#https://www.pythonguis.com/tutorials/pyqt6-signals-slots-events/
import sys
from PyQt6.QtWidgets import QApplication, QMainWindow, QPushButton
class MainWindow(QMainWindow):
    def __init__(self):
        super().__init__()
        self.setWindowTitle("Moja aplikacija")
        self.gumb = QPushButton("Pritisni me!")
        self.gumb.clicked.connect(self.the_button_was_clicked)
        self.setCentralWidget(self.gumb)
    def the_button_was_clicked(self):
        self.gumb.setText("Ravnokar si pritisnil.")
        self.gumb.setEnabled(False)
        self.setWindowTitle("Pritisnil si")
aplikacija = QApplication(sys.argv)
okno = MainWindow()
okno.show()
aplikacija.exec()