import sys
import time
from PySide import QtGui
from PySide import QtCore

class Worker(QtCore.QObject):

    finished = QtCore.Signal(bool)

    def __init__(self):
        super(Worker, self).__init__()

    def helloWorld(self):
        for i in xrange(10):
            print 'hello %s' % i
            time.sleep(.5)

class MainUI(QtGui.QWidget):

    def __init__(self, parent=None):

        super(MainUI, self).__init__(parent)
        self.extraThread = QtCore.QThread()
        self.worker = Worker()
        self.worker.moveToThread(self.extraThread)
        self.setupUI()
        self.connectSignalsAndSlots()


    def setupUI(self):
        # CREAT MAIN LAYOUT AND WIDGETS
        mainLayout = QtGui.QVBoxLayout()
        btnLayout = QtGui.QHBoxLayout()
        mainLayout.addLayout(btnLayout)
        self.setLayout(mainLayout)

        self.progressBar = QtGui.QProgressBar(self)
        self.progressBar.setVisible(False)
        self.btnWork = QtGui.QPushButton('Do Work')
        self.btnCancel = QtGui.QPushButton('Cancel')
        self.btnCancel.setDisabled(True)

        self.outputWindow = QtGui.QTextEdit()

        mainLayout.addWidget(self.progressBar)
        mainLayout.addWidget(self.outputWindow)

        btnLayout.addWidget(self.btnWork)
        btnLayout.addWidget(self.btnCancel)


    def connectSignalsAndSlots(self):
        print 'connecting signals'
        self.btnWork.clicked.connect(self.startWorker)
        self.btnCancel.clicked.connect(self.extraThread.terminate)

        # THREAD STARTED
        self.extraThread.started.connect(lambda: self.btnWork.setDisabled(True))
        self.extraThread.started.connect(lambda: self.btnCancel.setEnabled(True))
        self.extraThread.started.connect(self.progressBar.show)
        self.extraThread.started.connect(self.worker.helloWorld)

        # THREAD FINISHED
        self.extraThread.finished.connect(lambda: self.btnCancel.setDisabled(True))
        self.extraThread.finished.connect(self.extraThread.deleteLater)
        self.extraThread.finished.connect(self.worker.deleteLater)

        # SHOW PROGRESS BAR WHEN PUBLISHING STARTS
        self.extraThread.started.connect(self.progressBar.show)
        # CONNECT PROCESS TO PROGRESS BAR AND OUTPUT WINDOW
        # NOT DONE YET

    def startWorker(self):
        # GO
        print 'starting worker thread'
        self.extraThread.start()
        for i in xrange(10):
            print 'from main thread:', i
            time.sleep(.3)



if __name__ == '__main__':
    args = sys.argv
    app = QtGui.QApplication(args)
    p = MainUI()
    p.show()
    sys.exit(app.exec_())