LRESULT CALLBACK WndProc(HWND hwnd, UINT msg, WPARAM wParam, LPARAM lParam)
{
	static HWND hChild;
	static RECT rect;
	switch(msg)
	{
		case WM_CREATE:{
			printf("wm_create executed\n");
			GetClientRect(hwnd, &rect);

			WNDCLASSEX wcc; //child windowclassex
			memset(&wcc, 0, sizeof(WNDCLASSEX));
			wcc.cbSize = sizeof(WNDCLASSEX);
			wcc.style = CS_HREDRAW | CS_VREDRAW;
			wcc.hInstance = GetModuleHandle(NULL);
			wcc.hbrBackground = (HBRUSH)COLOR_APPWORKSPACE;
			wcc.lpfnWndProc = ChildProc;
			wcc.lpszClassName = "SubClass";
			if(!RegisterClassEx(&wcc)){MessageBox(hwnd, "Register Child Class Failed", "ERROR",MB_ICONEXCLAMATION | MB_OK);}
			hChild = CreateWindowEx(
				WS_EX_DLGMODALFRAME,
				wcc.lpszClassName,
				"",
				WS_CHILD | WS_VISIBLE | WS_TILED,
				20, 90, 50, 50, //x y xW yW
				hwnd,
				NULL,
				GetModuleHandle(NULL),
				NULL);
			if(hChild==NULL)printf("Child Create failed!\n");
			return 0;}
		case WM_SIZE:{
			rect.right = LOWORD(lParam);
			rect.bottom = HIWORD(lParam);
			MoveWindow(hChild, 5, rect.bottom - 35, rect.right - 10, 30, TRUE);
			return 0;}
		case WM_CLOSE: DestroyWindow(hwnd);break;
		case WM_DESTROY: PostQuitMessage(0);break;
/*		case WM_LBUTTONUP: 
		{
			char szFileName[MAX_PATH];
			HINSTANCE hInstance = GetModuleHandle(NULL);

			GetModuleFileName(hInstance, szFileName, MAX_PATH);
			MessageBox(hwnd , szFileName, "This program is:", MB_ICONINFORMATION| MB_OK | MB_ICONINFORMATION);
		}break; */
		default:
		return DefWindowProc(hwnd, msg, wParam, lParam);
	}
	return 0;
}