PyQt4:如何暂停线程直到发出信号？

Question

我有以下pyqtmain.py：

#!/usr/bin/python3
import sys
from PyQt4.QtCore import *
from PyQt4.QtGui import *
from pyqtMeasThread import *


class MainWindow(QMainWindow):
    def __init__(self, parent=None):
        self.qt_app = QApplication(sys.argv)
        QMainWindow.__init__(self, parent)

        buttonWidget = QWidget()
        rsltLabel = QLabel("Result:")
        self.rsltFiled = QLineEdit()
        self.buttonStart = QPushButton("Start")

        verticalLayout = QVBoxLayout(buttonWidget)
        verticalLayout.addWidget(rsltLabel)
        verticalLayout.addWidget(self.rsltFiled)
        verticalLayout.addWidget(self.buttonStart)

        butDW = QDockWidget("Control", self)
        butDW.setWidget(buttonWidget)
        self.addDockWidget(Qt.LeftDockWidgetArea, butDW)

        self.mthread = QThread()  # New thread to run the Measurement Engine
        self.worker = MeasurementEngine()  # Measurement Engine Object

        self.worker.moveToThread(self.mthread)
        self.mthread.finished.connect(self.worker.deleteLater)  # Cleanup after thread finished

        self.worker.measure_msg.connect(self.showRslt)

        self.buttonStart.clicked.connect(self.worker.run)

        # Everything configured, start the worker thread.
        self.mthread.start()

    def run(self):
        """ Show the window and start the event loop """
        self.show()
        self.qt_app.exec_()  # Start event loop

    @pyqtSlot(str)
    def showRslt(self, mystr):
        self.rsltFiled.setText(mystr)


def main():
    win = MainWindow()
    win.run()


if __name__ == '__main__':
    main()

以及另一个执行实际测量的线程脚本：

from PyQt4.QtCore import *
import time

class MeasurementEngine(QObject):
    measure_msg = pyqtSignal(str)
    def __init__(self):
        QObject.__init__(self)  # Don't forget to call base class constructor

    @pyqtSlot()
    def run(self):
        self.measure_msg.emit('phase1')
        time.sleep(2) # here I would like to make it as an interrupt
        self.measure_msg.emit('phase2')

这段代码现在所做的是在按下Start按钮之后，将执行在线程中运行的函数。然而，实际上在函数运行中，有两个测量阶段。现在我用了延时。

但我想实际实现的是，在“阶段1”测量完成后。将弹出一个消息框，同时暂停/保持线程。在用户关闭消息框之前，线程函数将继续。