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PyQt: qthread interrupt via signals

I am new to pyqt, so I hope that there’s nothing wrong with what I'm trying to do. I tried to create an interaction between QThreads using PyQt signals. In particular, what I would like to do is to emit a signal from a stream, and this signal must interrupt what the stream does to run a particular method. By the way, I have problems with this, so I wonder if what I'm trying to do is legal.

For example, now I was trying to do something like this:

import sys
import time
from PyQt4 import QtGui as qt
from PyQt4 import QtCore as qtcore
from PyQt4.QtCore import QThread
import threading

app = qt.QApplication(sys.argv)
class widget(qt.QWidget):

    def __init__(self, parent=None):
        qtcore.QObject.__init__(self)


    def appinit(self):
        self.mysignal = qtcore.SIGNAL("mysignal")
        thread = mythread(self)
        thread.start()
        time.sleep(5)
        print "before emit",str(threading.current_thread())
        self.emit(self.mysignal,"hello, I'm thread "+str(threading.current_thread()))
        print "after emit",str(threading.current_thread())



class mythread(QThread):
    def __init__(self,parent):
        qtcore.QThread.__init__(self, parent=app)
        self.parent=parent

    def run(self):
        self.mysignal = qtcore.SIGNAL("mysignal")
        self.connect(self.parent, self.mysignal, self.myfunc)
        for i in range(15):
            print "**",threading.current_thread(),i
            time.sleep(1)

    def myfunc(self, msg):
        print threading.current_thread(), msg, "Enter"
        time.sleep(5)
        print threading.current_thread(), msg, "Exit"


def main():
    mywidget = widget()
    mywidget.show()
    qtcore.QTimer.singleShot(0, mywidget.appinit)
    sys.exit(app.exec_())

main()

The output I get is:

** <_DummyThread(Dummy-1, started daemon 1968)> 0
** <_DummyThread(Dummy-1, started daemon 1968)> 1
** <_DummyThread(Dummy-1, started daemon 1968)> 2
** <_DummyThread(Dummy-1, started daemon 1968)> 3
** <_DummyThread(Dummy-1, started daemon 1968)> 4
before emit <_MainThread(MainThread, started 2928)>
<_MainThread(MainThread, started 2928)> hello, I'm thread <_MainThread(MainThread, started 2928)> Enter
** <_DummyThread(Dummy-1, started daemon 1968)> 5
** <_DummyThread(Dummy-1, started daemon 1968)> 6
** <_DummyThread(Dummy-1, started daemon 1968)> 7
** <_DummyThread(Dummy-1, started daemon 1968)> 8
** <_DummyThread(Dummy-1, started daemon 1968)> 9
<_MainThread(MainThread, started 2928)> hello, I'm thread <_MainThread(MainThread, started 2928)> Exit
after emit <_MainThread(MainThread, started 2928)>
** <_DummyThread(Dummy-1, started daemon 1968)> 10
** <_DummyThread(Dummy-1, started daemon 1968)> 11
** <_DummyThread(Dummy-1, started daemon 1968)> 12
** <_DummyThread(Dummy-1, started daemon 1968)> 13
** <_DummyThread(Dummy-1, started daemon 1968)> 14

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import sys
import time
from PyQt4 import QtGui as qt
from PyQt4 import QtCore as qtcore
from PyQt4.QtCore import QThread
import threading

app = qt.QApplication(sys.argv)
class widget(qt.QWidget):

    def __init__(self, parent=None):
        qtcore.QObject.__init__(self)


    def appinit(self):
        self.mysignal = qtcore.SIGNAL("mysignal")
        thread = mythread(self,self.mysignal)
        thread.start()
        time.sleep(5)
        print "before emit",str(threading.current_thread())
        self.emit(self.mysignal,"hello, I'm thread "+str(threading.current_thread()))
        print "after emit",str(threading.current_thread())



class mythread(QThread):
    def __init__(self,parent,sig):
        qtcore.QThread.__init__(self, parent=app)
        self.parent=parent
        self.mysignal = sig
        self.stop_event=threading.Event()
        self.connect(self.parent, self.mysignal, self.setIt)

    def run(self):

        for i in range(15):
            if self.stop_event.isSet():
                self.myfunc()
            print "**",threading.current_thread(),i
            time.sleep(1)

    def setIt(self,msg):
        self.stop_event.set()
        self.msg = msg

    def myfunc(self):
        print threading.current_thread(),self.msg ,  "Enter"
        time.sleep(5)
        print threading.current_thread(),self.msg ,  "Exit"
        self.stop_event.clear()


def main():
    mywidget = widget()
    mywidget.show()
    qtcore.QTimer.singleShot(0, mywidget.appinit)
    sys.exit(app.exec_())

main()

:

** <_DummyThread(Dummy-1, started daemon 7312)> 0
** <_DummyThread(Dummy-1, started daemon 7312)> 1
** <_DummyThread(Dummy-1, started daemon 7312)> 2
** <_DummyThread(Dummy-1, started daemon 7312)> 3
** <_DummyThread(Dummy-1, started daemon 7312)> 4
before emit <_MainThread(MainThread, started 232)>
after emit <_MainThread(MainThread, started 232)>
<_DummyThread(Dummy-1, started daemon 7312)> hello, I'm thread <_MainThread(MainThread,     started 232)> Enter
<_DummyThread(Dummy-1, started daemon 7312)> hello, I'm thread <_MainThread(MainThread,     started 232)> Exit
** <_DummyThread(Dummy-1, started daemon 7312)> 5
** <_DummyThread(Dummy-1, started daemon 7312)> 6
** <_DummyThread(Dummy-1, started daemon 7312)> 7
** <_DummyThread(Dummy-1, started daemon 7312)> 8
** <_DummyThread(Dummy-1, started daemon 7312)> 9
** <_DummyThread(Dummy-1, started daemon 7312)> 10
** <_DummyThread(Dummy-1, started daemon 7312)> 11
** <_DummyThread(Dummy-1, started daemon 7312)> 12
** <_DummyThread(Dummy-1, started daemon 7312)> 13
** <_DummyThread(Dummy-1, started daemon 7312)> 14
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