原文： http://zetcode.com/gui/winapi/customcontrols/

在这里，我们将演示如何创建自己的自定义控件。 Windows API 具有各种预先构建的控件的集合。 必须手动创建更多特定的控件。 我们使用 GDI 创建自定义控件。

刻录控件

可以在各种媒体刻录应用中找到此控件，例如 Nero 刻录 ROM。

  1. #include <windows.h>
  2. #include <commctrl.h>
  3. #include <wchar.h>
  5. LRESULT CALLBACK PanelProc(HWND, UINT, WPARAM, LPARAM);
  6. LRESULT CALLBACK WndProc(HWND, UINT, WPARAM, LPARAM);
  8. HINSTANCE g_hinst;
  9. LRESULT g_pos = 150;
  11. int WINAPI wWinMain(HINSTANCE hInstance, HINSTANCE hPrevInstance, 
  12.                     PWSTR lpCmdLine, int nCmdShow)
  13. {
  14.   HWND hwnd;
  15.   MSG  msg;    
  16.   WNDCLASSW wc = {0};
  18.   wc.lpszClassName = L"Application";
  19.   wc.hInstance     = hInstance;
  20.   wc.hbrBackground = GetSysColorBrush(COLOR_3DFACE);
  21.   wc.lpfnWndProc   = WndProc;
  22.   wc.hCursor       = LoadCursor(0, IDC_ARROW);
  24.   g_hinst = hInstance;
  26.   RegisterClassW(&wc);
  27.   hwnd = CreateWindowW(wc.lpszClassName, L"Burning control",
  28.                 WS_OVERLAPPEDWINDOW | WS_VISIBLE | WS_CLIPCHILDREN,
  29.                 100, 100, 400, 250, 0, 0, hInstance, 0);  
  31.   while( GetMessage(&msg, NULL, 0, 0)) {
  32.     DispatchMessage(&msg);
  33.   }
  35.   return (int) msg.wParam;
  36. }
  38. LRESULT CALLBACK WndProc(HWND hwnd, UINT msg, 
  39.     WPARAM wParam, LPARAM lParam)
  40. {
  42.   static HWND hwndTrack, hwndBurn;
  43.   WNDCLASSW rwc = {0};
  45.   INITCOMMONCONTROLSEX InitCtrlEx;
  47.   InitCtrlEx.dwSize = sizeof(INITCOMMONCONTROLSEX);
  48.   InitCtrlEx.dwICC  = ICC_BAR_CLASSES;
  49.   InitCommonControlsEx(&InitCtrlEx);
  51.   switch(msg)  
  52.   {
  53.       case WM_CREATE:
  55.           rwc.lpszClassName = L"BurningControl";
  57.           rwc.hbrBackground = GetSysColorBrush(COLOR_BTNFACE);
  58.           rwc.style         = CS_HREDRAW;
  59.           rwc.lpfnWndProc   = PanelProc;
  60.           rwc.hCursor       = LoadCursor(0, IDC_ARROW);
  61.           RegisterClassW(&rwc);
  63.           hwndBurn = CreateWindowExW(WS_EX_STATICEDGE , L"BurningControl", NULL,
  64.               WS_CHILD | WS_VISIBLE, 0, 330, 490, 30, hwnd, (HMENU)1, NULL, NULL);
  66.           hwndTrack = CreateWindowExW(0, TRACKBAR_CLASSW, NULL,
  67.               WS_CHILD | WS_VISIBLE | TBS_FIXEDLENGTH | TBS_NOTICKS,
  68.               40, 25, 150, 25, hwnd, (HMENU) 2, g_hinst, NULL);
  70.           SendMessage(hwndTrack, TBM_SETRANGE,  TRUE,  MAKELONG(0, 750));
  71.           SendMessage(hwndTrack, TBM_SETPAGESIZE, 0,  20); 
  72.           SendMessage(hwndTrack, TBM_SETTICFREQ, 20, 0); 
  73.           SendMessage(hwndTrack, TBM_SETPOS, TRUE, 150);  
  74.           break;
  76.       case WM_SIZE:
  78.           SetWindowPos(hwndBurn, NULL, 0, HIWORD(lParam)-30, 
  79.               LOWORD(lParam), 30, SWP_NOZORDER);
  80.           break;
  82.       case WM_HSCROLL:
  84.           g_pos = SendMessage(hwndTrack, TBM_GETPOS, 0, 0);
  85.           InvalidateRect(hwndBurn, NULL, TRUE);
  86.           break;            
  88.       case WM_DESTROY:
  90.           PostQuitMessage(0);
  91.           break; 
  92.   }
  94.   return DefWindowProcW(hwnd, msg, wParam, lParam);
  95. }
  97. LRESULT CALLBACK PanelProc(HWND hwnd, UINT msg, 
  98.     WPARAM wParam, LPARAM lParam)
  99. {
  100.   HBRUSH hBrushYellow, hBrushRed, holdBrush;
  101.   HPEN hPen, holdPen;
  102.   HFONT hFont, holdFont;
  103.   PAINTSTRUCT ps;
  104.   RECT rect, rect2;
  106.   wchar_t *cap[] = { L"75", L"150", L"225", L"300", L"375", L"450", 
  107.       L"525", L"600", L"675"};
  109.   HDC hdc;
  110.   int till;
  111.   int step, full;
  112.   int i;
  114.   switch(msg)  
  115.   {
  116.     case WM_PAINT:
  118.         hdc = BeginPaint(hwnd, &ps);
  120.         GetClientRect(hwnd, &rect);
  122.         till = (rect.right / 750.0) * g_pos;
  123.         step = rect.right / 10.0;
  124.         full = (rect.right / 750.0) * 700;
  126.         hBrushYellow = CreateSolidBrush(RGB(255, 255, 184));
  127.         hBrushRed = CreateSolidBrush(RGB(255, 110, 110));
  129.         hPen = CreatePen(PS_NULL, 1, RGB(0, 0, 0));
  130.         holdPen = SelectObject(hdc, hPen);
  132.         hFont = CreateFontW(13, 0, 0, 0, FW_MEDIUM, 0, 0, 0, 0, 
  133.                 0, 0, 0, 0, L"Tahoma");
  135.         holdFont = SelectObject(hdc, hFont);
  137.         if(till > full) {
  139.             SelectObject(hdc, hBrushYellow);
  140.             Rectangle(hdc, 0, 0, full, 30);
  141.             holdBrush = SelectObject(hdc, hBrushRed);
  142.             Rectangle(hdc, full, 0, till, 30);
  144.         } else {
  146.             holdBrush = SelectObject(hdc, hBrushYellow);
  147.             Rectangle(hdc, 0, 0, till, 30);
  148.         }
  150.         SelectObject(hdc, holdPen);
  152.         for ( i = 1; i < 10; i++) {
  154.           MoveToEx(hdc, i*step, 0, NULL);
  155.           LineTo(hdc, i*step, 7);
  157.           rect2.bottom = 28;
  158.           rect2.top = 8;
  159.           rect2.left = i*step-10;
  160.           rect2.right = i*step+10;
  162.           SetBkMode(hdc, TRANSPARENT) ;
  163.           DrawTextW(hdc, cap[i-1], wcslen(cap[i-1]), &rect2, DT_CENTER);
  164.         }
  166.         SelectObject(hdc, holdBrush);
  167.         DeleteObject(hBrushYellow);
  168.         DeleteObject(hBrushRed);
  170.         DeleteObject(hPen);
  172.         SelectObject(hdc, holdFont);
  173.         DeleteObject(hFont);
  175.         EndPaint(hwnd, &ps);
  176.         break;
  177.   }
  179.   return DefWindowProcW(hwnd, msg, wParam, lParam);
  180. }

在我们的示例中，我们显示一个轨迹栏控件和我们的自定义刻录控件。 跟踪栏控件用于控制刻录控件的状态。

刻录控件是一个简单的窗口。 它放置在父窗口的底部。 它在WM_PAINT消息期间被完全绘制。 使用 GDI 函数调用绘制线条，文本和背景。

Windows API 中的自定义控件 - 图1

图：刻录控件

在 Windows API 教程的这一部分中，我们创建了刻录自定义控件。