Dark Artistry

import flet as ft
import datetime
import calendar
from calendar import HTMLCalendar
from dateutil import relativedelta

'''
FletCalendar in Python.

Flet does not have one so I needed to make my own
and I thought I would share.

Author: C. Nichols <mohawke@gmail.com>
License: WTFPL
    
WTFPL — Do What the Fuck You Want to Public License


Requirements: You need to install the following.

pip install flet

I suggest you use a Python virtual environment.
That will keep your system Python clean and make
it easier to manage you Flet project.

https://docs.python.org/3/library/venv.html 
'''

class FletCalendar(ft.UserControl):
    
    def __init__(self, page):
        super().__init__()
        
        self.page = page
        self.get_current_date()
        self.set_theme()
        
        # Init the container control.
        self.calendar_container = ft.Container(width=355, height=300,
                                          padding=ft.padding.all(2), 
                                          border=ft.border.all(2, self.border_color),
                                          border_radius=ft.border_radius.all(10),
                                          alignment=ft.alignment.bottom_center)
        self.build() # Build the calendar.
        self.output = ft.Text() # Add output control.  
    
    def get_current_date(self):
        '''Get the initial current date'''
        today = datetime.datetime.today()
        self.current_month = today.month
        self.current_day   = today.day
        self.current_year  = today.year 
    
    def selected_date(self, e):
        '''User selected date'''
        self.output.value = e.control.data
        self.output.update()
        #return e.control.data
        
    def set_current_date(self):
        '''Set the calendar to the current date.'''
        today = datetime.datetime.today()
        self.current_month = today.month
        self.current_day   = today.day
        self.current_year  = today.year 
        self.build()
        self.calendar_container.update()
        
    def get_next(self, e):
        '''Move to the next month.'''
        current = datetime.date(self.current_year, self.current_month, self.current_day) 
        add_month = relativedelta.relativedelta(months=1)
        next_month = current + add_month
        
        self.current_year = next_month.year
        self.current_month = next_month.month
        self.current_day = next_month.day
        self.build()
        self.calendar_container.update()
    
    def get_prev(self, e):
        '''Move to the previous month.'''
        current = datetime.date(self.current_year, self.current_month, self.current_day) 
        add_month = relativedelta.relativedelta(months=1)
        next_month = current - add_month
        self.current_year = next_month.year
        self.current_month = next_month.month
        self.current_day = next_month.day
        self.build()
        self.calendar_container.update()
        
    def get_calendar(self):
        '''Get the calendar from the calendar module.'''
        cal = HTMLCalendar()
        return cal.monthdayscalendar(self.current_year, self.current_month)
    
    def set_theme(self, border_color=ft.colors.PINK_700, 
                  text_color=ft.colors.PINK_50, 
                  current_day_color=ft.colors.PINK_700):
        self.border_color = border_color
        self.text_color = text_color
        self.current_day_color = current_day_color
    
    def build(self):
        '''Build the calendar for flet.'''
        current_calendar = self.get_calendar()
        
        str_date = '{0} {1}, {2}'.format(calendar.month_name[self.current_month], self.current_day, self.current_year)
        
        date_display = ft.Text(str_date, text_align='center', size=20, color=self.text_color)
        next_button = ft.Container( ft.Text('>', text_align='right', size=20, color=self.text_color), on_click=self.get_next )
        div = ft.Divider(height=1, thickness=2.0, color=self.border_color)
        prev_button = ft.Container( ft.Text('<', text_align='left', size=20, color=self.text_color), on_click=self.get_prev )
        
        calendar_column = ft.Column([ft.Row([prev_button, date_display, next_button], alignment=ft.MainAxisAlignment.SPACE_EVENLY, 
                                            vertical_alignment=ft.CrossAxisAlignment.CENTER, height=40, expand=False), div], 
                                    spacing=2, width=355, height=330, alignment=ft.MainAxisAlignment.START, expand=False)
        # Loop weeks and add row.
        for week in current_calendar:
            week_row = ft.Row(alignment=ft.MainAxisAlignment.CENTER)
            # Loop days and add days to row.
            for day in week:
                if day > 0:
                    is_current_day_font = ft.FontWeight.W_300
                    is_current_day_bg = ft.colors.TRANSPARENT
                    display_day = str(day)
                    if len(str(display_day)) == 1: display_day = '0%s' % display_day
                    if day == self.current_day: 
                        is_current_day_font = ft.FontWeight.BOLD
                        is_current_day_bg = self.current_day_color
                        
                    day_button = ft.Container(content=ft.Text(str(display_day), weight=is_current_day_font, color=self.text_color), 
                                              on_click=self.selected_date, data=(self.current_month, day, self.current_year), 
                                              width=40, height=40, ink=True, alignment=ft.alignment.center,
                                              border_radius=ft.border_radius.all(10),
                                              bgcolor=is_current_day_bg)
                else:
                    day_button = ft.Container(width=40, height=40, border_radius=ft.border_radius.all(10))
                    
                week_row.controls.append(day_button)
                
            # Add the weeks to the main column.
            calendar_column.controls.append(week_row)
        # Add column to our page container. 
        self.calendar_container.content = calendar_column
        return self.calendar_container
                
def main(page: ft.Page):    
    
    page.theme = ft.theme.Theme(color_scheme_seed=ft.colors.PINK)
    page.dark_theme = ft.theme.Theme(color_scheme_seed=ft.colors.PINK) 

    # Instantiate the FletCalendar class.
    mycal = FletCalendar(page)
    
    # Add to our application.
    page.add(mycal, mycal.output)

    page.update()
    
ft.app(target=main)