The blocking tasks are not friendly with the event loop where the GUI is executed as they prevent the normal tasks that the GUI performs such as ticket checking, redrawing, etc. from being executed.
The solution in these cases is to use thread to execute the blocking task and use the signals to send the information.
import sys
from PyQt5 import QtCore, QtWidgets
from selenium import webdriver
class SeleniumWorker(QtCore.QObject):
progressChanged = QtCore.pyqtSignal(int)
def doWork(self):
progress = 0
browser = webdriver.Firefox()
links = ['http://www.somesite.com/',
'http://www.somesite.com/page2',
'http://www.somesite.com/page3']
for link in links:
browser.get(link)
progress += 100 / len(links)
self.progressChanged.emit(progress)
browser.close()
class Widget(QtWidgets.QWidget):
def __init__(self, *args, **kwargs):
QtWidgets.QWidget.__init__(self, *args, **kwargs)
lay = QtWidgets.QHBoxLayout(self)
progressBar = QtWidgets.QProgressBar()
progressBar.setRange(0, 100)
button = QtWidgets.QPushButton("Start")
lay.addWidget(progressBar)
lay.addWidget(button)
self.thread = QtCore.QThread()
self.worker = SeleniumWorker()
self.worker.moveToThread(self.thread)
self.thread.started.connect(self.worker.doWork)
button.clicked.connect(self.thread.start)
self.worker.progressChanged.connect(progressBar.setValue, QtCore.Qt.QueuedConnection)
if __name__ == '__main__':
app = QtWidgets.QApplication(sys.argv)
w = Widget()
w.show()
sys.exit(app.exec_())