' ======================================================
'  Sample Windows API program
'  by MystikShadows
' ======================================================
Option explicit
Option private

' ------------------------
'  This include is a must
' ------------------------
#include once "windows.bi"

'Const CB_ADDSTRING = &H143
'Const CB_SETITEMDATA = &H151

DECLARE FUNCTION WinMain ( BYVAL hInstance     AS HINSTANCE, _
                           BYVAL hPrevInstance AS HINSTANCE, _
                           szCmdLine           AS STRING, _
                           BYVAL iCmdShow      AS INTEGER ) AS INTEGER

' ------------------------------
'  Shared Variable Declarations
' ------------------------------
DIM SHARED StaticLabel          AS UINTEGER
DIM SHARED EditControl          AS UINTEGER
DIM SHARED OKButtonHandle       AS UINTEGER

' ------------------------------------
'  So far, only one line of main code
' ------------------------------------
END WinMain( GetModuleHandle( null ), null, COMMAND$, SW_NORMAL )

' ==========================================================
'  NAME........: WindowsCallbackProcedure
'  PARAMETERS..: BYVAL hWnd    AS HWND    Window HAndle
'                BYVAL message AS UINT    Message
'                BYVAL wParam  AS WPARAM  Message
'                BYVAL lParam  AS UINT    Message

'  RETURNS.....: 0 or the error level if any.
' ----------------------------------------------------------
'  DESCRIPTION.: This function is the windows callback
'                procedure.  It will be attached to the
'                created window when that window is
'                registered, created and shown.
' ==========================================================
FUNCTION WindowsCallbackProcedure ( BYVAL hWnd    AS HWND, _
                                    BYVAL message AS UINT, _
                                    BYVAL wParam  AS WPARAM, _
                                    BYVAL lParam  AS LPARAM ) AS LRESULT

    ' ----------------------------
    '  We'll need a few variables
    ' ----------------------------
    DIM WindowRectangle     AS RECT
    DIM WindowPaint         AS PAINTSTRUCT
    DIM DeviceContextHandle AS HDC

    FUNCTION = 0

    ' -----------------------------
    '  Message Process Select Case
    ' -----------------------------
    SELECT CASE message
           CASE WM_CREATE
                EXIT FUNCTION
           CASE WM_LBUTTONUP
                ' MessageBox NULL, "Hello world from FreeBasic", "FB Win", MB_OK
           CASE WM_PAINT
                DeviceContextHandle = BeginPaint( hWnd, @WindowPaint )
                GetClientRect( hWnd, @WindowRectangle )
                DrawText( DeviceContextHandle, _
                          "", _
                          -1, _
                          @WindowRectangle, _
                          DT_SINGLELINE Or DT_CENTER Or DT_VCENTER )
                EndPaint( hWnd, @WindowPaint )
                EXIT FUNCTION
           CASE WM_KEYDOWN
                ' --------------------------
                '  Close if esc key pressed
                ' --------------------------
                IF lobyte( wParam ) = 27  Then
                   PostMessage( hWnd, WM_CLOSE, 0, 0 )
                END IF
           CASE WM_DESTROY
                PostQuitMessage( 0 )
                EXIT FUNCTION
           CASE WM_COMMAND
                SELECT CASE lParam
                       ' -----------------------
                       '  Ok Button was clicked
                       ' -----------------------
                       CASE OKButtonHandle
                            MessageBox hWnd, "You have clicked the OK button!", "INFORMATION", 0
                END SELECT
      END SELECT

    ' ----------------------------------------------------------------
    '  If the message isn't for our program it getts sent to Window's
    '  default message handler for standard processing.
    ' ----------------------------------------------------------------
    FUNCTION = DefWindowProc( hWnd, message, wParam, lParam )

END FUNCTION

' =========================================================
'  NAME........: WinMain
'  PARAMETERS..: BYVAL hInstance     AS HINSTANCE
'                BYVAL hPrevInstance AS HINSTANCE
'                szCmdLine           AS STRING
'                BYVAL iCmdShow      AS INTEGER
'  RETURNS.....: 0 or the error level if any.
' ---------------------------------------------------------
'  DESCRIPTION.: This function is the windows callback
'                procedure.  It will be attached to the
'                created window when that window is
'                registered, created and shown.
' =========================================================
FUNCTION WinMain ( Byval hInstance     As HINSTANCE, _
                   Byval hPrevInstance As HINSTANCE, _
                   szCmdLine           As String, _
                   Byval iCmdShow      As Integer ) As Integer

    ' ---------------------
    '  Some work variables
    ' ---------------------
    DIM WindowMessage        AS MSG
    DIM WindowClass          AS WNDCLASS
    DIM ApplicationClassName AS STRING
    DIM hWnd                 AS HWND
    DIM BackgroundColor      AS INTEGER
    ' ---------------------------------------------
    '  First we populate the WindowClass structure
    ' ---------------------------------------------
    FUNCTION = 0
    BackgroundColor = &HC0C0C0
    ApplicationClassName = "Your First Window"
    WITH WindowClass
         .style         = CS_HREDRAW Or CS_VREDRAW
         .lpfnWndProc   = @WindowsCallbackProcedure
         .cbClsExtra    = 0
         .cbWndExtra    = 0
         .hInstance     = hInstance
         .hIcon         = LoadIcon( NULL, IDI_APPLICATION )
         .hCursor       = LoadCursor( NULL, IDC_ARROW )
         .hbrBackground = GetStockObject(LTGRAY_BRUSH)
         .lpszMenuName  = NULL
         .lpszClassName = STRPTR( ApplicationClassName )
    END WITH
    ' -----------------------------------
    '  Next we register the window class
    ' -----------------------------------
    IF RegisterClass( @WindowClass ) = FALSE  THEN
       MessageBox( null, "Failed to register WindowClass!", ApplicationClassName, MB_ICONERROR )
       EXIT FUNCTION
    END IF
    ' ------------------------------------
    '  We then Create and show the window
    ' ------------------------------------
    hWnd = CreateWindowEx( 0, _                     ' Extended Window Style
                           ApplicationClassName, _  ' Registered Class Name
                           "The Hello Program", _   ' Windows Title Caption
                           WS_OVERLAPPEDWINDOW, _   ' Window Style Bit
                           CW_USEDEFAULT, _         ' X Position
                           CW_USEDEFAULT, _         ' Y Position
                           CW_USEDEFAULT, _         ' Width of the window
                           CW_USEDEFAULT, _         ' Height Of the window
                           NULL, _                  ' Handle to owner window
                           NULL, _                  ' handle to menu
                           hInstance, _             ' Handle to Application Instance
                           NULL )                   ' Handle to Window Creation Data
    ' -----------------------------------------------------
    '  Right here is where we add our controls to the form
    ' -----------------------------------------------------
    StaticLabel          = CreateWindowEx(0, "STATIC", "Enter Your Name:", WS_VISIBLE Or WS_CHILD Or WS_TABSTOP, _
                                          30, 30, 200, 30, hWnd, null, hInstance, null )
    EditControl          = CreateWindowEx(0, "EDIT",   "", WS_VISIBLE Or WS_CHILD Or WS_TABSTOP Or WS_BORDER, _
                                          300,30, 200, 30, hWnd, null, hInstance, null)
    OKButtonHandle       = CreateWindowEx(0, "BUTTON", "&Ok", WS_VISIBLE Or WS_CHILD Or WS_TABSTOP, _
                                          100,300, 80, 30, hWnd, null, hInstance, null)
    ' ----------------------------------
    '  We're now ready to show the form
    ' ----------------------------------
    ShowWindow( hWnd, iCmdShow )
    UpdateWindow( hWnd )
    ' ------------------------------------------
    '  This loop processes the windows messages
    ' ------------------------------------------
    WHILE GetMessage( @WindowMessage, NULL, 0, 0 ) <> FALSE
          TranslateMessage( @WindowMessage )
          DispatchMessage( @WindowMessage )
    WEND
    ' -------------------------------------------------------------
    '  Program has ended, we return wParam to the operating system
    ' -------------------------------------------------------------
    FUNCTION = WindowMessage.wParam

END FUNCTION