Пример приложений на чистом API

Code:

program PlainAPI;

uses

Windows,

Messages;

{$R *.res}

function PlainWinProc (hWnd: THandle; nMsg: UINT;

wParam, lParam: Cardinal): Cardinal; export; stdcall;

var

hdc: THandle;

ps: TPaintStruct;

begin

Result := 0;

case nMsg of

   wm_lButtonDown:

     MessageBox (hWnd, 'Mouse Clicked',

       'Plain API', MB_OK);

   wm_Paint:

   begin

     hdc := BeginPaint (hWnd, ps);

     Ellipse (hdc, 100, 100, 300, 300);

     EndPaint (hWnd, ps);

   end;

   wm_Destroy:

     PostQuitMessage (0);

   else

     Result := DefWindowProc (hWnd, nMsg, wParam, lParam);

end;

end;

procedure WinMain;

var

hWnd: THandle;

Msg: TMsg;

WndClassEx: TWndClassEx;

begin

// initialize the window class structure

WndClassEx.cbSize := sizeOf (TWndClassEx);

WndClassEx.lpszClassName := 'PlainWindow';

WndClassEx.style := cs_VRedraw or cs_HRedraw;

WndClassEx.hInstance := HInstance;

WndClassEx.lpfnWndProc := @PlainWinProc;

WndClassEx.cbClsExtra := 0;

WndClassEx.cbWndExtra := 0;

WndClassEx.hIcon := LoadIcon (hInstance,

   MakeIntResource ('MAINICON'));

WndClassEx.hIconSm  := LoadIcon (hInstance,

   MakeIntResource ('MAINICON'));

WndClassEx.hCursor := LoadCursor (0, idc_Arrow);;

WndClassEx.hbrBackground := GetStockObject (white_Brush);

WndClassEx.lpszMenuName := nil;

// register the class

if RegisterClassEx (WndClassEx) = 0 then

   MessageBox (0, 'Invalid class registration',

     'Plain API', MB_OK)

else

begin

   hWnd := CreateWindowEx (

     ws_Ex_OverlappedWindow, // extended styles

     WndClassEx.lpszClassName, // class name

     'Plain API Demo', // title

     ws_OverlappedWindow, // styles

     cw_UseDefault, 0, // position

     cw_UseDefault, 0, // size

     0, // parent window

     0, // menu

     HInstance, // instance handle

     nil); // initial parameters

   if hWnd = 0 then

     MessageBox (0, 'Window not created',

       'Plain API', MB_OK)

   else

   begin

     ShowWindow (hWnd, sw_ShowNormal);

     while GetMessage (Msg, 0, 0, 0) do

     begin

       TranslateMessage (Msg);

       DispatchMessage (Msg);

     end;

   end;

end;

end;

begin

WinMain;

end.