How to use sleep() function to refresh text on a label?

strayaaaa

Hi all :)

I am trying to display the current time in a label. The below code works, but it is only a static display of the time, and the time does not change every second.

from asyncio import current_task
from PyQt5 import QtCore, QtGui, QtWidgets
import time

class Ui_MainWindow(object):
    def setupUi(self, MainWindow):
        MainWindow.setObjectName("MainWindow")
        MainWindow.resize(329, 93)
        self.centralwidget = QtWidgets.QWidget(MainWindow)
        self.centralwidget.setObjectName("centralwidget")
        self.label = QtWidgets.QLabel(self.centralwidget)
        self.label.setGeometry(QtCore.QRect(20, 20, 291, 51))
        font = QtGui.QFont()
        font.setPointSize(30)
        self.label.setFont(font)
        self.label.setFrameShape(QtWidgets.QFrame.Box)
        self.label.setAlignment(QtCore.Qt.AlignCenter)
        self.label.setObjectName("label")
        MainWindow.setCentralWidget(self.centralwidget)
        self.statusbar = QtWidgets.QStatusBar(MainWindow)
        self.statusbar.setObjectName("statusbar")
        MainWindow.setStatusBar(self.statusbar)

        self.retranslateUi(MainWindow)
        QtCore.QMetaObject.connectSlotsByName(MainWindow)

        t = time.localtime()
        current_time = time.strftime("%H:%M:%S", t)
        self.label.setText(str(current_time))

    def retranslateUi(self, MainWindow):
        _translate = QtCore.QCoreApplication.translate
        MainWindow.setWindowTitle(_translate("MainWindow", "Clock"))


if __name__ == "__main__":
    import sys
    app = QtWidgets.QApplication(sys.argv)
    MainWindow = QtWidgets.QMainWindow()
    ui = Ui_MainWindow()
    ui.setupUi(MainWindow)
    MainWindow.show()
    sys.exit(app.exec_())

So I had tried to use the sleep() function to rerun the time function, but that doesn't open a GUI window at all, even though there are no error messages, so the program is running, but a GUI window with the time doesn't appear on the screen.

Any help would be appreciated. Thanks in advance. :)

from asyncio import current_task
from PyQt5 import QtCore, QtGui, QtWidgets
import time


class Ui_MainWindow(object):
    def setupUi(self, MainWindow):
        MainWindow.setObjectName("MainWindow")
        MainWindow.resize(329, 93)
        self.centralwidget = QtWidgets.QWidget(MainWindow)
        self.centralwidget.setObjectName("centralwidget")
        self.label = QtWidgets.QLabel(self.centralwidget)
        self.label.setGeometry(QtCore.QRect(20, 20, 291, 51))
        font = QtGui.QFont()
        font.setPointSize(30)
        self.label.setFont(font)
        self.label.setFrameShape(QtWidgets.QFrame.Box)
        self.label.setAlignment(QtCore.Qt.AlignCenter)
        self.label.setObjectName("label")
        MainWindow.setCentralWidget(self.centralwidget)
        self.statusbar = QtWidgets.QStatusBar(MainWindow)
        self.statusbar.setObjectName("statusbar")
        MainWindow.setStatusBar(self.statusbar)

        self.retranslateUi(MainWindow)
        QtCore.QMetaObject.connectSlotsByName(MainWindow)

        while True:
            t = time.localtime()
            current_time = time.strftime("%H:%M:%S", t)
            self.label.setText(str(current_time))
            time.sleep(1)

    def retranslateUi(self, MainWindow):
        _translate = QtCore.QCoreApplication.translate
        MainWindow.setWindowTitle(_translate("MainWindow", "Clock"))

if __name__ == "__main__":
    import sys
    app = QtWidgets.QApplication(sys.argv)
    MainWindow = QtWidgets.QMainWindow()
    ui = Ui_MainWindow()
    ui.setupUi(MainWindow)
    MainWindow.show()
    sys.exit(app.exec_())

mchinand

Use a QTimer instead of sleep() and an infinite loop. https://pythonpyqt.com/qtimer/

0x4D6F652E51

Use QTimer and connect timeout signal to a slot that updates the text.

QObject::connect(*timer, &QTimer::timeout, *yourClass, yourClass::updateTextSlot);
timer->start(6000);

CristianMaureira

Hey @strayaaaa
I just pushed a simple example of a digital clock using QTimer to clarify the usage from PySide https://codereview.qt-project.org/c/pyside/pyside-setup/+/424628 (soon to be merged)