我需要定期发出信号。定时器执行某些功能,发出我想要的信号。由于某种原因,没有发出此功能。我能够在最小代码上重现错误(参见下文)。如果我在没有计时器的情况下做同样的事情一切正常:
from threading import Timer
import time
from PySide import QtCore
class testSignals(QtCore.QObject):
signal = QtCore.Signal();
def __init__(self):
QtCore.QObject.__init__(self)
def run(self):
self.signal.emit()
class testConnection():
@QtCore.Slot()
def receiveMe(self):
print('Signal received')
# signal is emmited when data is changed
def __init__(self):
test = testSignals()
test.signal.connect(self.receiveMe)
test.run();
test = testConnection()
我能够在以下代码中重现我的问题:
from threading import Timer
import time
from PySide import QtCore
class testSignals(QtCore.QObject):
signal = QtCore.Signal();
def __init__(self):
self.is_running = False
QtCore.QObject.__init__(self)
self.start()
def emitMe(self):
self.is_running = False
self.start()
# print("emitMe")
self.signal.emit()
def start(self):
if not self.is_running:
self._timer = Timer(0.2, self.emitMe)
self._timer.start()
self.is_running = True
def stop(self):
self._timer.cancel()
self.is_running = False
class testConnection():
@QtCore.Slot()
def receiveMe(self):
print('Signal received')
# signal is emmited when data is changed
def __init__(self):
test = testSignals()
test.signal.connect(self.receiveMe)
test.start();
time.sleep(2.0)
test.stop();
test = testConnection()
短语“已接收信号”未在屏幕上打印。
答案 0 :(得分:2)
正如@ekhumoro在评论中所说,QTimer帮助了很多。我需要一个事件循环。我发布代码以使答案有效。我用QTimer重写了它,这使得一切都变得更加简单。请注意,我需要调用QCoreApplication来运行线程。同样,这只是重现我需要做的最小代码。
import time
from PySide import QtCore
from probeConnection import ProbeConnection
class testSignals(QtCore.QObject):
def __init__(self):
self.timer = QtCore.QTimer()
self.timer.timeout.connect(self.tick)
self.start()
def tick(self):
print("tick")
def getData(self):
return time.strftime('%H:%M:%S')
def start(self):
self.timer.start(1000)
def stop(self):
self.timer.stop()
class testConnection():
def receiveMe(self):
print('time: ' + self.test.getData())
def __init__(self):
self.test = testSignals()
self.test.timer.timeout.connect(self.receiveMe)
app = QtCore.QCoreApplication([])
test = testConnection()
timer = QtCore.QTimer()
timer.singleShot(4000,app.exit)
app.exec_()
它产生:
tick
time: 13:23:37
tick
time: 13:23:38
tick
time: 13:23:39
tick
time: 13:23:40