Question

i have a requirement where my execution will happen in threads and i want to emit signal from that thread to main class. below is my example code snippet, where i created the an instance of MainClass and assigned it to temp. where MainClass internally is connected to a thread Thread1 where the actual work will happen. when the signal is emitted from Thread1 i want the signalcalled definition to be executed which is connected from temp

Code snippet

class Thread1(QtCore.QThread):

    ThreadSignal = QtCore.pyqtSignal(str)

    While True:

        #some statments
        if Condition:
            ThreadSignal.emit('Yes')
        else:
            ThreadSignal.emit('No')

class MainClass(QtCore.QObject):

    MainSignal = QtCore.pyqtSignal(str)

    Testinstance = Thread1()

def signalcalled(s):

    print s

if __name__=='__main__':
    app = AtGui.QApplication(sys.argv)
    temp = MainClass()
    temp.MainSignal.connect(signalcalled)
    sys.exit(app.exec()_)

Answer 1

This should work:

#!/usr/bin/env python
#-*- coding:utf-8 -*-

from PyQt4 import QtCore, QtGui

class myThread(QtCore.QThread):
    threadSignal = QtCore.pyqtSignal(str)

    def __init__(self, parent=None):
        super(myThread, self).__init__(parent)

    def run(self):
        while True:
            if True:
                self.threadSignal.emit('Yes')

            else:
                self.threadSignal.emit('No')

            break

class myMainClass(QtCore.QObject):
    mainSignal = QtCore.pyqtSignal(str)

    def __init__(self, parent=None):
        super(myMainClass, self).__init__(parent)

        testInstance = myThread(self)
        testInstance.threadSignal.connect(self.mainSignal.emit)
        testInstance.start()

def signalcalled(s):
    print s

if __name__ == "__main__":
    import  sys

    app = QtGui.QApplication(sys.argv)
    main = myMainClass()
    main.mainSignal.connect(signalcalled)
    sys.exit(app.exec_())