保存为独立文件
ppt打不开，显示发现文件中的内容有问题。可尝试修复此演示文稿