Source code for taurus.qt.qtcore.util.signal

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# This file is part of Taurus
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# http://taurus-scada.org
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# Copyright 2011 CELLS / ALBA Synchrotron, Bellaterra, Spain
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# Taurus is free software: you can redistribute it and/or modify
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"""Provide a Signal class for non-QObject objects"""
from __future__ import print_function

from builtins import object

from taurus.external.qt import Qt
from threading import Lock
from weakref import WeakKeyDictionary

__all__ = ['baseSignal']


[docs]def baseSignal(name, *args): """Signal class for non-Qobject objects. :param name: signal name (unlike pyqtSignal, name has to be specified explicitely) :param args: arguments passed to the pyqtSignal """ main_lock = Lock() lock_dict = WeakKeyDictionary() classname = name.capitalize() + "Signaller" attrs = {name: Qt.pyqtSignal(*args, name=name)} signaller_type = type(classname, (Qt.QObject,), attrs) def get_lock(self): with main_lock: if self not in lock_dict: lock_dict[self] = Lock() return lock_dict[self] def get_signaller(self): with get_lock(self): if not hasattr(self, '_signallers'): self._signallers = {} if (name, args) not in self._signallers: self._signallers[name, args] = signaller_type() return self._signallers[name, args] def get_signal(self): return getattr(get_signaller(self), name) doc = "Base signal {}".format(name) return property(get_signal, doc=doc)
if __name__ == '__main__': class Base(object): test = baseSignal('test', int) def print_func(arg): print(arg) base1, base2 = Base(), Base() base1.test.connect(print_func) base2.test.connect(print_func) base1.test.emit(1) base2.test.emit(2)