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/*
* A basic example of Win32 programming in C.
*
* This source code is in the PUBLIC DOMAIN and has NO WARRANTY.
*
* Colin Peters <colin@bird.fu.is.saga-u.ac.jp>
*/
#include <windows.h>
#include <string.h>
/*
* This is the window function for the main window. Whenever a message is
* dispatched using DispatchMessage (or sent with SendMessage) this function
* gets called with the contents of the message.
*/
LRESULT CALLBACK
MainWndProc (HWND hwnd, UINT nMsg, WPARAM wParam, LPARAM lParam)
{
/* The window handle for the "Click Me" button. */
static HWND hwndButton = 0;
static int cx, cy; /* Height and width of our button. */
HDC hdc; /* A device context used for drawing */
PAINTSTRUCT ps; /* Also used during window drawing */
RECT rc; /* A rectangle used during drawing */
/*
* Perform processing based on what kind of message we got.
*/
switch (nMsg)
{
case WM_CREATE:
{
/* The window is being created. Create our button
* window now. */
TEXTMETRIC tm;
/* First we use the system fixed font size to choose
* a nice button size. */
hdc = GetDC (hwnd);
SelectObject (hdc, GetStockObject (SYSTEM_FIXED_FONT));
GetTextMetrics (hdc, &tm);
cx = tm.tmAveCharWidth * 30;
cy = (tm.tmHeight + tm.tmExternalLeading) * 2;
ReleaseDC (hwnd, hdc);
/* Now create the button */
hwndButton = CreateWindow (
"button", /* Builtin button class */
"Click Here",
WS_CHILD | WS_VISIBLE | BS_PUSHBUTTON,
0, 0, cx, cy,
hwnd, /* Parent is this window. */
(HMENU) 1, /* Control ID: 1 */
((LPCREATESTRUCT) lParam)->hInstance,
NULL
);
return 0;
break;
}
case WM_DESTROY:
/* The window is being destroyed, close the application
* (the child button gets destroyed automatically). */
PostQuitMessage (0);
return 0;
break;
case WM_PAINT:
/* The window needs to be painted (redrawn). */
hdc = BeginPaint (hwnd, &ps);
GetClientRect (hwnd, &rc);
/* Draw "Hello, World" in the middle of the upper
* half of the window. */
rc.bottom = rc.bottom / 2;
DrawText (hdc, "Hello, World", -1, &rc,
DT_SINGLELINE | DT_CENTER | DT_VCENTER);
EndPaint (hwnd, &ps);
return 0;
break;
case WM_SIZE:
/* The window size is changing. If the button exists
* then place it in the center of the bottom half of
* the window. */
if (hwndButton &&
(wParam == SIZEFULLSCREEN ||
wParam == SIZENORMAL)
)
{
rc.left = (LOWORD(lParam) - cx) / 2;
rc.top = HIWORD(lParam) * 3 / 4 - cy / 2;
MoveWindow (
hwndButton,
rc.left, rc.top, cx, cy, TRUE);
}
break;
case WM_COMMAND:
/* Check the control ID, notification code and
* control handle to see if this is a button click
* message from our child button. */
if (LOWORD(wParam) == 1 &&
HIWORD(wParam) == BN_CLICKED &&
(HWND) lParam == hwndButton)
{
/* Our button was clicked. Close the window. */
DestroyWindow (hwnd);
}
return 0;
break;
}
/* If we don't handle a message completely we hand it to the system
* provided default window function. */
return DefWindowProc (hwnd, nMsg, wParam, lParam);
}
int STDCALL
WinMain (HINSTANCE hInst, HINSTANCE hPrev, LPSTR lpCmd, int nShow)
{
HWND hwndMain; /* Handle for the main window. */
MSG msg; /* A Win32 message structure. */
WNDCLASSEX wndclass; /* A window class structure. */
char* szMainWndClass = "WinTestWin";
/* The name of the main window class */
/*
* First we create a window class for our main window.
*/
/* Initialize the entire structure to zero. */
memset (&wndclass, 0, sizeof(WNDCLASSEX));
/* This class is called WinTestWin */
wndclass.lpszClassName = szMainWndClass;
/* cbSize gives the size of the structure for extensibility. */
wndclass.cbSize = sizeof(WNDCLASSEX);
/* All windows of this class redraw when resized. */
wndclass.style = CS_HREDRAW | CS_VREDRAW;
/* All windows of this class use the MainWndProc window function. */
wndclass.lpfnWndProc = MainWndProc;
/* This class is used with the current program instance. */
wndclass.hInstance = hInst;
/* Use standard application icon and arrow cursor provided by the OS */
wndclass.hIcon = LoadIcon (NULL, IDI_APPLICATION);
wndclass.hIconSm = LoadIcon (NULL, IDI_APPLICATION);
wndclass.hCursor = LoadCursor (NULL, IDC_ARROW);
/* Color the background white */
wndclass.hbrBackground = (HBRUSH) GetStockObject (WHITE_BRUSH);
/*
* Now register the window class for use.
*/
RegisterClassEx (&wndclass);
/*
* Create our main window using that window class.
*/
hwndMain = CreateWindow (
szMainWndClass, /* Class name */
"Hello", /* Caption */
WS_OVERLAPPEDWINDOW, /* Style */
CW_USEDEFAULT, /* Initial x (use default) */
CW_USEDEFAULT, /* Initial y (use default) */
CW_USEDEFAULT, /* Initial x size (use default) */
CW_USEDEFAULT, /* Initial y size (use default) */
NULL, /* No parent window */
NULL, /* No menu */
hInst, /* This program instance */
NULL /* Creation parameters */
);
/*
* Display the window which we just created (using the nShow
* passed by the OS, which allows for start minimized and that
* sort of thing).
*/
ShowWindow (hwndMain, nShow);
UpdateWindow (hwndMain);
/*
* The main message loop. All messages being sent to the windows
* of the application (or at least the primary thread) are retrieved
* by the GetMessage call, then translated (mainly for keyboard
* messages) and dispatched to the appropriate window procedure.
* This is the simplest kind of message loop. More complex loops
* are required for idle processing or handling modeless dialog
* boxes. When one of the windows calls PostQuitMessage GetMessage
* will return zero and the wParam of the message will be filled
* with the argument to PostQuitMessage. The loop will end and
* the application will close.
*/
while (GetMessage (&msg, NULL, 0, 0))
{
TranslateMessage (&msg);
DispatchMessage (&msg);
}
return msg.wParam;
}
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