Moduler>Arkitektur>C/WinAPI
C program mot Windows API
Programmet er skrevet i C og gjør ikke annet enn å vise fram noen røde prikker, det har to menyer og en dialogboks (About). Merk at dette programmet kan lastes opp i Visual Studio/.net, kompilerer og kjører.
Alle C-programmer skal ha en header fil, dots.h:
/*************************************************************\ * generic.h: Header file for Generic * * * * * \*************************************************************/ /******* Menu Defines *******/ #define IDM_ABOUT 1000 #define IDM_EXIT 1001
Selve C-koden inneholder initialisering og en løkke som plukker opp begivenheter (WinMain) og en lang switch for å tolke og utføre begivenheter (MainWndProc).
/********************************************************************\
* cdots.c: Source code for cdots *
* *
* Comments: simple Win32-based Application *
* distribute a set of red spots whenever painted *
* *
* Functions: *
* WinMain - Application entry point *
* MainWndProc - main window procedure *
* AboutDlgProc - dialog procedure for About dialog *
* *
* *
\********************************************************************/
/********************* Header Files *********************/
#include <windows.h>
#include "cdots.h"
/********************* Prototypes ***********************/
LRESULT WINAPI MainWndProc( HWND, UINT, WPARAM, LPARAM );
LRESULT WINAPI AboutDlgProc( HWND, UINT, WPARAM, LPARAM );
/******************* Global Variables ********************/
HANDLE ghInstance;
/********************************************************************\
* Function: int PASCAL WinMain(HINSTANCE, HINSTANCE, LPSTR, int) *
* *
* Purpose: Initializes Application *
* *
* Comments: Register window class, create and display the main *
* window, and enter message loop. *
* *
* *
\********************************************************************/
int PASCAL WinMain( HINSTANCE hInstance,
HINSTANCE hPrevInstance,
LPSTR lpszCmdLine,
int nCmdShow )
{
WNDCLASS wc;
MSG msg;
HWND hWnd;
if( !hPrevInstance )
{
wc.lpszClassName = "GenericAppClass";
wc.lpfnWndProc = MainWndProc;
wc.style = CS_OWNDC | CS_VREDRAW | CS_HREDRAW;
wc.hInstance = hInstance;
wc.hIcon = LoadIcon( NULL, IDI_APPLICATION );
wc.hCursor = LoadCursor( NULL, IDC_ARROW );
wc.hbrBackground = (HBRUSH)( COLOR_WINDOW+1 );
wc.lpszMenuName = "GenericAppMenu";
wc.cbClsExtra = 0;
wc.cbWndExtra = 0;
RegisterClass( &wc );
}
ghInstance = hInstance;
hWnd = CreateWindow( "GenericAppClass",
"Generic Application",
WS_OVERLAPPEDWINDOW|WS_HSCROLL|WS_VSCROLL,
0,
0,
CW_USEDEFAULT,
CW_USEDEFAULT,
NULL,
NULL,
hInstance,
NULL
);
ShowWindow( hWnd, nCmdShow );
while( GetMessage( &msg, NULL, 0, 0 ) ) {
TranslateMessage( &msg );
DispatchMessage( &msg );
}
return msg.wParam;
}
/********************************************************************\
* Function: LRESULT CALLBACK MainWndProc(HWND, UINT, WPARAM, LPARAM) *
* *
* Purpose: Processes Application Messages *
* *
* Comments: The following messages are processed *
* *
* WM_PAINT *
* WM_COMMAND *
* WM_DESTROY *
* *
* *
\********************************************************************/
LRESULT CALLBACK MainWndProc( HWND hWnd, UINT msg, WPARAM wParam,
LPARAM lParam )
{
PAINTSTRUCT ps;
HDC hDC;
int ix;
RECT R;
HBRUSH newBrush;
HBRUSH oldBrush;
switch( msg ) {
/**************************************************************\
* WM_PAINT: *
\**************************************************************/
case WM_PAINT:
hDC = BeginPaint( hWnd, &ps );
GetClientRect(hWnd,(LPRECT)&R);
newBrush=CreateSolidBrush(RGB(255,0,0));
oldBrush=SelectObject(hDC,newBrush);
// make 20 dots
for(ix=0;ix<20;ix++)
{
// where ?
int x=10+rand()%(R.right-R.left-20);
int y=10+rand()%(R.bottom-R.top-20);
Ellipse(hDC,x-10,y-10,x+10,y+10);
}
SelectObject(hDC,oldBrush);
EndPaint( hWnd, &ps );
break;
/**************************************************************\
* WM_COMMAND: *
\**************************************************************/
case WM_COMMAND:
switch( wParam ) {
case IDM_ABOUT:
DialogBox( ghInstance, "AboutDlg", hWnd, (DLGPROC)
AboutDlgProc );
break;
case IDM_EXIT:
PostQuitMessage( 0 );
break;
}
break;
/**************************************************************\
* WM_DESTROY: PostQuitMessage() is called *
\**************************************************************/
case WM_DESTROY:
PostQuitMessage( 0 );
break;
/**************************************************************\
* Let the default window proc handle all other messages *
\**************************************************************/
default:
return( DefWindowProc( hWnd, msg, wParam, lParam ));
}
return 0;
}
/********************************************************************\
* Function: LRESULT CALLBACK AboutDlgProc(HWND, UINT, WPARAM, LPARAM)*
* *
* Purpose: Processes "About" Dialog Box Messages *
* *
* Comments: The About dialog box is displayed when the user clicks *
* About from the Help menu. *
* *
\********************************************************************/
LRESULT CALLBACK AboutDlgProc( HWND hDlg,
UINT uMsg,
WPARAM wParam,
LPARAM lParam )
{
switch( uMsg ) {
case WM_INITDIALOG:
return TRUE;
case WM_COMMAND:
switch( wParam ) {
case IDOK:
EndDialog( hDlg, TRUE );
return TRUE;
}
break;
}
return FALSE;
}
Alle ressursene til programmet, i dette tilfellet menyer og dialogboks, er beskrevet tekstlig i en ressursfil. I starten fantes ingen GUI- eller ressurseditor som kunne hjelpe til med dette.
// Microsoft Visual C++ generated resource script.
//
#include "resource.h"
#define APSTUDIO_READONLY_SYMBOLS
/////////////////////////////////////////////////////////////////////////////
//
// Generated from the TEXTINCLUDE 2 resource.
//
#include "afxres.h"
/////////////////////////////////////////////////////////////////////////////
#undef APSTUDIO_READONLY_SYMBOLS
/////////////////////////////////////////////////////////////////////////////
// Norwegian (Bokmal) resources
#if !defined(AFX_RESOURCE_DLL) || defined(AFX_TARG_NOR)
#ifdef _WIN32
LANGUAGE LANG_NORWEGIAN, SUBLANG_NORWEGIAN_BOKMAL
#pragma code_page(1252)
#endif //_WIN32
/////////////////////////////////////////////////////////////////////////////
//
// Dialog
//
ABOUTDLG DIALOGEX 6, 21, 198, 99
STYLE DS_SETFONT|DS_MODALFRAME|DS_FIXEDSYS|WS_POPUP|WS_VISIBLE|WS_CAPTION|WS_SYSMENU
CAPTION "About Generic"
FONT 8, "MS Shell Dlg", 0, 0, 0x0
BEGIN
DEFPUSHBUTTON "&OK",IDOK,72,74,40,14
LTEXT "CDOTS",104,45,14,128,8
LTEXT "Et eksempel program",105,44,27,59,8
LTEXT "B Stenseth",106,45,45,98,8
LTEXT "for lenge siden",107,45,54,138,8
END
/////////////////////////////////////////////////////////////////////////////
//
// Menu
//
GENERICAPPMENU MENU
BEGIN
POPUP "&File"
BEGIN
MENUITEM "&Exit", IDM_EXIT
END
POPUP "&Help"
BEGIN
MENUITEM "&About", IDM_ABOUT
END
END
#ifdef APSTUDIO_INVOKED
/////////////////////////////////////////////////////////////////////////////
//
// TEXTINCLUDE
//
1 TEXTINCLUDE
BEGIN
"resource.h\0"
END
3 TEXTINCLUDE
BEGIN
"\r\n"
END
#endif // APSTUDIO_INVOKED
#endif // Norwegian (Bokmal) resources
/////////////////////////////////////////////////////////////////////////////
#ifndef APSTUDIO_INVOKED
/////////////////////////////////////////////////////////////////////////////
//
// Generated from the TEXTINCLUDE 3 resource.
//
/////////////////////////////////////////////////////////////////////////////
#endif // not APSTUDIO_INVOKED
