pip?install?PyQt5

#?It?imports?all?the?classes,?methods,?and?attributes?of?the?`PyQt5.QtWidgets`?module.
from?PyQt5.QtWidgets?import?*

#?It?imports?all?the?classes,?methods,?and?attributes?of?the?`PyQt5.QtCore`?module.
from?PyQt5.QtCore?import?*

#?It?imports?all?the?classes,?methods,?and?attributes?of?the?`PyQt5.QtGui`?module.
from?PyQt5.QtGui?import?*

#?It?imports?the?`sys`?module.
import?sys

#?It?imports?the?`time`?module?and?it?renames?it?to?`t`.
import?time?as?t

#?This?class?is?a?widget?that?displays?a?progress?bar.
class?ProgressBarUI(QWidget):
????def?__init__(self):
????????super(ProgressBarUI,?self).__init__()
????????self.init_ui()

????def?init_ui(self):
????????"""
????????This?function?initializes?the?UI.
????????"""
????????self.setWindowTitle('PyQt5進(jìn)度條案例?公眾號(hào)：Python 集中營')
????????self.setWindowIcon(QIcon('prop.png'))
????????self.resize(500,?200)

????????self.progressBar?=?QProgressBar()
????????self.progressBar.setValue(0)
????????self.progressBar.setAlignment(Qt.AlignCenter)

????????hbox?=?QHBoxLayout()
????????hbox.addWidget(self.progressBar)

????????self.timer?=?QTimer()
????????self.timer.timeout.connect(self.listen_step)
????????self.timer.start(100)

????????self.step?=?0

????????self.thread_?=?WorkThread()
????????self.thread_.thread_step.connect(self.step_add)

????????self.thread_.start()

????????self.setLayout(hbox)

????def?step_add(self,?n):
????????"""
????????It?adds?n?to?the?current?value?of?the?counter

????????:param?n:?the?number?of?steps?to?take
????????"""
????????self.step?=?self.step?+?n

????def?listen_step(self):
????????"""
????????>?The?function?`listen_step`?is?called?by?the?`listen`?function,?and?it?returns?the?next?step?in?the?conversation
????????"""
????????if?self.progressBar.value()?>=?100:
????????????self.timer.stop()
????????else:
????????????self.progressBar.setValue(self.step)

#?This?class?is?a?subclass?of?QThread?and?it's?used?to?create?a?thread?that?will?run?the?function?that?will?be?passed?to
#?it
class?WorkThread(QThread):
????#?A?signal?that?is?emitted?when?the?value?of?the?counter?changes.
????thread_step?=?pyqtSignal(int)

????def?__init__(self):
????????"""
????????A?constructor.?It?is?called?when?an?object?is?created?from?a?class?and?it?allows?the?class?to?initialize?the
????????attributes?of?a?class.
????????"""
????????super(WorkThread,?self).__init__()
????????self.working?=?True

????def?__del__(self):
????????"""
????????A?destructor.?It?is?called?when?the?object?is?destroyed.
????????"""
????????self.working?=?False

????def?run(self):
????????for?n?in?range(1,?101):
????????????self.thread_step.emit(1)
????????????t.sleep(0.1)

#?A?common?idiom?to?use?this?as?the?last?statement?in?a?module?(a?file?that?contains?Python?code).
if?__name__?==?'__main__':
????app?=?QApplication(sys.argv)
????main?=?ProgressBarUI()
????main.show()
????sys.exit(app.exec_())