python - PyQt run time issue

Question

I want my code to run by showing the qtwidget and then running the forloop, but it runs the forloop then shows my widget to me. Why is this?

class tes(QWidget):

    def __init__(self):
        super(tes, self).__init__()
        self.initUI()
        for i in range (1000000):
            print("s")

    def initUI(self):
        t = QTableWidget(8,8,self)        
        self.show()
        self.resize(1000,1000)
        t.setGeometry(0,0,500,500)
        t.show()

def main():
    app = QApplication(sys.argv)
    t = tes()
    sys.exit(app.exec_())

if __name__ == "__main__":
    main()

Answer 1

Add QApplication.processEvents() before loop. Your widget will be shown, but unresponsive. To make application responsive, add processEvents() calls to some steps of your loop.

Example:

def __init__(self):
    super(tes, self).__init__()
    self.initUI()
    QApplication.processEvents()
    for i in range (1000000):
        if not i % 3:  # let application process events each 3 steps.
            QApplication.processEvents()
        print("s")