程序9-2 OWNDRAW
OWNDRAW.C /*------------------------------------------------------------------------ OWNDRAW.C -- Owner-Draw Button Demo Program (c) Charles Petzold, 1996 -------------------------------------------------------------------------*/ #include <windows.h> #define ID_SMALLER 1 #define ID_LARGER 2 #define BTN_WIDTH ( 8 * cxChar) #define BTN_HEIGHT ( 4 * cyChar) LRESULT CALLBACK WndProc (HWND, UINT, WPARAM, LPARAM) ; HINSTANCE hInst ; int WINAPI WinMain (HINSTANCE hInstance, HINSTANCE hPrevInstance, PSTR szCmdLine, int iCmdShow) { static TCHAR szAppName[] = TEXT ("OwnDraw") ; MSG msg ; HWND hwnd ; WNDCLASS wndclass ; hInst = hInstance ; wndclass.style = CS_HREDRAW | CS_VREDRAW ; wndclass.lpfnWndProc = WndProc ; wndclass.cbClsExtra = 0 ; wndclass.cbWndExtra = 0 ; wndclass.hInstance = hInstance ; wndclass.hIcon = LoadIcon (NULL, IDI_APPLICATION) ; wndclass.hCursor = LoadCursor (NULL, IDC_ARROW) ; wndclass.hbrBackground = (HBRUSH) GetStockObject (WHITE_BRUSH) ; wndclass.lpszMenuName = szAppName ; wndclass.lpszClassName = szAppName ; if (!RegisterClass (&wndclass)) { MessageBox ( NULL, TEXT ("This program requires Windows NT!"), szAppName, MB_ICONERROR) ; return 0 ; } hwnd = CreateWindow (szAppName, TEXT ("Owner-Draw Button Demo"), WS_OVERLAPPEDWINDOW, CW_USEDEFAULT, CW_USEDEFAULT, CW_USEDEFAULT, CW_USEDEFAULT, NULL, NULL, hInstance, NULL) ; ShowWindow (hwnd, iCmdShow) ; UpdateWindow (hwnd) ; while (GetMessage (&msg, NULL, 0, 0)) { TranslateMessage (&msg) ; DispatchMessage (&msg) ; } return msg.wParam ; } void Triangle (HDC hdc, POINT pt[]) { SelectObject (hdc, GetStockObject (BLACK_BRUSH)) ; Polygon (hdc, pt, 3) ; SelectObject (hdc, GetStockObject (WHITE_BRUSH)) ; } LRESULT CALLBACK WndProc (HWND hwnd, UINT message, WPARAM wParam,LPARAM lParam) { static HWND hwndSmaller, hwndLarger ; static int cxClient, cyClient, cxChar, cyChar ; int cx, cy ; LPDRAWITEMSTRUCT pdis ; POINT pt[3] ; RECT rc ; switch (message) { case WM_CREATE : cxChar = LOWORD (GetDialogBaseUnits ()) ; cyChar = HIWORD (GetDialogBaseUnits ()) ; // Create the owner-draw pushbuttons hwndSmaller = CreateWindow (TEXT ("button"), TEXT (""), WS_CHILD | WS_VISIBLE | BS_OWNERDRAW, 0, 0, BTN_WIDTH, BTN_HEIGHT, hwnd, (HMENU) ID_SMALLER, hInst, NULL) ; hwndLarger = CreateWindow (TEXT ("button"), TEXT (""), WS_CHILD | WS_VISIBLE | BS_OWNERDRAW, 0, 0, BTN_WIDTH, BTN_HEIGHT, hwnd, (HMENU) ID_LARGER, hInst, NULL) ; return 0 ; case WM_SIZE : cxClient = LOWORD (lParam) ; cyClient = HIWORD (lParam) ; // Move the buttons to the new center MoveWindow ( hwndSmaller, cxClient / 2 - 3 * BTN_WIDTH / 2, cyClient / 2 - BTN_HEIGHT / 2, BTN_WIDTH, BTN_HEIGHT, TRUE) ; MoveWindow ( hwndLarger, cxClient / 2 + BTN_WIDTH / 2,cyClient / 2 - BTN_HEIGHT / 2, BTN_WIDTH, BTN_HEIGHT, TRUE) ; return 0 ; case WM_COMMAND : GetWindowRect (hwnd, &rc) ; // Make the window 10% smaller or larger switch (wParam) { case ID_SMALLER : rc.left += cxClient / 20 ; rc.right -= cxClient / 20 ; rc.top += cyClient / 20 ; rc.bottom -= cyClient / 20 ; break ; case ID_LARGER : rc.left -= cxClient / 20 ; rc.right += cxClient / 20 ; rc.top -= cyClient / 20 ; rc.bottom += cyClient / 20 ; break ; } MoveWindow ( hwnd, rc.left, rc.top, rc.right - rc.left, rc.bottom - rc.top, TRUE) ; return 0 ; case WM_DRAWITEM : pdis = (LPDRAWITEMSTRUCT) lParam ; // Fill area with white and frame it black FillRect (pdis->hDC, &pdis->rcItem, (HBRUSH) GetStockObject (WHITE_BRUSH)) ; FrameRect ( pdis->hDC, &pdis->rcItem, ( HBRUSH) GetStockObject (BLACK_BRUSH)) ; // Draw inward and outward black triangles cx = pdis->rcItem.right - pdis->rcItem.left ; cy = pdis->rcItem.bottom - pdis->rcItem.top ; switch (pdis->CtlID) { case ID_SMALLER : pt[0].x = 3 * cx / 8 ; pt[0].y = 1 * cy / 8 ; pt[1].x = 5 * cx / 8 ; pt[1].y = 1 * cy / 8 ; pt[2].x = 4 * cx / 8 ; pt[2].y = 3 * cy / 8 ; Triangle (pdis->hDC, pt) ; pt[0].x = 7 * cx / 8 ; pt[0].y = 3 * cy / 8 ; pt[1].x = 7 * cx / 8 ; pt[1].y = 5 * cy / 8 ; pt[2].x = 5 * cx / 8 ; pt[2].y = 4 * cy / 8 ; Triangle (pdis->hDC, pt) ; pt[0].x = 5 * cx / 8 ; pt[0].y = 7 * cy / 8 ; pt[1].x = 3 * cx / 8 ; pt[1].y = 7 * cy / 8 ; pt[2].x = 4 * cx / 8 ; pt[2].y = 5 * cy / 8 ; Triangle (pdis->hDC, pt) ; pt[0].x = 1 * cx / 8 ; pt[0].y = 5 * cy / 8 ; pt[1].x = 1 * cx / 8 ; pt[1].y = 3 * cy / 8 ; pt[2].x = 3 * cx / 8 ; pt[2].y = 4 * cy / 8 ; Triangle (pdis->hDC, pt) ; break ; case ID_LARGER : pt[0].x = 5 * cx / 8 ; pt[0].y = 3 * cy / 8 ; pt[1].x = 3 * cx / 8 ; pt[1].y = 3 * cy / 8 ; pt[2].x = 4 * cx / 8 ; pt[2].y = 1 * cy / 8 ; Triangle (pdis->hDC, pt) ; pt[0].x = 5 * cx / 8 ; pt[0].y = 5 * cy / 8 ; pt[1].x = 5 * cx / 8 ; pt[1].y = 3 * cy / 8 ; pt[2].x = 7 * cx / 8 ; pt[2].y = 4 * cy / 8 ; Triangle (pdis->hDC, pt) ; pt[0].x = 3 * cx / 8 ; pt[0].y = 5 * cy / 8 ; pt[1].x = 5 * cx / 8 ; pt[1].y = 5 * cy / 8 ; pt[2].x = 4 * cx / 8 ; pt[2].y = 7 * cy / 8 ; Triangle (pdis->hDC, pt) ; pt[0].x = 3 * cx / 8 ; pt[0].y = 3 * cy / 8 ; pt[1].x = 3 * cx / 8 ; pt[1].y = 5 * cy / 8 ; pt[2].x = 1 * cx / 8 ; pt[2].y = 4 * cy / 8 ; Triangle (pdis->hDC, pt) ; break ; } // Invert the rectangle if the button is selected if (pdis->itemState & ODS_SELECTED) InvertRect (pdis->hDC, &pdis->rcItem) ; // Draw a focus rectangle if the button has the focus if (pdis->itemState & ODS_FOCUS) { pdis->rcItem.left += cx / 16 ; pdis->rcItem.top += cy / 16 ; pdis->rcItem.right -= cx / 16 ; pdis->rcItem.bottom-= cy / 16 ; DrawFocusRect (pdis->hDC, &pdis->rcItem) ; } return 0 ; case WM_DESTROY : PostQuitMessage (0) ; return 0 ; } return DefWindowProc (hwnd, message, wParam, lParam) ; }