CODEWITHSUNDEEP
pythonfor-looppygametraceback
number1son10
number1son10

Reputation: 51

(IndexError: list index out of range) My for loop is giving me an error?

Here is my code:

import game, pygame, sys
from gameobjects import *
from imageloader import *




def main():
    screen = pygame.display.set_mode( (800, 600) )
    background = Background("images/Nebula1.bmp", screen.get_width(), screen.get_height())
    letter1 = pygame.image.load("1.bmp")
    letter2 = pygame.image.load("2.bmp")
    letter3 = pygame.image.load("3.bmp")
    letter4 = pygame.image.load("4.bmp")
    letter5 = pygame.image.load("5.bmp")
    letter6 = pygame.image.load("6.bmp")
    letter7 = pygame.image.load("7.bmp")
    letter8 = pygame.image.load("8.bmp")
    letter9 = pygame.image.load("9.bmp")
    letter10 = pygame.image.load("10.bmp")
    Letters = [letter1, letter2, letter3, letter4, letter5, letter6, letter7, letter8, letter9, letter10]
    letter = 0

    while True:
        for event in pygame.event.get():
            if event.type == pygame.QUIT:
                sys.exit()

        screen.blit(background.image, (0,0))

        for i in Letters:
            screen.blit( Letters[letter], (330 + 14 * letter, 190) )
            letter += 1


        pygame.display.flip()
All the items in the Letters list are pygame.Surfaces retrieved through using pygame.image.load(). Every time I run this code, I get an error that looks like this:

    Traceback (most recent call last):
      File "main.py", line 75, in <module>
        main()
      File "main.py", line 32, in main
        screen.blit( Letters[letter], ((330 + 14 * letter, 190)) )
    IndexError: list index out of range

Why is this happening? It seems perfectly valid to me. What am I doing wrong? What I want to do is paste each letter on the screen 14 pixels over from the last one, because each one is 14 pixels wide. Any help? (I am new to python so if I made a dumb mistake, forgive me.)

Upvotes: 1

Views: 4046

Answers (1)

agconti
agconti

Reputation: 18103

You have to set letter = 0 for each iteration. Because its outside of the while loop, letter is only set to 0 on initialization. Afterwards it throws an IndexError as on the second iteration of the for i in letters, as letter is now equal to the length of the letters because of the last iteration!

Use enumerate() to safety and easily increment:

for i,val in enumerate(Letters):
        screen.blit( Letters[i], (330 + 14 * letter, 190) )

or alternatively, include letter = 0 inside the while loop:

while True:
    for event in pygame.event.get():
        if event.type == pygame.QUIT:
            sys.exit()

    screen.blit(background.image, (0,0))

    letter = 0
    for i in Letters:
        screen.blit( Letters[i], (330 + 14 * letter, 190) )
        letter += 1

Upvotes: 2

Related Questions