python - "WindowsError: access violation 000001" on DispatchMessageW in EventLoop -

i research python internals , write gui generic windows use windows api.

# -*- coding: utf-8 -*-  import time import threading import logging import uuid  import ctypes import ctypes.wintypes  import const   int = ctypes.wintypes.c_int lpvoid = ctypes.wintypes.c_void_p hcursor = ctypes.wintypes.handle lresult = ctypes.wintypes.lparam colorref = ctypes.wintypes.dword pvoid = ctypes.wintypes.c_void_p wchar = ctypes.wintypes.c_wchar bchar = ctypes.wintypes.c_wchar lprect = ctypes.wintypes.pointer(ctypes.wintypes.rect) lppoint = ctypes.wintypes.pointer(ctypes.wintypes.point) lpmsg = ctypes.wintypes.pointer(ctypes.wintypes.msg) uint_ptr = ctypes.wintypes.handle long_ptr = ctypes.wintypes.handle   #wndproc = ctypes.wintypes.winfunctype(ctypes.c_long, ctypes.wintypes.hwnd, ctypes.wintypes.uint, ctypes.wintypes.wparam, ctypes.wintypes.lparam) wndproc = ctypes.wintypes.winfunctype(ctypes.c_int, ctypes.c_int, ctypes.c_int, ctypes.c_int, ctypes.c_int)   sw_shownormal = 1 sw_show = 5  cs_hredraw = 2 cs_vredraw = 1  cw_usedefault = 0x80000000  wm_destroy = 2   class wndclassex(ctypes.wintypes.structure):     _fields_ = [("cbsize", ctypes.wintypes.uint),                 ("style", ctypes.wintypes.uint),                 ("lpfnwndproc", wndproc),                 ("cbclsextra", ctypes.wintypes.int),                 ("cbwndextra", ctypes.wintypes.int),                 ("hinstance", ctypes.wintypes.handle),                 ("hicon", ctypes.wintypes.handle),                 ("hcursor", ctypes.wintypes.handle),                 ("hbrush", ctypes.wintypes.handle),                 ("lpszmenuname", ctypes.wintypes.lpcwstr),                 ("lpszclassname", ctypes.wintypes.lpcwstr),                 ("hiconsm", ctypes.wintypes.handle)]   class window(object):     def __init__(self, app, wclassname=none, wname=u"custom title"):         self.__app = app         #         self.__log = logging.getlogger("win_ui.window")         #         self.__hinst = app.getinstance()         self.__hwnd = none         #         if wclassname none:             wclassname = u"newwindowclass-{uid}".format(uid=uuid.uuid4().hex)         #         self.__wclassname = wclassname         self.__wname = wname         #         #self.__event_dispatcher = eventdispatcher(app=app)         #self.__event_dispatcher.start()         #         self.__has_exit = threading.condition()         #         self._create()      def wnd_proc(self, hwnd, msg, wparam, lparam):         self.__log.debug("wndproc: hwnd={hwnd!r}, msg={msg!r}, wparam={wparam!r}, lparam={lparam!r}".format(hwnd=hwnd, msg=msg, wparam=wparam, lparam=lparam))         #self.__event_dispatcher.push((hwnd, msg, wparam, lparam))         #         result = none          #         self.__has_exit.acquire()         self.__has_exit.wait(0.1)         #         if msg == wm_destroy:             self.__app.loadlibrary("user32").postquitmessage(0)             result = 0         #         if result none:             result = self.__app.loadlibrary("user32").defwindowprocw(hwnd, msg, wparam, lparam)         #         self.__has_exit.release()         #         return result       def _create(self):         wndproc = wndproc(self.wnd_proc)          hbrush = self.__app.loadlibrary("gdi32").getstockobject(const.ltgray_brush)         print hbrush          wndclass = wndclassex()         wndclass.cbsize = ctypes.sizeof(wndclassex)         wndclass.style = cs_hredraw | cs_vredraw         wndclass.lpfnwndproc = wndproc         wndclass.cbclsextra = 0         wndclass.cbwndextra = 0         wndclass.hinstance = self.__hinst         wndclass.hicon = 0 #self.__app.loadicon()         wndclass.hcursor = 0 #self.__app.loadcursor()         wndclass.hbrush = hbrush         wndclass.lpszmenuname = none         wndclass.lpszclassname = ctypes.c_wchar_p(self.__wclassname)         wndclass.hiconsm = 0 #self.__app.loadcursor()          self.__log.debug("wndclass.cbsize = {cbsize!r}".format(cbsize=wndclass.cbsize))         self.__log.debug("wndclass.lpfnwndproc = {lpfnwndproc!r}".format(lpfnwndproc=wndclass.lpfnwndproc))         self.__log.debug("wndclass.hinstance = {hinst!r}".format(hinst=wndclass.hinstance))         self.__log.debug("wndclass.lpszclassname = {lpszclassname!r}".format(lpszclassname=wndclass.lpszclassname))          result = self.__app.loadlibrary("user32").registerclassexw(ctypes.byref(wndclass))         self.__log.debug("0x0{result:x} = registerclassexw(...)".format(result=result))          #         self.__x = cw_usedefault         self.__y = cw_usedefault         self.__width = 300         self.__height = 300         #         exstyle = 0         #exstyle = const.ws_ex_appwindow         style = const.ws_overlappedwindow         #style = const.ws_overlappedwindow | const.ws_caption | const.ws_visible         wclassname = ctypes.c_wchar_p(self.__wclassname)         wname = ctypes.c_wchar_p(self.__wname)         print wname         #         self.__app.loadlibrary("user32").createwindowexw.restype = ctypes.wintypes.hwnd         self.__app.loadlibrary("user32").createwindowexw.argtypes = [ctypes.wintypes.dword, ctypes.c_wchar_p, ctypes.c_wchar_p, ctypes.wintypes.dword, ctypes.c_int, ctypes.c_int, ctypes.c_int, ctypes.c_int, ctypes.wintypes.hwnd, ctypes.wintypes.hmenu, ctypes.wintypes.hinstance, ctypes.wintypes.lpvoid]         #         self.__hwnd = self.__app.loadlibrary("user32").createwindowexw(exstyle, wclassname, wname, style, self.__x, self.__y, self.__width, self.__height, 0, none, self.__hinst, 0)         self.__log.debug("0x0{hwnd!r} = createwindowexw(...)".format(hwnd=self.__hwnd))         if not self.__hwnd:             print self.__app.getlasterror()             raise windowserror("failed create window")          self.__log.debug("showwindow(hwnd=0x{hwnd:x})".format(hwnd=self.__hwnd))         result = self.__app.loadlibrary("user32").showwindow(self.__hwnd, sw_show)         self.__log.debug('0x0{result:x} = showwindow(...)'.format(result=result))          self.__log.debug('updatewindow(hwnd=0x{hwnd:x})'.format(hwnd=self.__hwnd))         result = self.__app.loadlibrary("user32").updatewindow(self.__hwnd)         self.__log.debug('0x0{result:x} = updatewindow(...)'.format(result=result)) 

gui generic window create cause exception "widnowserror: access violation 000001" on dispatchmessagew in eventloop.

# -*- coding: utf-8 -*-  import logging import uuid  import ctypes import ctypes.wintypes  import const   class application(object):     def __init__(self):         self.__log = logging.getlogger("win_ui.application")         self.__libs = {}         #         self._event_thread = self.loadlibrary("kernel32").getcurrentthreadid()      def loadlibrary(self, name):         if name in self.__libs:             result = self.__libs[name]         else:             module = getattr(ctypes.windll, name)             result = self.__libs[name] = module         return result      def getinstance(self, hmodule=none):         self.__log.debug('getmodulehandlew(hmodule={hmodule!r})'.format(hmodule=hmodule))         result = self.loadlibrary("kernel32").getmodulehandlew(none)         self.__log.debug('0x0{result:x} = getmodulehandlew(...)'.format(result=result))         return result      def loadicon(self, iconname=none):         if iconname none:             iconname = const.idi_application         hinst = self.getinstance()         result = self.loadlibrary("user32").loadiconw(hinst, iconname)         return result      def loadcursor(self, v=none):         if v none:             v = const.idi_application         hinst = self.getinstance()         result = self.loadlibrary("user32").loadcursorw(hinst, v)         return result      def getlasterror(self):         self.__log.debug('getlasterror()')         result = self.loadlibrary("kernel32").getlasterror()         #print result         #rs = self.loadlibrary("kernel32").formatmessagew(result)         #print rs         self.__log.debug('0x0{result:x} = getlasterror()'.format(result=result))         return result      def check(self):         if self._event_thread != self.loadlibrary("kernel32").getcurrentthreadid():             raise runtimeerror("thread?")      def run(self):         self.check()          msg = ctypes.wintypes.msg()         lpmsg = ctypes.pointer(msg)          self.__log.debug('entering message loop')         #         user32 = self.loadlibrary("user32")         while user32.getmessagew(lpmsg, 0, 0, 0) != 0:         #while self.loadlibrary("user32").peekmessagew(ctypes.byref(msg), 0, 0, 0, const.pm_remove):             user32.translatemessage(lpmsg)             print lpmsg             user32.dispatchmessagew(lpmsg)         #         self.__log.debug('done.') 

when refactoring , calls registerwindowex , createwindowex on separate python method createwindowex start return 0x0 , getlasterror retrun 0x0. problem there?