Example of using QThread and communicating progress

thread_example.py

import time

from PySide import QtCore, QtGui

class Simulation(QtCore.QThread):
    updateRange = QtCore.Signal(int, int)
    updateProgress = QtCore.Signal(int)

    def __init__(self, parent=None):
        QtCore.QThread.__init__(self, parent)
        self._count = 0

    @QtCore.Slot(int)
    def setCount(self, count):
        self._count = count

    def run(self):
        self.updateRange.emit(0, self._count)

        for i in range(self._count):
            print(i)
            self.updateProgress.emit(i)
            time.sleep(10)

        self.updateProgress.emit(i + 1)


class Window(QtGui.QWidget):
    def __init__(self):
        super(Window, self).__init__()
        self.simulation = Simulation()

        layout = QtGui.QGridLayout()

        self.progressBar = QtGui.QProgressBar()
        self.simulation.updateRange.connect(self.progressBar.setRange)
        self.simulation.updateProgress.connect(self.progressBar.setValue)
        layout.addWidget(self.progressBar, 0, 0, 1, 3)

        self.countSpinBox = QtGui.QSpinBox()
        self.countSpinBox.setRange(0, 10)
        self.countSpinBox.setValue(2)
        layout.addWidget(QtGui.QLabel('Count:'), 1, 0)
        layout.addWidget(self.countSpinBox, 1, 1)

        self.pushButton = QtGui.QPushButton('Run')
        self.pushButton.clicked.connect(self.start)
        layout.addWidget(self.pushButton, 1, 2)

        self.setLayout(layout)

    @QtCore.Slot()
    def start(self):
        self.simulation.setCount(self.countSpinBox.value())
        self.simulation.start()


if __name__ == '__main__':
    import sys

    app = QtGui.QApplication(sys.argv)
    window = Window()
    window.show()
    sys.exit(app.exec_())