How to avoid Null or empty value in QLineedit of Pyqt5

[Lalremruata]

I tried to validate the QLineedit not to be empty without success.

I did

validator = QRegExpValidator(QRegExp(r'[0-9]+'))
self.lineEdit_2.setValidator(validator)

it is working.

But

def temp_var(self, text):
cur_txt = text
if cur_txt == 'Cheque' or cur_txt == 'Wire Transfer' or self.lineEdit_2.text() == "":
self.groupBox_3.show()
self.pushButton_7.hide()
self.pushButton_7.setEnabled(False)

else:
self.groupBox_3.hide()
self.pushButton_7.show()
self.pushButton_7.setEnabled(True)

all works fine but the pushbutton is always enabled even the self.lineEdit_2 is empty. I request your help. (I am a self-learner and could not find solution in the web.

 

[アノ・化け物]

Putting PyQT in your thread title would've been nice.

Anyway, add a breakpoint and watcher to your lineEdit's strings and look at it's value compared to it's data type.
Report here your result.