Перехват мыши

Этот пример показывает как можно отслеживать - с какими окнами в системе работает   пользователь. То есть при нажатии на Титле бар , минимизации, закрытии окна.

#define STRICT
#include 
#include "resource.h"

const char *pszTitle = "Descriptor Systems Mouse Capture Example";

// internal function prototypes
LRESULT CALLBACK WndProc ( HWND hwnd, UINT iMsg
 , WPARAM wParam, LPARAM lParam );

int PASCAL WinMain ( HINSTANCE hInstance, HINSTANCE hPrevInstance
 , LPSTR lpszCmdLine, int nCmdShow )
{
HWND hwnd; // window handle
WNDCLASS wndclass; // class structure
MSG msg; // msg data structure


 // register only if this is the first instance
 if (!hPrevInstance)
 {
 wndclass.style = CS_HREDRAW | CS_VREDRAW;
 wndclass.lpfnWndProc = WndProc;
 wndclass.cbClsExtra = 0;
 wndclass.cbWndExtra = 0;
 wndclass.hInstance = hInstance;
 wndclass.hIcon = LoadIcon ( hInstance
 , MAKEINTRESOURCE ( IDI_MYICON ));
 wndclass.hCursor = LoadCursor ( 0, IDC_ARROW );
 wndclass.hbrBackground = (HBRUSH)GetStockObject ( WHITE_BRUSH );
 wndclass.lpszMenuName = MAKEINTRESOURCE ( IDM_MENU );
 wndclass.lpszClassName = "Template";

 // attempt to register -- exit if we can't
 if ( !RegisterClass ( &wndclass ) )
 return 0;
 }

 // create a window based on the class we just registered
 hwnd = CreateWindow (
 "Template" // class name
 , pszTitle // window caption (title)
 , WS_OVERLAPPEDWINDOW // style
 , CW_USEDEFAULT // initial x
 , CW_USEDEFAULT // initial y
 , CW_USEDEFAULT // initial cx
 , CW_USEDEFAULT // initial cy
 , 0 // no parent
 , 0 // no menu
 , hInstance // instance handle
 , NULL ); // no create parameters

 if ( hwnd == 0 )
 return 0;

 // show the window and force it to paint
 ShowWindow ( hwnd, nCmdShow );
 UpdateWindow ( hwnd );

 // enter the event loop -- remain in loop until window closes
 while ( GetMessage ( &msg, NULL, 0, 0 ) != FALSE )
 {
 DispatchMessage ( &msg );
 }

 return msg.wParam;
}

//**********************************************************
LRESULT CALLBACK WndProc ( HWND hwnd, UINT iMsg
 , WPARAM wParam, LPARAM lParam )
{

 switch ( iMsg )
 {
 case WM_DESTROY:
 PostQuitMessage (0);
 return 0;

 case WM_COMMAND:
 {
 switch ( LOWORD ( wParam ) )
 {
 case IDM_CHOOSE:
 {
 MessageBox ( hwnd, "Click on any window"
 , "Choose a window"
 , MB_OK | MB_ICONINFORMATION );

 SetCapture ( hwnd );
 }
 break;
 }
 }
 return 0;

 case WM_LBUTTONUP:
 {
 if ( GetCapture () == hwnd )
 {
 POINT pt;

 // retrieve the mouse coordinates
 pt.x = (short)LOWORD ( lParam );
 pt.y = (short)HIWORD ( lParam );

 // convert to screen units
 ClientToScreen ( hwnd, &pt );

 // determine handle of window under the click
 HWND hwndClick = WindowFromPoint ( pt );

 // display the window's text
 if ( hwndClick != 0 )
 {
 char szText[255];

 GetWindowText ( hwndClick, szText
 , sizeof szText );

 MessageBox ( hwnd, szText, "You clicked on"
 , MB_OK | MB_ICONINFORMATION );
 }

 // release the mouse capture
 ReleaseCapture ();
 }
 }

 case WM_PAINT:
 {
 PAINTSTRUCT ps;

 BeginPaint ( hwnd, &ps );

 RECT rc;

 GetClientRect ( hwnd, &rc );

 DrawText ( ps.hdc
 , "Select \"Choose Window\" from the menu"
 , -1, &rc
 , DT_SINGLELINE | DT_CENTER | DT_VCENTER );

 EndPaint ( hwnd, &ps );
 }
 return 0;

 default:
 return DefWindowProc ( hwnd, iMsg, wParam, lParam);
 }
}