Python 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.

 

[caleblee9]

Try this:

if cur_txt == 'Cheque' or cur_txt == 'Wire Transfer' or self.lineEdit_2.text().isEmpty():

Found here: https://forum.qt.io/topic/58489/check-qlineedit-empty

 

[djangocoder]

from PyQt5 import QtGui, QtWidgets

class NotEmptyValidator(QtGui.QValidator):
    def validate(self, text, pos):
        state = QtGui.QIntValidator.Acceptable if bool(text) else QtGui.QIntValidator.Invalid
        return state, text, pos

if __name__ == '__main__':
    import sys
    app = QtWidgets.QApplication(sys.argv)
    w = QtWidgets.QLineEdit("Hello World")
    validator = NotEmptyValidator(w)
    w.setValidator(validator)
    w.show()
    sys.exit(app.exec_())

Found here: https://codingtutz.com/how-to-avoid-null-or-empty-value-in-qlineedit-of-pyqt5/