Python-сообщество

 self.ui.mySpinBox.valueChanged.connect(self.spinboxChanged)
...
def spinboxChanged(self, value):
    print('new value of spinbox is:', value)

 import sys
from MyMainWindow import *
from PyQt5 import QtCore, QtGui, QtWidgets, Qt
from PyQt5.QtWidgets import QMessageBox
import strorint
def log_uncaught_exceptions(ex_cls, ex, tb):
    text = '{}: {}:\n'.format(ex_cls.__name__, ex)
    import traceback
    text += ''.join(traceback.format_tb(tb))
    print(text)
    QMessageBox.critical(None, 'Error', text)
    quit()
    
sys.excepthook = log_uncaught_exceptions
class MainWindow(QtWidgets.QMainWindow):
    def __init__(self, parent=None):
        QtWidgets.QWidget.__init__(self, parent)
        self.ui = Ui_MainWindow()
        self.ui.setupUi(self)
        self.statusBar().showMessage('Stop')
        self.ui.StartpushButton.clicked.connect(self.str)
        self.ui.StoppushButton_2.clicked.connect(self.Stop)
        self.ui.StartpushButton.clicked.connect(lambda: self.statusBar().showMessage(' запущен'))
        self.ui.StoppushButton_2.clicked.connect(lambda: self.statusBar().showMessage(' остановлен'))
        
        
    def str(self):
        
       pass
        
    def Stop(self):
        
        pass
        
if __name__=="__main__":
    app = QtWidgets.QApplication(sys.argv)
    myapp = MainWindow()
    myapp.show()
    sys.exit(app.exec_())

 ...
class MainWindow(QtWidgets.QMainWindow):
    ......     
    def getSomeVal(self):
        return self.ui.spinbox_name.value()
.....
myapp = MainWindow()
....
r = myapp.getSomeVal()

 ...
class MainWindow(QtWidgets.QMainWindow):
    def __init__(self, parent=None):
        ....
        self.ui.spinbox_name.valueChanged.connect(self.spinboxChanged)
    ...
    def spinboxChanged(self, value):
        print('new value of spinbox is:', value) # при изменении значения  спинбокса печатаем новое значение