A python script to display 4 buttons on a TFT attached to a Pi and change text and colour when pressed

TFT_BasicButtons.py

import pygame
# Needs this to get the event types
from pygame.locals import *
import os
import logging
from time import sleep

log_format = '%(asctime)-6s: %(name)s - %(levelname)s - %(message)s'
console_handler = logging.StreamHandler()
console_handler.setFormatter(logging.Formatter(log_format))
logger = logging.getLogger()
logger.setLevel(logging.DEBUG)
logger.addHandler(console_handler)

#Colours
red = (255,0,0)
green = (0,255,0)
blue = (0,0,255)
black = (0,0,0)

display_width = 320
display_height = 240

# Assume all buttons of equal size (allow for a 5mm border all round to be added
button_dim = (0,0,120,80)
# define the centres for the buttons rather than top left
button_ctrs =[(85,65),(85,175),(235,65),(235,175)]
# I'm going to save the state of each button
button_state = [False , False, False, False]

# functions from https://pythonprogramming.net/displaying-text-pygame-screen/
# create a text object
def text_objects(text, font):
    textSurface = font.render(text, True, black)
    return textSurface, textSurface.get_rect()

# display text
def message_display(text,button):
    largeText = pygame.font.Font('freesansbold.ttf',75)
    TextSurf, TextRect = text_objects(text, largeText)
    TextRect.center = (button_ctrs[button])
    lcd.blit(TextSurf, TextRect)

# work out which quarter of the screen was pressed
def which_button ():
	pos = pygame.mouse.get_pos()
	#Find which quarter of the screen we're in
	x,y = pos
	button = 5
	if x < 160:
		if y < 120:
			button = 0
		else:
			button = 1
	else:
		if y < 120:
			button = 2
		else:
			button = 3

	return button

#########################
# Start doing things
#########################

# setup LCD screen
os.putenv('SDL_FBDEV', '/dev/fb1')
os.putenv('SDL_MOUSEDRV', 'TSLIB')
os.putenv('SDL_MOUSEDEV', '/dev/input/by-path/platform-20204000.spi-event')
#os.putenv('SDL_MOUSEDEV', '/dev/input/event0')

pygame.init()
pygame.mouse.set_visible(False)

# create a screen
lcd = pygame.display.set_mode((display_width, display_height))

# set up the initial screen
# Add a background
lcd.fill(red)

# build the array of rects with centers defined
buttons = []
for button in range (0,4):
	buttons.append(pygame.Rect(button_dim))
	buttons[button].center = button_ctrs[button]

#draw the buttons with a border
for button in buttons:
	# make the border by drawing a bigger rect first
	pygame.draw.rect(lcd, black, button.inflate(5,5), 0)
	pygame.draw.rect(lcd, blue, button, 0)
	message_display("off",buttons.index(button))

# update the whole screen as the borders are outside of the rects defined 
# so if we just updated those, the borders do not show.
pygame.display.flip()

# enclose loop in a try - catch to give a clean exit
try:
	print ("Press CTRL+C to exit")
	while True:
		# Scan touchscreen events
		for event in pygame.event.get():
			# Just use a button down event.
			if(event.type is MOUSEBUTTONDOWN):
				# which button was pressed
				but_pressed = which_button()
				# update the buttons state
				button_state[but_pressed] = not button_state[but_pressed]
				# update the display based on the state
				if button_state[but_pressed]:
					pygame.draw.rect(lcd, green, buttons[but_pressed], 0)
					message_display("on",but_pressed)
				else:
					pygame.draw.rect(lcd, blue, buttons[but_pressed], 0)
					message_display("off",but_pressed)
				# just update the pressed button rect	
				pygame.display.update(buttons[but_pressed])
				# put a sleep here to de-bounce
				sleep(0.2)
				# clear the queue of events that may have happened while we were sleeping
				pygame.event.clear()

except KeyboardInterrupt:
	# graceful exit (running interactively)
    print ("Goodbye.")