def openMainWindow(self): # Test connection result = self.ftp.connect() if result.isSuccess: username = self.accountInput.text() passwd = self.passwdInput.text() result = self.ftp.login(username=username, passwd=passwd) if result.isSuccess: mainWindow = Ui_mainWindow(parent=self, ftp=self.ftp) print("mainWindow!") mainWindow.resize(1600,2200) mainWindow.show() else: QtWidgets.QMessageBox.warning(self, 'Warning', "Wrong username or password", QtWidgets.QMessageBox.Yes) else: QtWidgets.QMessageBox.warning(self, 'Warning', "Connection refused", QtWidgets.QMessageBox.Yes)