import sys
from PyQt5 import QtWidgets as qtw
from PyQt5 import QtGui as qtg
class InventoryNumberValidator(qtg.QValidator):
"""Validates an inventory number in the format XX-999-9999X
X is an uppercase letter from A to Z excluding O and I.
9 is any digit from 0 to 9.
"""
valid_letters = 'ABCDEFGHJKLMNPQRSTUVWXYZ'
def validate(self, string, index):
# one approach is to break the string into segments
# and test each segment for proper content
state = qtg.QValidator.Acceptable
seg1 = string[0:2]
dash1 = string[2:3]
seg2 = string[3:6]
dash2 = string[6:7]
seg3 = string[7:11]
seg4 = string[11:12]
if not all([char in self.valid_letters for char in seg1 + seg4]):
state = qtg.QValidator.Invalid
elif not all([char.isdigit() for char in seg2 + seg3]):
state = qtg.QValidator.Invalid
elif not all([char == '-' for char in dash1 + dash2]):
state = qtg.QValidator.Invalid
elif len(string) > 12:
state = qtg.QValidator.Invalid
elif not all([seg1, dash1, seg2, dash2, seg3, seg4]):
state = qtg.QValidator.Intermediate
return (state, string, index)
class MainWindow(qtw.QWidget):
def __init__(self):
"""MainWindow constructor.
This widget will be our main window.
We'll define all the UI components in here.
"""
super().__init__()
# Main UI code goes here
self.setLayout(qtw.QVBoxLayout())
inventory_number = qtw.QLineEdit()
inventory_number.setValidator(InventoryNumberValidator())
self.layout().addWidget(inventory_number)
# End main UI code
self.show()
if __name__ == '__main__':
app = qtw.QApplication(sys.argv)
# it's required to save a reference to MainWindow.
# if it goes out of scope, it will be destroyed.
mw = MainWindow()
sys.exit(app.exec())
