// (C) Copyright 1994 by Borland International // // Cmdlg.c - Common Dialogs example in C /********************************************************************* This program has example code that makes use of the Common Dialogs available in Windows 3.1. It is meant to be a simple example using the C programming language. The main window will have menu selections for opening a file, changing the font and changing the color used for the selected font. When a file is selected the name will be displayed on the client area of the window. The files needed to build this program are . . . cmdlg.h Header file for application cmdlgr.h Header file for application and resources cmdlg.c Source file for application cmdlg.rc Resource file for application ***********************************************************************/ #include // Contains the necessary headers and definitions for this program #include "cmdlg.h" /*** Global Variables ***/ char szName[256]; COLORREF crColor; HFONT hfFont; BOOL tfFontLoaded; HINSTANCE hInst; // current instance /********************************************************************* Using the OPENFILENAME structure and the Windows 3.1 API call GetOpenFileName() eases the selection of files for the programmer and for the user. The WINHELP.EXE help file WIN31WH.HLP (found in the BORLANDC\BIN directory) contains a detailed description of the function call and its associated structure. The Flags field of the structure is particularly useful when custimization is required. **********************************************************************/ void CMUFileOpen( HWND hWnd ) { OPENFILENAME ofnTemp; DWORD Errval; // Error value char buf[5]; // Error buffer char Errstr[50]="GetOpenFileName returned Error #"; char szTemp[] = "All Files (*.*)\0*.*\0Text Files (*.txt)\0*.txt\0"; /* Note the initialization method of the above string. The GetOpenFileName() function expects to find a string in the OPENFILENAME structure that has a '\0' terminator between strings and an extra '\0' that terminates the entire filter data set. Using the technique shown below will fail because "X" is really 'X' '\0' '\0' '\0' in memory. When the GetOpenFileName() function scans szTemp it will stop after finding the extra trailing '\0' characters. char szTemp[][4] = { "X", "*.*", "ABC", "*.*", "" }; The string should be "X\0*.*\0ABC\0*.*\0". Remember that in C or C++ a quoted string is automatically terminated with a '\0' character so char "X\0"; would result in 'X' '\0' '\0' which provides the extra '\0' that GetOpenFileName() needs to see in order to terminate the scan of the string. Just 'char ch "X";' would result in 'X' '\0' and GetOpenFileName() would wander off in memory until it lucked into a '\0' '\0' character sequence. */ /* Some Windows structures require the size of themselves in an effort to provide backward compatibility with future versions of Windows. If the lStructSize member is not set the call to GetOpenFileName() will fail. */ ofnTemp.lStructSize = sizeof( OPENFILENAME ); ofnTemp.hwndOwner = hWnd; // An invalid hWnd causes non-modality ofnTemp.hInstance = 0; ofnTemp.lpstrFilter = (LPSTR)szTemp; // See previous note concerning string ofnTemp.lpstrCustomFilter = NULL; ofnTemp.nMaxCustFilter = 0; ofnTemp.nFilterIndex = 1; ofnTemp.lpstrFile = (LPSTR)szName; // Stores the result in this variable ofnTemp.nMaxFile = sizeof( szName ); ofnTemp.lpstrFileTitle = NULL; ofnTemp.nMaxFileTitle = 0; ofnTemp.lpstrInitialDir = NULL; ofnTemp.lpstrTitle = "OPENFILENAME"; // Title for dialog ofnTemp.Flags = OFN_FILEMUSTEXIST | OFN_HIDEREADONLY | OFN_PATHMUSTEXIST; ofnTemp.nFileOffset = 0; ofnTemp.nFileExtension = 0; ofnTemp.lpstrDefExt = "*"; ofnTemp.lCustData = 0L; ofnTemp.lpfnHook = NULL; ofnTemp.lpTemplateName = NULL; /* If the call to GetOpenFileName() fails you can call CommDlgExtendedError() to retrieve the type of error that occured. */ if(GetOpenFileName( &ofnTemp ) != TRUE) { Errval=CommDlgExtendedError(); if(Errval!=0) // 0 value means user selected Cancel { sprintf(buf,"%ld",Errval); strcat(Errstr,buf); MessageBox(hWnd,Errstr,"WARNING",MB_OK|MB_ICONSTOP); } } InvalidateRect( hWnd, NULL, TRUE ); // Repaint to display the new name } /************************************************************************* Using the CHOOSECOLOR structure and the Windows 3.1 API call ChooseColor(), eases the selection of colors for the programmer and for the user. The comments for the File Open dialog regarding the help file and the structure size also apply to the color dialog. **************************************************************************/ void CMUColor( HWND hWnd ) { CHOOSECOLOR ccTemp; COLORREF crTemp[16]; // Important, sometimes unused, array ccTemp.lStructSize = sizeof( CHOOSECOLOR ); ccTemp.hwndOwner = hWnd; ccTemp.hInstance = 0; ccTemp.rgbResult = crColor; // CC_RGBINIT flag makes this the default color /* lpCustColors must be set to a valid array of 16 COLORREF's, even if it is not used. If it isn't you will probably fail with a GP fault in COMMDLG.DLL. */ ccTemp.lpCustColors = crTemp; ccTemp.Flags = CC_PREVENTFULLOPEN | CC_RGBINIT; ccTemp.lCustData = 0L; ccTemp.lpfnHook = NULL; ccTemp.lpTemplateName = NULL; if( ChooseColor( &ccTemp ) == TRUE ) crColor = ccTemp.rgbResult; InvalidateRect( hWnd, NULL, TRUE ); } /************************************************************************** Using the CHOOSEFONT structure and the Windows 3.1 API call ChooseFont() eases the selection of fonts for the programmer and for the user. The comments for the File Open dialog regarding the help file and the structure size also apply to the font dialog. ***************************************************************************/ void CMUFont( HWND hWnd ) { /* The variables below are static so that multiple calls to the font dialog will retain previous user selections. */ static CHOOSEFONT cfTemp; static LOGFONT lfTemp; if( tfFontLoaded == TRUE ) // cfTemp contains previous selections { cfTemp.Flags |= CF_INITTOLOGFONTSTRUCT; cfTemp.rgbColors = crColor; } else { cfTemp.lStructSize = sizeof( CHOOSEFONT ); cfTemp.hwndOwner = hWnd; cfTemp.hDC = 0; cfTemp.lpLogFont = &lfTemp; // Store the result here cfTemp.Flags = CF_EFFECTS | CF_FORCEFONTEXIST | CF_SCREENFONTS; cfTemp.rgbColors = crColor; // Color and font dialogs use the same color cfTemp.lCustData = 0L; cfTemp.lpfnHook = NULL; cfTemp.lpTemplateName = NULL; cfTemp.hInstance = 0; cfTemp.lpszStyle = NULL; cfTemp.nFontType = SCREEN_FONTTYPE; cfTemp.nSizeMin = 0; cfTemp.nSizeMax = 0; } if( ChooseFont( &cfTemp ) == TRUE ) { if( tfFontLoaded == TRUE ) DeleteObject( hfFont ); crColor = cfTemp.rgbColors; hfFont = CreateFontIndirect( &lfTemp ); tfFontLoaded = TRUE; } InvalidateRect( hWnd, NULL, TRUE ); } /**********************************************************************/ BOOL InitApplication(HINSTANCE hInstance) { WNDCLASS wc; // Fill in window class structure with parameters that describe the // main window. wc.style = CS_HREDRAW | CS_VREDRAW; // Class style(s). wc.lpfnWndProc = (long (FAR PASCAL*)())MainWndProc; // Function to retrieve messages for // windows of this class. wc.cbClsExtra = 0; // No per-class extra data. wc.cbWndExtra = 0; // No per-window extra data. wc.hInstance = hInstance; // Application that owns the class. wc.hIcon = LoadIcon(NULL, IDI_APPLICATION); wc.hCursor = LoadCursor(NULL, IDC_ARROW); wc.hbrBackground = GetStockObject(WHITE_BRUSH); wc.lpszMenuName = "CMDLGAPMENU"; // Name of menu resource in .RC file. wc.lpszClassName = "CMDLG"; // Name used in call to CreateWindow. /* Register the window class and return success/failure code. */ return (RegisterClass(&wc)); } /************************************************************************/ BOOL InitInstance(HINSTANCE hInstance, int nCmdShow) { HWND hWnd; // Main window handle. /* Save the instance handle in static variable, which will be used in */ /* many subsequence calls from this application to Windows. */ hInst = hInstance; /* Create a main window for this application instance. */ hWnd = CreateWindow( "CMDLG", // See RegisterClass() call. "Common Dialog Example", // Text for window title bar. WS_OVERLAPPEDWINDOW, // Window style. CW_USEDEFAULT, // Default horizontal position. CW_USEDEFAULT, // Default vertical position. CW_USEDEFAULT, // Default width. CW_USEDEFAULT, // Default height. NULL, // Overlapped windows have no parent. NULL, // Use the window class menu. hInstance, // This instance owns this window. NULL // Pointer not needed. ); /* If window could not be created, return "failure" */ if (!hWnd) return (FALSE); /* Make the window visible; update its client area; and return "success" */ ShowWindow(hWnd, nCmdShow); // Show the window UpdateWindow(hWnd); // Sends WM_PAINT message return (TRUE); // Returns the value from PostQuitMessage } /**************************************************************************** FUNCTION: MainWndProc(HWND, UINT, WPARAM, LPARAM) ****************************************************************************/ LRESULT FAR PASCAL _export MainWndProc(HWND hWnd, UINT message, WPARAM wParam, LPARAM lParam) { HFONT fTemp = (HFONT)NULL; // Placeholder for the original font RECT rTemp; // Client are needed by DrawText() HDC hdc; // HDC for Window PAINTSTRUCT ps; // Paint Struct for BeginPaint call switch (message) { case WM_CREATE: // Initialize Global vars strcpy( szName, "" ); // Empty the file name string crColor = RGB( 0, 0, 0 ); // Use black as the default color hfFont = 0; // Empty the handle to the font tfFontLoaded = FALSE; // Set the font selected flag to false return 0L; case WM_PAINT: // Display the file name using the selected font in the selected color. hdc=BeginPaint(hWnd,&ps); SetTextColor( hdc, crColor ); if( tfFontLoaded == TRUE ) fTemp = (HFONT)SelectObject( hdc, hfFont ); GetClientRect( hWnd, &rTemp ); DrawText( hdc, szName, strlen( szName ), &rTemp, DT_CENTER | DT_WORDBREAK ); if( tfFontLoaded == TRUE ) SelectObject( hdc, fTemp ); EndPaint(hWnd,&ps); break; case WM_COMMAND: // message: command from application menu switch(GET_WM_COMMAND_ID(wParam, lParam)) { case CM_EXIT: DestroyWindow(hWnd); break; case CM_U_FILEOPEN: CMUFileOpen(hWnd); break; case CM_U_COLOR: CMUColor(hWnd); break; case CM_U_FONT: CMUFont(hWnd); break; case CM_U_HELPABOUT: MessageBox(hWnd,szCMDLGAPAbout,"About CMDLG",MB_OK); break; default: break; } break; case WM_QUIT: case WM_DESTROY: // message: window being destroyed if( hfFont != 0 ) DeleteObject( hfFont ); PostQuitMessage(0); break; default: // Passes it on if unproccessed return (DefWindowProc(hWnd, message, wParam, lParam)); } return 0L; } #pragma argsused /**************************************************************/ int PASCAL WinMain(HINSTANCE hInstance, HINSTANCE hPrevInstance, LPSTR lpCmdLine, int nCmdShow) { MSG msg; // message if (!hPrevInstance) // Other instances of app running? if (!InitApplication(hInstance)) // Initialize shared things return (FALSE); // Exits if unable to initialize /* Perform initializations that apply to a specific instance */ if (!InitInstance(hInstance, nCmdShow)) return (FALSE); /* Acquire and dispatch messages until a WM_QUIT message is received. */ while (GetMessage(&msg, // message structure NULL, // handle of window receiving the message 0, // lowest message to examine 0)) // highest message to examine { TranslateMessage(&msg); // Translates virtual key codes DispatchMessage(&msg); // Dispatches message to window } return (msg.wParam); // Returns the value from PostQuitMessage } // End of file cmdlg.c