def disconnect(signal: pyqtSignal, callback: Callable):
"""
After using ``connect()`` to link a signal, use this function to disconnect from the given signal.
This function will also work if the ``callback`` was connected directly with ``signal.connect()``.
:param signal: the signal to ``disconnect()`` from.
:param callback: the callback to connect (will be called after ``signal.emit(...)``.
"""
if hasattr(callback, 'tb_wrapper'):
disconnectable = callback.tb_wrapper
elif hasattr(callback, "__self__") and hasattr(callback, "__func__"):
disconnectable = callback.__self__.tb_mapping[callback.__func__.__name__]
else:
disconnectable = callback
signal.disconnect(disconnectable)
def is_connected(signal: pyqtSignal, slot: pyqtSlot) -> bool:
"""
Determine if a (bound) signal is connected to a slot.
:param signal: signal (a return value from a call to pyqtSignal(...))
:param slot: slot (a method on a QObject, decorated with pyqtSlot)
:return: True if connected, False otherwise
"""
try:
signal.connect(slot, Qt.UniqueConnection)
except TypeError as exc:
assert str(exc) in (
'connection is not unique',
'connect() failed between MyObj.sig_test[] and meth()')
return True
else:
signal.disconnect(slot)
return False
def disconnect_lambda_slots(*, signal: pyqtSignal) -> None:
# ignore first run - when no slots connected
with contextlib.suppress(TypeError):
signal.disconnect()
