Develop Reference

How to stop a thread using a button

We are creating an object detection project using Object detection API. We are train the program making pyqt5 GUI application. Trying to run the training part using thread. We want to stop the running thread using a push button. Here the code sample
class stopClass(QtCore.QThread):
def __init__(self, parent=None):
super(stopClass, self).__init__(parent)
def startTrain(self):
#changing directory
os.chdir(r"c://tensorflow_1//models//research//object_detection")
args3 = shlex.split('python train.py --logtostderr --train_dir=training/ --
pipeline_config_path=training/faster_rcnn_inception_v2_pets.config')
subprocess.run(args3, shell = True)
return
def run(self):
self.startTrain()
class Ui_MainWindow(object):
def setupUi(self, MainWindow):
MainWindow.setObjectName("MainWindow")
MainWindow.resize(701, 495)
self.centralwidget = QtWidgets.QWidget(MainWindow)
self.centralwidget.setObjectName("centralwidget")
self.Annotation = QtWidgets.QPushButton(self.centralwidget)
self.Annotation.setGeometry(QtCore.QRect(480, 10, 181, 41))
self.Annotation.setToolTip("")
self.Annotation.setObjectName("Annotation")
self.Start_train = QtWidgets.QPushButton(self.centralwidget)
self.Start_train.setGeometry(QtCore.QRect(480, 110, 181, 41))
self.Start_train.setObjectName("Start_train")
self.Stop_train = QtWidgets.QPushButton(self.centralwidget)
self.Stop_train.setEnabled(False)
self.Stop_train.setGeometry(QtCore.QRect(480, 160, 181, 41))
self.Stop_train.setObjectName("Stop_train")
MainWindow.setCentralWidget(self.centralwidget)
self.menubar = QtWidgets.QMenuBar(MainWindow)
self.menubar.setGeometry(QtCore.QRect(0, 0, 701, 21))
self.menubar.setObjectName("menubar")
MainWindow.setMenuBar(self.menubar)
self.statusbar = QtWidgets.QStatusBar(MainWindow)
self.statusbar.setObjectName("statusbar")
MainWindow.setStatusBar(self.statusbar)
self.retranslateUi(MainWindow)
QtCore.QMetaObject.connectSlotsByName(MainWindow)
self.Start_train.clicked.connect(self.starting)
def retranslateUi(self, MainWindow):
_translate = QtCore.QCoreApplication.translate
MainWindow.setWindowTitle(_translate("MainWindow", "MainWindow"))
self.Start_train.setText(_translate("MainWindow", "start train"))
self.Stop_train.setText(_translate("MainWindow", "stop train"))
def starting(self):
self.stopThread = stopClass()
self.stopThread.start()
self.Stop_train.setEnabled(True)
self.Stop_train.clicked.connect(self.stopThread.exit)
self.Start_train.setEnabled(False)

In this case I do not see the need to use threads since it is enough to use QProcess that allows a simple handling of the execution of the script. On the other hand, do not modify the script generated by pyuic so my solution assumes that you must recreate that script that must be called gui.py:
import shlex
import sys
from PyQt5.QtCore import QObject, QProcess
from PyQt5.QtWidgets import QApplication, QMainWindow
from gui import Ui_MainWindow
class Manager(QObject):
def __init__(self, parent=None):
super().__init__(parent)
self._process = QProcess()
working_directory = r"c://tensorflow_1//models//research//object_detection"
self.process.setWorkingDirectory(working_directory)
self.process.setProgram(sys.executable)
args = shlex.split(
"train.py --logtostderr --train_dir=training/ --pipeline_config_path=training/faster_rcnn_inception_v2_pets.config"
)
self.process.setArguments(args)
#property
def process(self):
return self._process
def start(self):
if self.process.state() == QProcess.NotRunning:
self.process.start()
def stop(self):
if self.process.state() != QProcess.NotRunning:
self.process.kill()
class MainWindow(QMainWindow, Ui_MainWindow):
def __init__(self, parent=None):
super().__init__(parent)
self.setupUi(self)
self.manager = Manager()
self.Start_train.clicked.connect(self.manager.start)
self.Stop_train.clicked.connect(self.manager.stop)
self.manager.process.stateChanged.connect(self._handle_stateChanged)
def _handle_stateChanged(self, state):
self.Start_train.setEnabled(state != QProcess.Running)
self.Stop_train.setEnabled(state == QProcess.Running)
def main():
app = QApplication(sys.argv)
w = MainWindow()
w.show()
sys.exit(app.exec_())
if __name__ == "__main__":
main()

pyqt5 closing a child window from a parent window

I have created 2 windows, win1 and win2, using qt designer and have added two buttons: btn_open_win2 to open win2 from win1 and btn_close to close win2.
When I run win2 directly the close method works correctly but when I run win1 and call win2 from it, the close button on win2 doesn't operate correctly.
I know that the problem arises from the point that win2 has been defined inside the if __name__ =='__main__' part as shown in the below codes but I can't solve this problem.
win1:
from PyQt5 import QtCore, QtGui, QtWidgets
from PyQt5.QtWidgets import QApplication, QMainWindow
class Ui_Win1(object):
def setupUi(self, MainWindow):
MainWindow.setObjectName("Win1")
MainWindow.resize(640, 480)
self.centralwidget = QtWidgets.QWidget(MainWindow)
self.centralwidget.setObjectName("centralwidget")
self.btn_open_win2 = QtWidgets.QPushButton(self.centralwidget)
self.btn_open_win2.setGeometry(QtCore.QRect(250, 170, 131, 101))
self.btn_open_win2.setObjectName("btn_open_win2")
self.btn_open_win2.clicked.connect(self.on_open_win2)
MainWindow.setCentralWidget(self.centralwidget)
self.statusbar = QtWidgets.QStatusBar(MainWindow)
self.statusbar.setObjectName("statusbar")
MainWindow.setStatusBar(self.statusbar)
self.retranslateUi(MainWindow)
QtCore.QMetaObject.connectSlotsByName(MainWindow)
def retranslateUi(self, MainWindow):
_translate = QtCore.QCoreApplication.translate
MainWindow.setWindowTitle(_translate("MainWindow", "Win1"))
self.btn_open_win2.setText(_translate("MainWindow", "open win2"))
def on_open_win2(self):
from win2 import Ui_Win2
self.win = QMainWindow()
self.ui = Ui_Win2()
self.ui.setupUi(self.win)
self.win.show()
if __name__ == '__main__':
import sys
app = QApplication(sys.argv)
win1 = QMainWindow()
ui = Ui_Win1()
ui.setupUi(win1)
win1.show()
sys.exit(app.exec_())
win2:
from PyQt5 import QtCore, QtGui, QtWidgets
from PyQt5.QtWidgets import QApplication, QMainWindow
class Ui_Win2(object):
def setupUi(self, MainWindow):
MainWindow.setObjectName("Win2")
MainWindow.resize(640, 480)
self.centralwidget = QtWidgets.QWidget(MainWindow)
self.centralwidget.setObjectName("centralwidget")
self.btn_close = QtWidgets.QPushButton(self.centralwidget)
self.btn_close.setGeometry(QtCore.QRect(260, 180, 131, 101))
self.btn_close.setObjectName("btn_close")
self.btn_close.clicked.connect(self.on_close)
MainWindow.setCentralWidget(self.centralwidget)
self.statusbar = QtWidgets.QStatusBar(MainWindow)
self.statusbar.setObjectName("statusbar")
MainWindow.setStatusBar(self.statusbar)
self.retranslateUi(MainWindow)
QtCore.QMetaObject.connectSlotsByName(MainWindow)
def retranslateUi(self, MainWindow):
_translate = QtCore.QCoreApplication.translate
MainWindow.setWindowTitle(_translate("MainWindow", "Win2"))
self.btn_close.setText(_translate("MainWindow", "close"))
def on_close(self):
# win2 = QMainWindow()
# ui = Ui_Win2()
# ui.setupUi(win2)
win2.close()
if __name__ == '__main__':
import sys
app = QApplication(sys.argv)
win2 = QMainWindow()
ui = Ui_Win2()
ui.setupUi(win2)
win2.show()
sys.exit(app.exec_())

change win2 like this:
from PyQt5 import QtCore, QtGui, QtWidgets
from PyQt5.QtWidgets import QApplication, QMainWindow
class Ui_Win2(object):
def setupUi(self, MainWindow):
self.MainWindow = MainWindow
MainWindow.setObjectName("Win2")
MainWindow.resize(640, 480)
self.centralwidget = QtWidgets.QWidget(MainWindow)
self.centralwidget.setObjectName("centralwidget")
self.btn_close = QtWidgets.QPushButton(self.centralwidget)
self.btn_close.setGeometry(QtCore.QRect(260, 180, 131, 101))
self.btn_close.setObjectName("btn_close")
self.btn_close.clicked.connect(self.on_close)
MainWindow.setCentralWidget(self.centralwidget)
self.statusbar = QtWidgets.QStatusBar(MainWindow)
self.statusbar.setObjectName("statusbar")
MainWindow.setStatusBar(self.statusbar)
self.retranslateUi(MainWindow)
QtCore.QMetaObject.connectSlotsByName(MainWindow)
def retranslateUi(self, MainWindow):
_translate = QtCore.QCoreApplication.translate
MainWindow.setWindowTitle(_translate("MainWindow", "Win2"))
self.btn_close.setText(_translate("MainWindow", "close"))
def on_close(self):
# win2 = QMainWindow()
# ui = Ui_Win2()
# ui.setupUi(win2)
self.MainWindow.close()
if __name__ == '__main__':
import sys
app = QApplication(sys.argv)
win2 = QMainWindow()
ui = Ui_Win2()
ui.setupUi(win2)
win2.show()
sys.exit(app.exec_())
call close function from self.MainWindow instead of self. and set self.MainWindow in first line of setupUi function

Why my QThread class drastically slows PyQT5 app?

I'm facing the problem with Threads. I'm displaying current CPU usage with progress bar and it seems to be working well but the performance of whole window is terrible. Can't even click the button without laggy behavior. Is there any simple solution to fix it?
Here is my main code
from PyQt5 import QtCore, QtGui, QtWidgets
from PyQt5.QtCore import QThread, pyqtSignal
import progressBarUI
import sys
import sysnfo
class MainWindow(QtWidgets.QMainWindow, progressBarUI.Ui_MainWindow):
def __init__(self, parent = None):
super(MainWindow, self).__init__(parent)
self.setupUi(self)
self.threadclass = ThreadClass()
self.threadclass.start()
self.threadclass.signal.connect(self.updateProgressBar)
def updateProgressBar(self):
current_percentage = sysnfo.getCpuPercentage()
self.progressBar.setValue(current_percentage)
class ThreadClass(QThread):
signal = pyqtSignal(int)
def __init__(self, parent=None):
super(ThreadClass, self).__init__(parent)
def run(self):
while True:
current_percentage = sysnfo.getCpuPercentage()
self.signal.emit(current_percentage)
if __name__ == "__main__":
app = QtWidgets.QApplication(sys.argv)
mainAppWin = MainWindow()
mainAppWin.show()
app.exec_()
Here is sysnfo module:
import psutil as ps
def getCpuPercentage():
return ps.cpu_percent(interval=1)
And UI file (converted to .py file):
from PyQt5 import QtCore, QtGui, QtWidgets
class Ui_MainWindow(object):
def setupUi(self, MainWindow):
MainWindow.setObjectName("MainWindow")
MainWindow.resize(787, 203)
self.centralwidget = QtWidgets.QWidget(MainWindow)
self.centralwidget.setObjectName("centralwidget")
self.progressBar = QtWidgets.QProgressBar(self.centralwidget)
self.progressBar.setGeometry(QtCore.QRect(370, 20, 381, 111))
self.progressBar.setProperty("value", 0)
self.progressBar.setObjectName("progressBar")
self.pushButton = QtWidgets.QPushButton(self.centralwidget)
self.pushButton.setGeometry(QtCore.QRect(20, 50, 151, 41))
self.pushButton.setObjectName("pushButton")
MainWindow.setCentralWidget(self.centralwidget)
self.menubar = QtWidgets.QMenuBar(MainWindow)
self.menubar.setGeometry(QtCore.QRect(0, 0, 787, 21))
self.menubar.setObjectName("menubar")
MainWindow.setMenuBar(self.menubar)
self.statusbar = QtWidgets.QStatusBar(MainWindow)
self.statusbar.setObjectName("statusbar")
MainWindow.setStatusBar(self.statusbar)
self.retranslateUi(MainWindow)
QtCore.QMetaObject.connectSlotsByName(MainWindow)
def retranslateUi(self, MainWindow):
_translate = QtCore.QCoreApplication.translate
MainWindow.setWindowTitle(_translate("MainWindow", "MainWindow"))
self.pushButton.setText(_translate("MainWindow", "Click me"))
if __name__ == "__main__":
import sys
app = QtWidgets.QApplication(sys.argv)
MainWindow = QtWidgets.QMainWindow()
ui = Ui_MainWindow()
ui.setupUi(MainWindow)
MainWindow.show()
sys.exit(app.exec_())

When you use the "interval" parameter you are indicating that it measures the information during that time and calculates the average causing the execution of that function to take "interval" seconds, and the correct thing is to execute it in another thread, but you make the mistake of executing it too in the updateProgressBar method that lives in the main thread blocking it, instead use the information that sends you the signal:
#QtCore.pyqtSlot(int)
def updateProgressBar(self, percentage):
self.progressBar.setValue(percentage)

How to kill the QRunnable in PyQt5?

I have an app with two buttons start and end. The start button will start a thread, which runs the audio recording function. This function is written using sounddevice and soundfile libraries. The audio recording can take place for an arbitary duration and the user can stop anytime by pressing ctrl+c.
So, now I want to implement a function for the end button to stop the thread which started by pressing start button or the function can send ctrl+c signal to the thread. So, that the current recording will be stopped. I am not sure how to achieve this. Any help is appreciated.
The code consisting in two .py is as it follows:
audio_record.py
import os
import signal
from PyQt5.QtGui import *
from PyQt5.QtWidgets import *
from PyQt5.QtCore import *
import time
import queue
from PyQt5 import QtCore, QtGui, QtWidgets
import soundfile as sf
import sounddevice as sd
import mythreading
class Ui_MainWindow(object):
def __init__(self):
self.threadpool = QThreadPool()
print("Multithreading with maximum %d threads" % self.threadpool.maxThreadCount())
def setupUi(self, MainWindow):
MainWindow.setObjectName("MainWindow")
MainWindow.resize(640, 480)
self.centralwidget = QtWidgets.QWidget(MainWindow)
self.centralwidget.setObjectName("centralwidget")
self.pushButton = QtWidgets.QPushButton(self.centralwidget)
self.pushButton.setGeometry(QtCore.QRect(280, 190, 75, 23))
self.pushButton.setObjectName("pushButton")
self.pushButton.clicked.connect(self.start_button_func)
self.pushButton_1 = QtWidgets.QPushButton(self.centralwidget)
self.pushButton_1.setGeometry(QtCore.QRect(380, 190, 75, 23))
self.pushButton_1.setObjectName("pushButton")
self.pushButton_1.clicked.connect(self.end_button_func)
MainWindow.setCentralWidget(self.centralwidget)
self.menubar = QtWidgets.QMenuBar(MainWindow)
self.menubar.setGeometry(QtCore.QRect(0, 0, 640, 21))
self.menubar.setObjectName("menubar")
MainWindow.setMenuBar(self.menubar)
self.statusbar = QtWidgets.QStatusBar(MainWindow)
self.statusbar.setObjectName("statusbar")
MainWindow.setStatusBar(self.statusbar)
self.retranslateUi(MainWindow)
QtCore.QMetaObject.connectSlotsByName(MainWindow)
def retranslateUi(self, MainWindow):
_translate = QtCore.QCoreApplication.translate
MainWindow.setWindowTitle(_translate("MainWindow", "MainWindow"))
self.pushButton.setText(_translate("MainWindow", "Start"))
self.pushButton_1.setText(_translate("MainWindow", "End"))
def record(self):
self.pid = os.getpid()
self.q = queue.Queue()
self.s = sd.InputStream(samplerate=48000, channels=2, callback=self.callback)
try:
# Make sure the file is open before recording begins
with sf.SoundFile('check.wav', mode='x', samplerate=48000, channels=2, subtype="PCM_16") as file:
with self.s:
# 1 second silence before the recording begins
time.sleep(1)
print('START')
print('#' * 80)
print('press Ctrl+C to stop the recording')
while True:
file.write(self.q.get())
except OSError:
print('The file to be recorded already exists.')
sys.exit(1)
def callback(self, indata, frames, time, status):
"""
This function is called for each audio block from the record function.
"""
if status:
print(status, file=sys.stderr)
self.q.put(indata.copy())
def start_button_func(self):
self.worker = mythreading.Worker(self.record)
self.threadpool.start(self.worker)
def end_button_func(self):
print('how to stop?')
if __name__ == "__main__":
import sys
app = QtWidgets.QApplication(sys.argv)
MainWindow = QtWidgets.QMainWindow()
ui = Ui_MainWindow()
ui.setupUi(MainWindow)
MainWindow.show()
sys.exit(app.exec_())
mythreading.py is as follows:
from PyQt5.QtGui import *
from PyQt5.QtWidgets import *
from PyQt5.QtCore import *
class Worker(QRunnable):
def __init__(self, fn, *args, **kwargs):
super(Worker, self).__init__()
self.fn = fn
#pyqtSlot()
def run(self):
self.fn()

You have to use a flag, in this case threading.Event() to indicate that the thread should no longer be executed. For the case of Ctrl + C you must use QShortcut
import os
import queue
from PyQt5 import QtCore, QtGui, QtWidgets
import soundfile as sf
import sounddevice as sd
import mythreading
import threading
class Ui_MainWindow(object):
def setupUi(self, MainWindow):
MainWindow.setObjectName("MainWindow")
MainWindow.resize(640, 480)
self.centralwidget = QtWidgets.QWidget(MainWindow)
self.centralwidget.setObjectName("centralwidget")
self.pushButton = QtWidgets.QPushButton(self.centralwidget)
self.pushButton.setGeometry(QtCore.QRect(280, 190, 75, 23))
self.pushButton.setObjectName("pushButton")
self.pushButton_1 = QtWidgets.QPushButton(self.centralwidget)
self.pushButton_1.setGeometry(QtCore.QRect(380, 190, 75, 23))
self.pushButton_1.setObjectName("pushButton")
MainWindow.setCentralWidget(self.centralwidget)
self.menubar = QtWidgets.QMenuBar(MainWindow)
self.menubar.setGeometry(QtCore.QRect(0, 0, 640, 21))
self.menubar.setObjectName("menubar")
MainWindow.setMenuBar(self.menubar)
self.statusbar = QtWidgets.QStatusBar(MainWindow)
self.statusbar.setObjectName("statusbar")
MainWindow.setStatusBar(self.statusbar)
self.retranslateUi(MainWindow)
QtCore.QMetaObject.connectSlotsByName(MainWindow)
def retranslateUi(self, MainWindow):
_translate = QtCore.QCoreApplication.translate
MainWindow.setWindowTitle(_translate("MainWindow", "MainWindow"))
self.pushButton.setText(_translate("MainWindow", "Start"))
self.pushButton_1.setText(_translate("MainWindow", "End"))
class MainWindow(QtWidgets.QMainWindow, Ui_MainWindow):
def __init__(self, parent=None):
super(MainWindow, self).__init__(parent)
self.setupUi(self)
self.threadpool = QtCore.QThreadPool()
print("Multithreading with maximum %d threads" % self.threadpool.maxThreadCount())
self.pushButton.clicked.connect(self.start_button_func)
self.pushButton_1.clicked.connect(self.end_button_func)
self.event_stop = threading.Event()
QtWidgets.QShortcut("Ctrl+C", self, activated=self.end_button_func)
def record(self):
self.pid = os.getpid()
self.q = queue.Queue()
self.s = sd.InputStream(samplerate=48000, channels=2, callback=self.callback)
try:
# Make sure the file is open before recording begins
with sf.SoundFile('check.wav', mode='x', samplerate=48000, channels=2, subtype="PCM_16") as file:
with self.s:
# 1 second silence before the recording begins
QtCore.QThread.sleep(1)
print('START')
print('#' * 80)
print('press Ctrl+C to stop the recording')
while not self.event_stop.is_set():
file.write(self.q.get())
print("STOP")
except OSError:
print('The file to be recorded already exists.')
sys.exit(1)
def callback(self, indata, frames, time, status):
if status:
print(status, file=sys.stderr)
self.q.put(indata.copy())
#QtCore.pyqtSlot()
def start_button_func(self):
print("start")
self.worker = mythreading.Worker(self.record)
self.threadpool.start(self.worker)
#QtCore.pyqtSlot()
def end_button_func(self):
print('how to stop?')
self.event_stop.set()
if __name__ == "__main__":
import sys
app = QtWidgets.QApplication(sys.argv)
w = MainWindow()
w.show()
sys.exit(app.exec_())

How to pause/play a thread in PyQT5?

I'm making a light GUI program with PyQT5.
But now I'm facing some problem about thread.
I just made simple test program like bottom:
the program simply trying to append numbers to textbox, but it crashes.
I don't know why but somehow I can prevent it by removing a comment(time.sleep)
import sys
import threading
import time
from PyQt5.QtCore import *
from PyQt5.QtWidgets import *
class Some(QWidget):
e = threading.Event()
def btnfunc(self):
self.e.set()
def __init__(self):
super().__init__()
self.myButton = QPushButton('do next')
self.logs = QTextEdit()
self.mylay = QVBoxLayout()
self.mylay.addWidget(self.myButton)
self.mylay.addWidget(self.logs)
self.setLayout(self.mylay)
self.setGeometry(300, 300, 300, 550)
self.setWindowTitle('mytest')
self.show()
t = threading.Thread(target=self.myfunc, args=( ))
t.start()
self.myButton.clicked.connect(self.btnfunc)
def myfunc(self):
for i in range(300):
# time.sleep(0.4)
self.logs.append(str(i))
if i == 20:
self.e.wait()
app = QApplication(sys.argv)
ex = Some()
sys.exit(app.exec_())
It would be better if sets time higher.
I thought it is because of resource accessing, since it is pyQT5 GUI.
So I've find QThread. and I tried like bottom,
import sys
import time
from PyQt5.QtCore import *
from PyQt5.QtWidgets import *
class Some(QWidget):
qw = QWaitCondition()
qm = QMutex()
def btnfunc(self):
self.qw.wakeAll()
def __init__(self):
super().__init__()
self.myButton = QPushButton('do next')
self.logs = QTextEdit()
self.mylay = QVBoxLayout()
self.mylay.addWidget(self.myButton)
self.mylay.addWidget(self.logs)
self.setLayout(self.mylay)
self.setGeometry(300, 300, 300, 550)
self.setWindowTitle('mytest')
self.show()
self.myButton.clicked.connect(self.btnfunc)
self.thread = QThread()
self.thread.started.connect(self.myfunc)
self.thread.start()
def myfunc(self):
for i in range(300):
self.logs.append(str(i))
if i == 20:
self.qw.wait(self.qm)
app = QApplication(sys.argv)
ex = Some()
sys.exit(app.exec_())
But crashes, doesn't work. and tried QThread+threading.Event(). It freezes GUI.
Now I don't know how to proceed it...
Edit:
I just realized about thread. Should not be accessed from other thread except QThread.
Then I will keep find about QWaitCondition

You should not control GUI directly via multithreading. Since two different threads are trying to control the GUI this results to freeze or crash.
I have learnt about this concept from here http://www.xyzlang.com/python/PyQT5/pyqt_multithreading.html
Here is your code that will work perfectly.
import sys
import threading
import time
from PyQt5.QtCore import *
from PyQt5.QtWidgets import *
# Added new
class Communicate(QObject):
signal = pyqtSignal(str)
class Some(QWidget):
e = threading.Event()
def btnfunc(self):
self.e.set()
def __init__(self):
super().__init__()
#communicate object
self.comm = Communicate()
self.comm.signal.connect(self.append_data)
self.myButton = QPushButton('do next')
self.logs = QTextEdit()
self.mylay = QVBoxLayout()
self.mylay.addWidget(self.myButton)
self.mylay.addWidget(self.logs)
self.setLayout(self.mylay)
self.setGeometry(300, 300, 300, 550)
self.setWindowTitle('mytest')
self.show()
t = threading.Thread(target=self.myfunc, args=( ))
t.start()
self.myButton.clicked.connect(self.btnfunc)
def myfunc(self):
for i in range(300):
# time.sleep(0.4)
#self.logs.append(str(i))
self.comm.signal.emit(str(i))
if i == 20:
self.e.wait()
def append_data(self, data):
self.logs.append(data)
app = QApplication(sys.argv)
ex = Some()
sys.exit(app.exec_())

You can pause the loop by using while = True and you can stop the loop with break statement
from PyQt5 import QtCore, QtGui, QtWidgets
from PyQt5.QtCore import (
Qt, QObject, pyqtSignal, pyqtSlot, QRunnable, QThreadPool
)
import time
from time import sleep
import threading
class Ui_MainWindow(object):
def setupUi(self, MainWindow):
MainWindow.setObjectName("MainWindow")
MainWindow.resize(655, 589)
self.centralwidget = QtWidgets.QWidget(MainWindow)
self.centralwidget.setObjectName("centralwidget")
self.run = QtWidgets.QPushButton(self.centralwidget)
self.run.setGeometry(QtCore.QRect(260, 50, 93, 28))
self.run.setObjectName("run")
self.result = QtWidgets.QTextEdit(self.centralwidget)
self.result.setGeometry(QtCore.QRect(110, 120, 491, 201))
self.result.setObjectName("result")
self.stop = QtWidgets.QPushButton(self.centralwidget)
self.stop.setGeometry(QtCore.QRect(110, 390, 93, 28))
self.stop.setObjectName("stop")
self.pause = QtWidgets.QPushButton(self.centralwidget)
self.pause.setGeometry(QtCore.QRect(300, 390, 93, 28))
self.pause.setObjectName("pause")
self.resume = QtWidgets.QPushButton(self.centralwidget)
self.resume.setGeometry(QtCore.QRect(480, 390, 93, 28))
self.resume.setObjectName("resume")
MainWindow.setCentralWidget(self.centralwidget)
self.menubar = QtWidgets.QMenuBar(MainWindow)
self.menubar.setGeometry(QtCore.QRect(0, 0, 655, 26))
self.menubar.setObjectName("menubar")
MainWindow.setMenuBar(self.menubar)
self.statusbar = QtWidgets.QStatusBar(MainWindow)
self.statusbar.setObjectName("statusbar")
MainWindow.setStatusBar(self.statusbar)
self.retranslateUi(MainWindow)
QtCore.QMetaObject.connectSlotsByName(MainWindow)
def retranslateUi(self, MainWindow):
_translate = QtCore.QCoreApplication.translate
MainWindow.setWindowTitle(_translate("MainWindow", "MainWindow"))
self.run.setText(_translate("MainWindow", "Run"))
self.stop.setText(_translate("MainWindow", "stop"))
self.pause.setText(_translate("MainWindow", "Pause"))
self.resume.setText(_translate("MainWindow", "Resume"))
class MainWindow(QtWidgets.QMainWindow, Ui_MainWindow):
def __init__(self, parent=None):
super().__init__(parent)
self.setupUi(self)
self.is_paused = False
self.is_killed = False
self.run.clicked.connect(self.send_wala)
self.stop.clicked.connect(self.kill_g)
self.pause.clicked.connect(self.pause_g)
self.resume.clicked.connect(self.resume_g)
#QtCore.pyqtSlot()
def send_wala(self):
threading.Thread(target=self.working, daemon=True).start()
def working(self):
for i in range(10):
sleep(3)
self.result.append(str(i))
while self.is_paused:
time.sleep(0)
if self.is_killed:
break
def pause_g(self):
self.is_paused = True
def resume_g(self):
self.is_paused = False
def kill_g(self):
self.is_killed = True
import sys
if __name__ == "__main__":
app = QtWidgets.QApplication(sys.argv)
w = MainWindow()
w.show()
sys.exit(app.exec_())