在Pygame中随机发声

Question

im making a basic pygame and I was wondering if anyone can help me out

so after a certain amount of time a power-up scrolls down the screen but I cant get it to work

here is the method im using:

def random_event(self):
    self.force_img_r = self.force_img.get_bounding_rect()
    self.rnd_x = random.randint(5,315)
    self.force_img_r.x = self.rnd_x
    self.force_img_r.y += 3
    screen.blit(self.force_img,(self.rnd_x, self.force_img_r.y))

all its doing is the image is blinking for a split second then nothing

can anyone tell me why its not working!?

Answer 1

In pygame you usually have a main loop that cleans the screen on every iteration, that's probably why you only see a blink, you draw and in the next loop you clean again.

To work arround this, in pygame events should only update game state, and draw the screen on every loop according to the current state.

Some pseudocode:

# Main Loop
while True:

    # Process events
    #   -> Update game state

    # Clean screen
    # Draw current state to the screen

    # Update or flip display

    # Keep framerate (clock.Tick())

You can call external classes/methods/functions, but you should always keep this structure at the main loop.