PyQt5 QLine setInputMask + setValidator IP address

Question

Problem to combine a setInputMask and setValidator IPv4 Address into a QlineEdit

I have a QLineEdit to set my IPv4 address. In the first time, I set my QLineEdit with setInputMask to have " . . . " In the second time, I'm using a Ip Validator to check if it's a IP address

The problem is when I'm using separately, it's working but together, I can't edit my QLineEdit...

self.lineEdit_IP = QtWidgets.QLineEdit(self.centralwidget)
self.lineEdit_IP.setGeometry(120,0,160,30)
self.lineEdit_IP.setStyleSheet("background-color: rgb(255, 255, 255);")
self.lineEdit_IP.setAlignment(QtCore.Qt.AlignHCenter)
self.lineEdit_IP.setInputMask("000.000.000.000")
#Set IP Validator
regexp = QtCore.QRegExp('^(25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?)(\.(25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?)){0,3}$')
validator = QtGui.QRegExpValidator(regexp)
self.lineEdit_IP.setValidator(validator)

Answer 1

Setting up a mask for QLine changes it's contents from empty to specified symbols. In your case "empty" QLine actually looks like "...". That's why regex failed. You could use your own overridden validator:

class IP4Validator(Qt.QValidator):
    def __init__(self, parent=None):
        super(IP4Validator, self).__init__(parent)

    def validate(self, address, pos):
        if not address:
            return Qt.QValidator.Acceptable, pos
        octets = address.split(".")
        size = len(octets)
        if size > 4:
            return Qt.QValidator.Invalid, pos
        emptyOctet = False
        for octet in octets:
            if not octet or octet == "___" or octet == "   ": # check for mask symbols
                emptyOctet = True
                continue
            try:
                value = int(str(octet).strip(' _')) # strip mask symbols
            except:
                return Qt.QValidator.Intermediate, pos
            if value < 0 or value > 255:
                return Qt.QValidator.Invalid, pos
        if size < 4 or emptyOctet:
            return Qt.QValidator.Intermediate, pos
        return Qt.QValidator.Acceptable, pos

and use it like this

    validator = IP4Validator()
    self.ipAddrLineEdit.setValidator(validator)

with masks like "000.000.000.000;_" or "000.000.000.000; " <--with whitespace at the end