how do i add play again for tkinter python? - python-3.x

Question

I can't find a source on how to add play again for my python code. I am currently using a snake game that i found on YouTube but I honestly am having trouble figuring this out.
github.com/Amfuhr/Snake-game.git
def game_over():
canvas.delete(ALL)
canvas.create_text(canvas.winfo_width()/2, canvas.winfo_height()/2,
font=('consolas',70), text="GAME OVER", fill="red", tag="gameover")
The full script:
#The tkinter package (“Tk interface”) is the standard Python interface to the Tcl/Tk GUI toolkit.
#Tkinter are available on most Unix platforms, including macOS, as well as on Windows systems.
from tkinter import *
import random
#box size, game speed, and color schemes
#classes for the game settings
GAME_WIDTH = 700
GAME_HEIGHT = 700
SPEED = 400
#Snake and food size
SPACE_SIZE = 50
BODY_PARTS = 3
#class for snake and food
#RGB for the color of the backgrund, snake, and food
SNAKE_COLOR = "white"
FOOD_COLOR = "blue"
BACKGROUND_COLOR = "#000000"
class Snake:
#set the body size of the snake, a list of square graphics
def __init__(self):
self.body_size = BODY_PARTS
self.coordinates = []
self.squares = []
#list of coordinates
for i in range(0, BODY_PARTS):
self.coordinates.append([0, 0])
for x, y in self.coordinates:
square = canvas.create_rectangle(x, y, x + SPACE_SIZE, y + SPACE_SIZE, fill=SNAKE_COLOR, tag="snake")
self.squares.append(square)
class Food:
def __init__(self):
#food is set into random location using the random module
#based on orientation. We use fill to set the food color
x = random.randint(0, (GAME_WIDTH / SPACE_SIZE)-1) * SPACE_SIZE
y = random.randint(0, (GAME_HEIGHT / SPACE_SIZE) - 1) * SPACE_SIZE
self.coordinates = [x, y]
canvas.create_oval(x, y, x + SPACE_SIZE, y + SPACE_SIZE, fill=FOOD_COLOR, tag="food")
def next_turn(snake, food):
#head of the snake and the direction of the snake movements
x, y = snake.coordinates[0]
if direction == "up":
y -= SPACE_SIZE
elif direction == "down":
y += SPACE_SIZE
elif direction == "left":
x -= SPACE_SIZE
elif direction == "right":
x += SPACE_SIZE
snake.coordinates.insert(0, (x, y))
square = canvas.create_rectangle(x, y, x + SPACE_SIZE, y + SPACE_SIZE, fill=SNAKE_COLOR)
snake.squares.insert(0, square)
if x == food.coordinates[0] and y == food.coordinates[1]:
global score
score += 1
label.config(text="Score:{}".format(score))
canvas.delete("food")
food = Food()
else:
del snake.coordinates[-1]
canvas.delete(snake.squares[-1])
del snake.squares[-1]
if check_collisions(snake):
game_over()
else:
window.after(SPEED, next_turn, snake, food)
def change_direction(new_direction):
global direction
if new_direction == 'left':
if direction != 'right':
direction = new_direction
elif new_direction == 'right':
if direction != 'left':
direction = new_direction
elif new_direction == 'up':
if direction != 'down':
direction = new_direction
elif new_direction == 'down':
if direction != 'up':
direction = new_direction
def check_collisions(snake):
x, y = snake.coordinates[0]
if x < 0 or x >= GAME_WIDTH:
return True
elif y < 0 or y >= GAME_HEIGHT:
return True
for body_part in snake.coordinates[1:]:
if x == body_part[0] and y == body_part[1]:
return True
return False
def game_over():
canvas.delete(ALL)
canvas.create_text(canvas.winfo_width()/2, canvas.winfo_height()/2,
font=('consolas',70), text="GAME OVER", fill="red", tag="gameover")
#Window sizing so it does not game
window = Tk()
window.title("Snake game")
window.resizable(False, False)
score = 0
direction = 'down'
#this is to show the score in a specific font size
label = Label(window, text="Score:{}".format(score), font=('consolas', 40))
label.pack()
#canvas sets the background and opens the window
canvas = Canvas(window, bg=BACKGROUND_COLOR, height=GAME_HEIGHT, width=GAME_WIDTH)
canvas.pack()
window.update()
window_width = window.winfo_width()
window_height = window.winfo_height()
screen_width = window.winfo_screenwidth()
screen_height = window.winfo_screenheight()
x = int((screen_width/2) - (window_width/2))
y = int((screen_height/2) - (window_height/2))
# Geometry method is used to set the dimensions of the
# Tkinter window and is used to set the position of the main
# window on the user’s desktop.
window.geometry(f"{window_width}x{window_height}+{x}+{y}")
window.bind('<Left>', lambda event: change_direction('left'))
window.bind('<Right>', lambda event: change_direction('right'))
window.bind('<Up>', lambda event: change_direction('up'))
window.bind('<Down>', lambda event: change_direction('down'))
snake = Snake()
food = Food()
next_turn(snake, food)
window.mainloop()

Answer 1

Think about it this way. Your app works upon running the first time around, and you just want to repeat, that behavior, (aka run that portion of the code again), once the initial game is over without having to restart the app.
This is precisely what functions are for.
The portion of your code that executes the game is just the last three lines of your script.
snake = Snake()
food = Food()
next_turn(snake, food)
So what you can do is stick those 3 lines into a function, and put the function call just before the mainloop call where the lines used to be.
def start_game(*arg):
canvas.delete(ALL)
snake = Snake()
food = Food()
next_turn()
start_game()
window.mainloop()
So now in order to restart the game, all you need to do is call the start_game function. Adding the canvas.delete(ALL) ensures that the "GAME OVER" message is removed before the new game starts.
Now all you need is a trigger. For this you can add a double-click signal on the canvas so that when it says "GAME OVER" all you need to do is double-click on the window and the new game starts. You can even add an instruction for the user.
To do this just add a window.bind call for the double-click action gesture:
window.bind('<Double-Button-1>', start_game)
Then to add the note to your "Game Over" message in your game_over function:
def game_over():
canvas.delete(ALL)
canvas.create_text(canvas.winfo_width()/2, canvas.winfo_height()/2,
font=('consolas',70), text="GAME OVER",
fill="red", tag="gameover")
canvas.create_text(canvas.winfo_width()/2, canvas.winfo_height()/1.8,
font=('consolas',20), text="double click for new game",
fill='green', tag='newgame')
And that should do it. This solution does create a new issue though, since there are no conditions on the new event binder, double clicking the screen will start a new game even if the current game is still ongoing.
I will leave this for you to try to solve. Or if you prefer you can use a different trigger.