问题
So , I am trying to blink the push button with the color that I pass and between white. And it only seems to blink it so many times after that code would crash. I have tried it to implement the blinking with different blink rates and it would it still break at some time.
- in 'a' I have the string like "Background-color: rgb(255,0,0)".
- in 'timings' i have a list like[208, 280]or it could be [48,32,48,32,100,280], this represents the on and off timings 'zeroth index' represents on and 'index 1' represents off time and follows the pattern so on.
while True:
i = 0
while i < len(timings):
if self.p[2] == 1:
self.b.setStyleSheet("{}".format(a))
self.b.update()
time.sleep(timings[i]/1000)
self.b.setStyleSheet("Background-color: rgb(255,255,255)")
self.b.update()
time.sleep(timings[i+1]/1000)
i = i + 2
self.head1, self.head2, self.head3 all have list with some thing like this ["Background-color:rgb(255,0,0)",list of on and off patterns, head number#]
right now, I am working with three heads.
def flash(self):
obj1 = threads(self.head1, self.head1_pb)
obj2 = threads(self.head2, self.head2_pb)
obj3 = threads(self.head3, self.head3_pb)
obj1.start()
time.sleep(.02)
obj2.start()
time.sleep(.02)
obj3.start()
class threads(Thread):
def __init__(self, a, pb):
Thread.__init__(self)
self.p = a
self.b = pb
def run(self):
a = self.p[0]
timings = self.p[1]
print(timings[0])
while True:
i = 0
while i < len(timings):
if self.p[2] == 1:
self.b.setStyleSheet("{}".format(a))
self.b.update()
time.sleep(timings[i]/1000)
self.b.setStyleSheet("Background-color: rgb(255,255,255)")
self.b.update()
time.sleep(timings[i+1]/1000)
i = i + 2
elif self.p[2] == 2:
self.b.setStyleSheet("{}".format(a))
self.b.update()
time.sleep(timings[i]/1000)
self.b.setStyleSheet("Background-color: rgb(255,255,255)")
self.b.update()
time.sleep(timings[i+1]/1000)
i = i + 2
else:
self.b.setStyleSheet("{}".format(a))
self.b.update()
time.sleep(timings[i]/1000)
self.b.setStyleSheet("Background-color: rgb(255,255,255)")
self.b.update()
time.sleep(timings[i+1]/1000)
i = i + 2
回答1:
You can change the color as many times as you want, the problem is that you should not use a time consuming loop or use time.sleep() because they block the eventloop generating the GUI to freeze. Instead, use a QTimer to call the task that changes color every so often.
In the following example, create a custom button that implements what you want:
from PySide2 import QtCore, QtGui, QtWidgets
class PushButton(QtWidgets.QPushButton):
def __init__(self, *args, **kwargs):
super(PushButton, self).__init__(*args, **kwargs)
self._color = QtGui.QColor("white")
timer_on = QtCore.QTimer(singleShot=True, timeout=self.on_timeout)
timer_off = QtCore.QTimer(singleShot=True, timeout=self.on_timeout)
self._timers = (timer_on, timer_off)
for timer, function in zip(self._timers, (self.on, self.off)):
timer.timeout.connect(function)
def setTime(self, on_time, off_time):
for t, timer in zip((on_time, off_time), self._timers):
timer.setInterval(t)
@QtCore.Slot()
def on_timeout(self):
timer = self.sender()
if timer not in self._timers:
return
timer_on, timer_off = self._timers
another_timer = timer_off if timer is timer_on else timer_on
another_timer.start()
def start(self):
timer_on, _ = self._timers
timer_on.start()
def stop(self):
for timer in self._timers:
timer.stop()
self.off()
def color(self):
return self._color
def setColor(self, color):
if self.color() == color:
return
self._color = color
def on(self):
self.setStyleSheet(
"""PushButton{ background-color: %s}""" % (self.color().name(),)
)
def off(self):
self.setStyleSheet(
"""PushButton{ background-color: rgb(255,255,255)}"""
)
class Widget(QtWidgets.QWidget):
def __init__(self, parent=None):
super(Widget, self).__init__(parent)
button = PushButton()
button.setColor(QtGui.QColor("salmon"))
button.setTime(208, 280)
button.start()
# stop blink in 30 seconds
# QtCore.QTimer.singleShot(30 * 1000, button.stop)
lay = QtWidgets.QVBoxLayout(self)
lay.addWidget(button)
if __name__ == "__main__":
import sys
app = QtWidgets.QApplication(sys.argv)
app.setStyle("fusion")
w = Widget()
w.show()
sys.exit(app.exec_())
Plus:
As you note that you have a lot of data, it is best to create an iterator to save memory. Considering the above I have created a QPushButton that obtains the data from the iterator.
import random
from functools import partial
from PySide2 import QtCore, QtGui, QtWidgets
def generate_data():
i = 0
while i < 1000000:
color_on = random.randint(10, 500)
color_off = random.randint(10, 500)
color = QtGui.QColor(*random.sample(range(255), 3))
yield color_on, color_off, color
i += 1
class PushButton(QtWidgets.QPushButton):
def __init__(self, *args, **kwargs):
super(PushButton, self).__init__(*args, **kwargs)
self._color = QtGui.QColor("white")
self._generator = None
self.m_timer = QtCore.QTimer(
self, timeout=self.on_timeout, singleShot=True
)
def setGenerator(self, generator):
self._generator = generator
def start(self):
self.on_timeout()
@QtCore.Slot()
def on_timeout(self):
try:
time_on, time_off, color = next(self._generator)
self.setColor(color)
self.m_timer.start(time_on + time_off)
QtCore.QTimer.singleShot(
time_on, partial(self.setColor, QtGui.QColor("white"))
)
except StopIteration:
self.m_timer.stop()
def setColor(self, color):
self.setStyleSheet(
"""PushButton{ background-color: %s}""" % (color.name(),)
)
class Widget(QtWidgets.QWidget):
def __init__(self, parent=None):
super(Widget, self).__init__(parent)
lay = QtWidgets.QVBoxLayout(self)
for _ in range(6):
button = PushButton()
button.setGenerator(generate_data())
button.start()
lay.addWidget(button)
if __name__ == "__main__":
import sys
app = QtWidgets.QApplication(sys.argv)
app.setStyle("fusion")
w = Widget()
w.resize(320, 240)
w.show()
sys.exit(app.exec_())
来源：https://stackoverflow.com/questions/56774100/how-many-times-the-most-i-can-change-the-background-of-the-pushbutton