pyqt学习

# -*- coding: utf-8 -*-
import sys
from PyQt5 import QtWidgets,QtCore,QtGui
from PyQt5.uic import loadUi

class MainWindow(QtWidgets.QMainWindow):
def __init__(self, parent=None):
super(MainWindow, self).__init__(parent)

loadUi('mainwindow.ui', self)

self.ConfirmButton.clicked.connect(self.valueChange)
self.ExitButton.clicked.connect(self.Exit)

def valueChange(self):
str = self.InputLine.text()

if str == "":
print ("inputline is empyt")
else:
print ("inputline = %s"%str)
newstr = self.reverseStr(str)

#print ("newstr = %s"%newstr)
self.OutputLine.setText(newstr)

def reverseStr(self,str):
newlist = list(str)
newlist.reverse()
#print (newlist)
newstr = "".join(newlist)
return newstr

def Exit(self):
QtWidgets.QApplication.quit()

if __name__ == '__main__':
print ("start...")
app = QtWidgets.QApplication(sys.argv)
mainwindow = MainWindow()
mainwindow.show()

sys.exit(app.exec_())