class Listener(ListenerMixin, _base.Listener):
#: The Windows hook ID for low level keyboard events, ``WH_KEYBOARD_LL``
_EVENTS = 13
_WM_INPUTLANGCHANGE = 0x0051
_WM_KEYDOWN = 0x0100
_WM_KEYUP = 0x0101
_WM_SYSKEYDOWN = 0x0104
_WM_SYSKEYUP = 0x0105
# A bit flag attached to messages indicating that the payload is an actual
# UTF-16 character code
_UTF16_FLAG = 0x1000
# A special virtual key code designating unicode characters
_VK_PACKET = 0xE7
#: The messages that correspond to a key press
_PRESS_MESSAGES = (_WM_KEYDOWN, _WM_SYSKEYDOWN)
#: The messages that correspond to a key release
_RELEASE_MESSAGES = (_WM_KEYUP, _WM_SYSKEYUP)
#: Additional window messages to propagate to the subclass handler.
_WM_NOTIFICATIONS = (_WM_INPUTLANGCHANGE, )
#: A mapping from keysym to special key
_SPECIAL_KEYS = {key.value.vk: key for key in Key}
_HANDLED_EXCEPTIONS = (SystemHook.SuppressException, )
class _KBDLLHOOKSTRUCT(ctypes.Structure):
"""Contains information about a mouse event passed to a
``WH_KEYBOARD_LL`` hook procedure, ``LowLevelKeyboardProc``.
"""
_fields_ = [('vkCode', wintypes.DWORD), ('scanCode', wintypes.DWORD),
('flags', wintypes.DWORD), ('time', wintypes.DWORD),
('dwExtraInfo', ctypes.c_void_p)]
#: A pointer to a :class:`KBDLLHOOKSTRUCT`
_LPKBDLLHOOKSTRUCT = ctypes.POINTER(_KBDLLHOOKSTRUCT)
def __init__(self, *args, **kwargs):
super(Listener, self).__init__(*args, **kwargs)
self._translator = KeyTranslator()
self._event_filter = self._options.get('event_filter',
lambda msg, data: True)
def _convert(self, code, msg, lpdata):
if code != SystemHook.HC_ACTION:
return
data = ctypes.cast(lpdata, self._LPKBDLLHOOKSTRUCT).contents
is_packet = data.vkCode == self._VK_PACKET
# Suppress further propagation of the event if it is filtered
if self._event_filter(msg, data) is False:
return None
elif is_packet:
return (msg | self._UTF16_FLAG, data.scanCode)
else:
return (msg, data.vkCode)
@AbstractListener._emitter
def _process(self, wparam, lparam):
msg = wparam
vk = lparam
# If the key has the UTF-16 flag, we treat it as a unicode character,
# otherwise convert the event to a KeyCode; this may fail, and in that
# case we pass None
is_utf16 = msg & self._UTF16_FLAG
if is_utf16:
msg = msg ^ self._UTF16_FLAG
scan = vk
key = KeyCode.from_char(six.unichr(scan))
else:
try:
key = self._event_to_key(msg, vk)
except OSError:
key = None
if msg in self._PRESS_MESSAGES:
self.on_press(key)
elif msg in self._RELEASE_MESSAGES:
self.on_release(key)
# pylint: disable=R0201
@contextlib.contextmanager
def _receive(self):
"""An empty context manager; we do not need to fake keyboard events.
"""
yield
# pylint: enable=R0201
def _on_notification(self, code, wparam, lparam):
"""Receives ``WM_INPUTLANGCHANGE`` and updates the cached layout.
"""
if code == self._WM_INPUTLANGCHANGE:
self._translator.update_layout()
def _event_to_key(self, msg, vk):
"""Converts an :class:`_KBDLLHOOKSTRUCT` to a :class:`KeyCode`.
:param msg: The message received.
:param vk: The virtual key code to convert.
:return: a :class:`pynput.keyboard.KeyCode`
:raises OSError: if the message and data could not be converted
"""
# If the virtual key code corresponds to a Key value, we prefer that
if vk in self._SPECIAL_KEYS:
return self._SPECIAL_KEYS[vk]
else:
return KeyCode(**self._translate(vk, msg in self._PRESS_MESSAGES))
def _translate(self, vk, is_press):
"""Translates a virtual key code to a parameter list passable to
:class:`pynput.keyboard.KeyCode`.
:param int vk: The virtual key code.
:param bool is_press: Whether this is a press event.
:return: a parameter list to the :class:`pynput.keyboard.KeyCode`
constructor
"""
return self._translator(vk, is_press)
def canonical(self, key):
# If the key has a scan code, and we can find the character for it,
# return that, otherwise call the super class
scan = getattr(key, '_scan', None)
if scan is not None:
char = self._translator.char_from_scan(scan)
if char is not None:
return KeyCode.from_char(char)
return super(Listener, self).canonical(key)
def __init__(self, *args, **kwargs):
super(Listener, self).__init__(*args, **kwargs)
self._translator = KeyTranslator()
self._event_filter = self._options.get(
'event_filter',
lambda msg, data: True)
def __init__(self, *args, **kwargs):
super(Listener, self).__init__(*args, **kwargs)
self._translator = KeyTranslator()