[Python] Waiting for a PyQt/PySide.QtCore.QThread to finish before doing something

I have a data acquisition thread which samples and processes data which it then emits as a signal to a receiver.

Now, when that thread is stopped, how can I ensure it has finished the current loop and emitted its signal before proceeding (and e.g. emitting a summary signal)?

import sys
import time

from PySide6.QtCore import Signal, Slot
from PySide6 import QtCore
from PySide6 import QtWidgets


##==============================================================================
class EmitterClassThreaded(QtCore.QThread):
## Define a signal that emits a dictionary
data_signal = Signal(dict)

##--------------------------------------------------------------------------
def __init__(self):
super().__init__()
self.counter = 0
self.t_start = time.time()
self.running = True

## Connect the signal to a method within the same class
self.data_signal.connect(self.handle_data)

##--------------------------------------------------------------------------
def run(self):
while self.running:
self.counter += 1
now = time.time() - self.t_start
data = {'counter': self.counter, 'timestamp': f"{now:.1f}"}
time.sleep(1) # <------ doing something here which takes time
self.data_signal.emit(data)

##--------------------------------------------------------------------------
def stop(self):
self.running = False

##--------------------------------------------------------------------------
@Slot(dict)
def handle_data(self, data):
print(f"EmitterClassThreaded received data: {data}")


##==============================================================================
class ReceiverClass():
def __init__(self):
super().__init__()

##--------------------------------------------------------------------------
@Slot(dict)
def handle_data(self, data):
print(f"ReceiverClass received data: {data}")


##==============================================================================
class MainWindow(QtWidgets.QMainWindow):
def __init__(self):
super().__init__()

self.setWindowTitle("Example ThreadedEmitter-Receiver")
self.setGeometry(100, 100, 400, 200)

self.label = QtWidgets.QLabel("Waiting for signal...", self)
self.label.move(150, 80)

self.stop_button = QtWidgets.QPushButton("Stop Emitter", self)
self.stop_button.move(150, 120)
self.stop_button.clicked.connect(self.stop_emitter)

self.emitter = EmitterClassThreaded()
self.emitter.data_signal.connect(self.handle_data)

self.receiver = ReceiverClass()

## Connect the signal from EmitterClass to the method in ReceiverClass
self.emitter.data_signal.connect(self.receiver.handle_data)

## Start the emitter thread
self.emitter.start()
self.emitter.running = True

##--------------------------------------------------------------------------
@Slot(dict)
def handle_data(self, data):
self.label.setText(f"Counter: {data['counter']}\nTimestamp: {data['timestamp']}")

##--------------------------------------------------------------------------
def stop_emitter(self):
print("ReceiverClass: Stopping the emitter thread...")
self.emitter.stop()
## TODO: Wait for the thread to finish (incl. emitting the last signal) before proceeding
print("Creating own data to emit.")
self.emitter.data_signal.emit({'counter': -999, 'timestamp': 0})

##******************************************************************************
##******************************************************************************
if __name__ == "__main__":
app = QtWidgets.QApplication(sys.argv)
window = MainWindow()
window.show()
sys.exit(app.exec())


In my current example, the last signal from the thread always overwrites that summary signal. Thanks in advance!

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