Question

I’m currently trying to develop a game using pygame and I’m having some problems with some of my lists. Quite simple really, I want the shot to be deleted when going outside of the screen. My current code works perfect till I shoot more than one.

Current code:

#ManageShots
for i in range (len(ShotArray)):
    ShotArray[i].x += 10
    windowSurface.blit(ShotImage, ShotArray[i])
    if(ShotArray[i].x > WINDOWWIDTH):
        ShotArray.pop(i)

Error message:

ShotArray[i].x += 10
IndexError: list index out of range

Answer 1

Popping an item from the list moves everything after that item up one place. Thus, you end up with an index i that is easily outside of the range.

Remove items from your list after the loop, or loop over the list in reverse:

for shot in reversed(ShotArray):
    shot.x += 10
    windowSurface.blit(ShotImage, shot)
    if shot.x > WINDOWWIDTH:
        ShotArray.remove(shot)