My program will run, but the K_RIGHT command will not work

Question

The screen pops up with the green rectangle but I can't move it. I don't understand why it won't work. any help would be highly appreciated!

import pygame
pygame.init()
width=1800
height=900
red=(255,0,0)
green=(0,255,0)
blue=(0,0,255)
white=(0,0,0)
black=(255,255,255)
x=800
y=150

running = True

def main():
    global running, screen, x, y

    screen = pygame.display.set_mode((width,height))
    pygame.draw.rect(screen, green,(x,y,100,300))
    pygame.display.update()
    while running:
        ev = pygame.event.get()
        for event in ev:
            if event.type==pygame.KEYDOWN:
                if event.type==pygame.K_RIGHT:
                    x+=20
                    pygame.display.update()
            if event.type==pygame.QUIT:
                pygame.quit()
                exit()
    pygame.display.update()
                
                
main()

You have tp draw the object in the application not just before the application loop. See [Why is my PyGame application not running at all?](https://stackoverflow.com/questions/65264616/why-is-my-pygame-application-not-running-at-all/65264742#65264742) — Rabbid76, Jul 23 '22 at 10:19
You're checking for `pygame.K_RIGHT` in the wrong attribute - you already know what `event.type` is (it's `pygame.KEYDOWN`), the specific key is going to be something like `event.key`. — jasonharper, Jul 25 '22 at 04:00

score 0 · Answer 1 · answered Jul 25 '22 at 04:55

You have to draw the object in the application not just before the application loop. See My program will run, but the K_RIGHT command will not work:

import pygame

pygame.init()

width, height = 1800, 900
x, y = 800, 150

def main():
    global running, screen, x, y

    screen = pygame.display.set_mode((width,height))
    clock = pygame.time.Clock()
    running = True

    while running:
        clock.tick(100)
        ev = pygame.event.get()
        for event in ev:
            if event.type==pygame.QUIT:
                running = False
            if event.type==pygame.KEYDOWN:
                if event.type==pygame.K_RIGHT:
                    x+=20
                
        screen.fill("black")
        pygame.draw.rect(screen, "green", (x,y,100,300))
        pygame.display.update()

    pygame.quit()
    exit()
                                
main()

The typical PyGame application loop has to:

handle the events by calling either pygame.event.pump() or pygame.event.get().
update the game states and positions of objects dependent on the input events and time (respectively frames)
clear the entire display or draw the background
draw the entire scene (blit all the objects)
update the display by calling either pygame.display.update() or pygame.display.flip()
limit frames per second to limit CPU usage with pygame.time.Clock.tick

My program will run, but the K_RIGHT command will not work

1 Answers1