about2.c

Programming Windows 程序开发设计指南

/*------------------------------------------
   ABOUT2.C -- About Box Demo Program No. 2
               (c) Charles Petzold, 1996
  ------------------------------------------*/

#include <windows.h>
#include "about2.h"

LRESULT CALLBACK WndProc      (HWND, UINT, WPARAM, LPARAM) ;
BOOL    CALLBACK AboutDlgProc (HWND, UINT, WPARAM, LPARAM) ;

int iCurrentColor  = IDD_BLACK,
    iCurrentFigure = IDD_RECT ;

int WINAPI WinMain (HINSTANCE hInstance, HINSTANCE hPrevInstance,
                    PSTR szCmdLine, int iCmdShow)
     {
     static char  szAppName[] = "About2" ;
     MSG          msg ;
     HWND         hwnd ;
     WNDCLASSEX   wndclass ;

     wndclass.cbSize        = sizeof (wndclass) ;
     wndclass.style         = CS_HREDRAW | CS_VREDRAW ;
     wndclass.lpfnWndProc   = WndProc ;
     wndclass.cbClsExtra    = 0 ;
     wndclass.cbWndExtra    = 0 ;
     wndclass.hInstance     = hInstance ;
     wndclass.hIcon         = LoadIcon (hInstance, szAppName) ;
     wndclass.hCursor       = LoadCursor (NULL, IDC_ARROW) ;
     wndclass.hbrBackground = (HBRUSH) GetStockObject (WHITE_BRUSH) ;
     wndclass.lpszMenuName  = szAppName ;
     wndclass.lpszClassName = szAppName ;
     wndclass.hIconSm       = LoadIcon (hInstance, szAppName) ;

     RegisterClassEx (&wndclass) ;

     hwnd = CreateWindow (szAppName, "About Box Demo Program",
                          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 PaintWindow (HWND hwnd, int iColor, int iFigure)
     {
     static COLORREF crColor[8] = { RGB (0,     0, 0), RGB (  0,   0, 255),
                                    RGB (0,   255, 0), RGB (  0, 255, 255),
                                    RGB (255,   0, 0), RGB (255,   0, 255),
                                    RGB (255, 255, 0), RGB (255, 255, 255) } ;
     HBRUSH          hBrush ;
     HDC             hdc ;
     RECT            rect ;

     hdc = GetDC (hwnd) ;
     GetClientRect (hwnd, &rect) ;
     hBrush = CreateSolidBrush (crColor[iColor - IDD_BLACK]) ;
     hBrush = (HBRUSH) SelectObject (hdc, hBrush) ;

     if (iFigure == IDD_RECT)
          Rectangle (hdc, rect.left, rect.top, rect.right, rect.bottom) ;
     else
          Ellipse   (hdc, rect.left, rect.top, rect.right, rect.bottom) ;

     DeleteObject (SelectObject (hdc, hBrush)) ;
     ReleaseDC (hwnd, hdc) ;
     }

void PaintTheBlock (HWND hCtrl, int iColor, int iFigure)
     {
     InvalidateRect (hCtrl, NULL, TRUE) ;
     UpdateWindow (hCtrl) ;
     PaintWindow (hCtrl, iColor, iFigure) ;
     }

LRESULT CALLBACK WndProc (HWND hwnd, UINT iMsg, WPARAM wParam, LPARAM lParam)
     {
     static HINSTANCE hInstance ;
     PAINTSTRUCT      ps ;

     switch (iMsg)
          {
          case WM_CREATE :
               hInstance = ((LPCREATESTRUCT) lParam)->hInstance ;
               return 0 ;

          case WM_COMMAND :
               switch (LOWORD (wParam))
                    {
                    case IDM_ABOUT :
                         if (DialogBox (hInstance, "AboutBox", hwnd,
                                        AboutDlgProc))
                              InvalidateRect (hwnd, NULL, TRUE) ;
                         return 0 ;
                    }
               break ;

          case WM_PAINT :
               BeginPaint (hwnd, &ps) ;
               EndPaint (hwnd, &ps) ;

               PaintWindow (hwnd, iCurrentColor, iCurrentFigure) ;
               return 0 ;
                    
          case WM_DESTROY :
               PostQuitMessage (0) ;
               return 0 ;
          }
     return DefWindowProc (hwnd, iMsg, wParam, lParam) ;
     }

BOOL CALLBACK AboutDlgProc (HWND hDlg, UINT iMsg, WPARAM wParam, LPARAM lParam)
     {
     static HWND hCtrlBlock ;
     static int  iColor, iFigure ;

     switch (iMsg)
          {
          case WM_INITDIALOG :
               iColor  = iCurrentColor ;
               iFigure = iCurrentFigure ;

               CheckRadioButton (hDlg, IDD_BLACK, IDD_WHITE, iColor) ;
               CheckRadioButton (hDlg, IDD_RECT,  IDD_ELL,   iFigure) ;

               hCtrlBlock = GetDlgItem (hDlg, IDD_PAINT) ;

               SetFocus (GetDlgItem (hDlg, iColor)) ;
               return FALSE ;

          case WM_COMMAND :
               switch (LOWORD (wParam))
                    {
                    case IDOK :
                         iCurrentColor  = iColor ;
                         iCurrentFigure = iFigure ;
                         EndDialog (hDlg, TRUE) ;
                         return TRUE ;

                    case IDCANCEL :
                         EndDialog (hDlg, FALSE) ;
                         return TRUE ;

                    case IDD_BLACK :
                    case IDD_RED :
                    case IDD_GREEN :
                    case IDD_YELLOW :
                    case IDD_BLUE :
                    case IDD_MAGENTA :
                    case IDD_CYAN :
                    case IDD_WHITE :
                         iColor = LOWORD (wParam) ;
                         CheckRadioButton (hDlg, IDD_BLACK, IDD_WHITE, LOWORD (wParam)) ;
                         PaintTheBlock (hCtrlBlock, iColor, iFigure) ;
                         return TRUE ;

                    case IDD_RECT :
                    case IDD_ELL :
                         iFigure = LOWORD (wParam) ;
                         CheckRadioButton (hDlg, IDD_RECT, IDD_ELL, LOWORD (wParam)) ;
                         PaintTheBlock (hCtrlBlock, iColor, iFigure) ;
                         return TRUE ;
                    }
               break ;

          case WM_PAINT :
               PaintTheBlock (hCtrlBlock, iColor, iFigure) ;
               break ;
          }
     return FALSE ;
     }