SetText in Pyqt5

Question

I am developing an application in pyqt5 and I ran into one problem. There is a script that receives data, and in pyqt5 in the line "main_text.setText (str (TEXT))" I output them, and in the format "str" But the script itself receives and outputs data every 0.2s, but in the line "main_text.setText (str (TEXT))" they are not updated. Tried through the time sleep function, the app doesn't work,

what method in pyqt5 can be used to output different data to the same set text ?

My code :

from PyQt5 import QtWidgets
from PyQt5.QtWidgets import QApplication, QMainWindow

import sys
import MetaTrader5 as mt5

import time

mt5.initialize()

ticket_info = mt5.symbol_info_tick("EURUSD")._asdict()
bid_usd = mt5.symbol_info_tick("EURUSD").bid

def applecation():
    app = QApplication(sys.argv)
    window = QMainWindow()

    window.setWindowTitle('Test Programm')
    window.setGeometry(300, 250, 350, 200)


    main_text = QtWidgets.QLabel(window)
    main_text.setText(str(bid_usd))
    main_text.move(100,100)
    main_text.adjustSize()

    window.show()

    sys.exit(app.exec_())

if __name__ == "__main__":
    applecation()

eyllanesc · Accepted Answer · 2021-03-10T06:56:10.230

2

You are invoking the symbol_info_tick method only once so you will only get a data, if you want to get that information every T seconds then you must use a while True that is executed in a secondary thread so that it does not block the GUI and send the information through of signals.

import sys
import threading
import time

from PyQt5.QtCore import QObject, pyqtSignal
from PyQt5.QtWidgets import QApplication, QLabel, QMainWindow

import MetaTrader5 as mt5


class MetaTrader5Worker(QObject):
    dataChanged = pyqtSignal(str)

    def start(self):
        threading.Thread(target=self._execute, daemon=True).start()

    def _execute(self):
        mt5.initialize()
        while True:
            bid_usd = mt5.symbol_info_tick("EURUSD").bid
            self.dataChanged.emit(str(bid_usd))
            time.sleep(0.5)


class MainWindow(QMainWindow):
    def __init__(self, parent=None):
        super().__init__(parent)
        self.label = QLabel(self)
        self.setWindowTitle("Test Programm")
        self.setGeometry(300, 250, 350, 200)

    def handle_data_changed(self, text):
        self.label.setText(text)
        self.label.adjustSize()


def main():
    app = QApplication(sys.argv)

    window = MainWindow()
    window.show()

    worker = MetaTrader5Worker()
    worker.dataChanged.connect(window.handle_data_changed)
    worker.start()

    sys.exit(app.exec_())


if __name__ == "__main__":
    main()

edited Mar 10 '21 at 06:56

answered Mar 10 '21 at 06:46

eyllanesc

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Thanks for the answer. The program runs, but no text is output ... – xxxHEKETOSxxx Mar 10 '21 at 06:56
@xxxHEKETOSxxx oops, try again with updated code – eyllanesc Mar 10 '21 at 06:56
Can you clarify further .... I plan to display a lot of data this way .... do I need to repeat the code all the time or is there some better method? – xxxHEKETOSxxx Mar 10 '21 at 07:03
1

@xxxHEKETOSxxx The key is in the signals, in this case the signature of the signal is "str" but if you are going to handle much more information you can change it to a list, dictionaries or other elements. Note: SO is not a tutorial service so if you have other problems then you should investigate, if you are going to use Qt then check the thousands of examples that are in SO and others all over the internet – eyllanesc Mar 10 '21 at 07:05
Thanks for the answer) I will look for information in this direction. – xxxHEKETOSxxx Mar 10 '21 at 07:14

score 0 · Answer 2 · answered Nov 18 '21 at 17:54

You can use threading , it's easier to understand than QThreads

from PyQt5 import QtWidgets
from PyQt5.QtWidgets import QApplication, QMainWindow
import threading
import sys
import MetaTrader5 as mt5

import time

mt5.initialize()

ticket_info = mt5.symbol_info_tick("EURUSD")._asdict()
bid_usd = mt5.symbol_info_tick("EURUSD").bid

def applecation():
    app = QApplication(sys.argv)
    window = QMainWindow()

    window.setWindowTitle('Test Programm')
    window.setGeometry(300, 250, 350, 200)


    main_text = QtWidgets.QLabel(window)
    main_text.move(100,100)
    main_text.adjustSize()

    def update_text():
        while True:
            main_text.setText(str(bid_usd))
            time.sleep(0.2)

    t1 = threading.Thread(target = update_text())
    t1.start()


    window.show()

    sys.exit(app.exec_())

if __name__ == "__main__":
    applecation()

SetText in Pyqt5

2 Answers2