Why does pygame show a black window?

Question

Imports

#Imports
import pygame, sys, time, random
from pygame.locals import *

Display

pygame.init() #initializes pygame window
pygame.display.set_caption('Parkour') #titlebar caption

Bg=pygame.display.set_mode((800,600),0,32) #sets main surface

"""--------------------------------------------------------------------------"""

Event loop

gameActive = True
while gameActive:
    #print (event)
    for event in pygame.event.get():
        if event.type == pygame.QUIT:
            gameActive = False     
pygame.quit()
quit()

Background (ISSUE) Yeah I'm a beginner, but shouldn't this fill the screen then update it? Bg is true so it should constantly run right?

#Background
Bg = True
while Bg:
    screen.fill((0,0,255))
    pygame.display.flip()

Please put all your code snippets together to make a [mre] for others to run. — martineau, Jan 01 '20 at 02:35

Rabbid76 · Answer 1 · 2020-01-01T08:57:42.323

Furthermore the variable Bg is the Surface which is associated to the window:

Bg=pygame.display.set_mode((800,600),0,32) #sets main surface

Do not use the same variable name for a boolean state:

Bg = True

I recommend to change the name of the display surface (e.g. screen), because you've used this name in screen.fill((0,0,255)), too:

screen = pygame.display.set_mode((800,600),0,32) #sets main surface

Of course you have fill the background and to update the display in the main application loop. The main application has to

handle the events
clear the display
draw the scene
update the display

continuously in every frame.

e.g.:

#Imports
import pygame, sys, time, random
from pygame.locals import *

pygame.init() #initializes pygame window
pygame.display.set_caption('Parkour') #titlebar caption

screen = pygame.display.set_mode((800,600),0,32) #sets main surface

# main application loop
gameActive = True
while gameActive:

    # handle the events in the event loop
    for event in pygame.event.get():
        if event.type == pygame.QUIT:
            gameActive = False 

    # clear the display
    screen.fill((0,0,255))

    # draw the scene
    # [...] draw things here

    # update the display
    pygame.display.flip()

Why does pygame show a black window?

1 Answers1