Python – Age Calculator using PyQt

In this article we will see how we can create an age calculator using PyQt5.

PyQt5 is cross-platform GUI toolkit, a set of python bindings for Qt v5. One can develop an interactive desktop application with so much ease because of the tools and simplicity provided by this library. It has to be installed using command given below

pip install PyQt5

Below is how age calculator will look like

GUI Implementation Steps :
1. Create a head label for the title of the game, set its properties
2. Create a date of birth label, below this label create QDateEdit object to receive the date and set their properties
3. Create a given date label, below this label create QDateEdit object to receive the new date and set their properties
4. Create a push button which when pressed date is calculated
5. Create result label to show the result i.e calculated age

Back-End implementation Steps :
1. Add action to the first QDateEdit when date is changed
2. Inside the first date edit action get the date of second date edit and set this date as maximum date of the first date edit
3. Add action to the second date edit when date is changed
4. Inside the second date edit action get the date of the first date edit and set this date as minimum date of the second date edit
5. Set different date edits such that first date should be less than second date
6. Add action to the push button
7. Inside the push button action, get the dates from both the date edits and calculate the difference and show the difference to the screen with the help of result label

Below is the implementation

# importing libraries
from PyQt5.QtWidgets import *
from PyQt5 import QtCore, QtGui
from PyQt5.QtGui import *
from PyQt5.QtCore import *
import sys


class Window(QMainWindow):

    def __init__(self):
        super().__init__()

        # setting title
        self.setWindowTitle("Age calculator")

        # setting geometry
        self.setGeometry(100, 100, 500, 400)

        # calling method
        self.UiComponents()

        # showing all the widgets
        self.show()

    # method for components
    def UiComponents(self):

        # creating head label
        head = QLabel("Age Calculator", self)

        # setting geometry to the head
        head.setGeometry(100, 10, 300, 60)

        # font
        font = QFont('Times', 14)
        font.setBold(True)
        font.setItalic(True)
        font.setUnderline(True)

        # setting font to the head
        head.setFont(font)

        # setting alignment of the head
        head.setAlignment(Qt.AlignCenter)
        head.setStyleSheet("color : green;")


        # D.O.B label
        dob = QLabel("Date of Birth", self)

        # setting geometry
        dob.setGeometry(0, 80, 250, 50)

        # setting alignment and font
        dob.setAlignment(Qt.AlignCenter)
        dob.setFont(QFont('Times', 10))

        # given date label
        given = QLabel("Given Date", self)

        # setting geometry
        given.setGeometry(300, 80, 250, 50)

        # setting alignment and font
        given.setAlignment(Qt.AlignCenter)
        given.setFont(QFont('Times', 10))

        # creating a QDateEdit to get the d.o.b
        self.first = QDateEdit(self)

        # setting geometry
        self.first.setGeometry(25, 130, 200, 50)

        # setting font and alignment
        self.first.setAlignment(Qt.AlignCenter)
        self.first.setFont(QFont('Arial', 9))

        # adding action to the first
        # when date get change
        self.first.dateChanged.connect(self.first_action)

        # creating a QDateEdit to get the given date
        self.second = QDateEdit(self)

        # setting geometry
        self.second.setGeometry(275, 130, 200, 50)

        # setting font and alignment
        self.second.setAlignment(Qt.AlignCenter)
        self.second.setFont(QFont('Arial', 9))

        # adding action to the second
        # when date get change
        self.second.dateChanged.connect(self.second_action)

        # create a push button for calculate
        calculate = QPushButton("Calculate", self)

        # setting geometry to the push button
        calculate.setGeometry(200, 210, 100, 40)

        # setting color effect to the push button
        color = QGraphicsColorizeEffect()
        color.setColor(Qt.darkGreen)
        calculate.setGraphicsEffect(color)

        # adding action to the calculate button
        calculate.clicked.connect(self.find_age)

        # creating a result label to show the ans
        self.result = QLabel(self)

        # setting geometry
        self.result.setGeometry(50, 280, 400, 80)

        # setting style sheet and the font
        self.result.setAlignment(Qt.AlignCenter)
        self.result.setFont(QFont('Times', 12))

        # setting stylesheet
        self.result.setStyleSheet("QLabel"
                                  "{"
                                  "border : 2px solid black;"
                                  "background : lightgrey;"
                                  "}")

        # making label multi line
        self.result.setWordWrap(True)

        # set dates to the first and second
        self.first.setDate(QDate(2000, 1, 1))
        self.second.setDate(QDate(2020, 1, 1))


    # method called by the first date edit
    def first_action(self):

        # get the second date
        date = self.second.date()

        # set the maximum date in first
        self.first.setMaximumDate(date)

    # method called by the first date edit
    def second_action(self):

        # get the first date
        date = self.first.date()

        # set the maximum date in first
        self.second.setMinimumDate(date)


    # method called by the push button
    def find_age(self):

        # get the first age
        get_Qdate1 = self.first.date()
        birth_year = get_Qdate1.year()
        birth_month = get_Qdate1.month()
        birth_day = get_Qdate1.day()

        # get the second age
        get_Qdate2 = self.second.date()
        given_year = get_Qdate2.year()
        given_month = get_Qdate2.month()
        given_day = get_Qdate2.day()

        # if birth date is greater then given birth_month
        # then donot count this month and add 30 to the date so
        # as to subtract the date and get the remaining days
        month = [31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31]

        if (birth_day > given_day):
            given_month = given_month - 1
            given_day = given_day + month[birth_month - 1]

        # if birth month exceeds given month, then
        # donot count this year and add 12 to the
        # month so that we can subtract and find out
        # the difference
        if (birth_month > given_month):
            given_year = given_year - 1
            given_month = given_month + 12

        # calculate day, month, year
        calculated_day = given_day - birth_day
        calculated_month = given_month - birth_month
        calculated_year = given_year - birth_year

        # setting text to the result
        self.result.setText(str(calculated_day) + " Day(s), " + str(calculated_month)
                            + " Month(s), " + str(calculated_year) + " Year(s)")



    # create pyqt5 app
App = QApplication(sys.argv)

# create the instance of our Window
window = Window()

# start the app
sys.exit(App.exec())

Output :