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我正在尝试使用 PyGame 绘制图像，并从 Adafruit 复制了此代码。很奇怪，在我 Ctrl-C 之前屏幕上似乎什么都没有显示，此时它显示了图像。然后图像会一直停留在屏幕上，直到我再次按下 Ctrl-C。然后我收到以下消息：

Traceback（最近一次调用最后一次）：
文件“RaspiDisplay.py”，第 60 行，在 time.sleep
(10)
KeyboardInterrupt

这是怎么回事？顺便说一句，我在树莓派上通过 ssh 运行它，显示设置为 0（我的电视）

import os
import pygame
import time
import random

class pyscope :
    screen = None;

    def __init__(self):
        "Ininitializes a new pygame screen using the framebuffer"
        # Based on "Python GUI in Linux frame buffer"
        # http://www.karoltomala.com/blog/?p=679
        disp_no = os.getenv("DISPLAY")
        if disp_no:
            print "I'm running under X display = {0}".format(disp_no)

        # Check which frame buffer drivers are available
        # Start with fbcon since directfb hangs with composite output
        drivers = ['fbcon', 'directfb', 'svgalib']
        found = False
        for driver in drivers:
            # Make sure that SDL_VIDEODRIVER is set
            if not os.getenv('SDL_VIDEODRIVER'):
                os.putenv('SDL_VIDEODRIVER', driver)
            try:
                pygame.display.init()
            except pygame.error:
                print 'Driver: {0} failed.'.format(driver)
                continue
            found = True
            break

        if not found:
            raise Exception('No suitable video driver found!')

        size = (pygame.display.Info().current_w, pygame.display.Info().current_h)
        print "Framebuffer size: %d x %d" % (size[0], size[1])
        self.screen = pygame.display.set_mode(size, pygame.FULLSCREEN)
        # Clear the screen to start
        self.screen.fill((0, 0, 0))        
        # Initialise font support
        pygame.font.init()
        # Render the screen
        pygame.display.update()

    def __del__(self):
        "Destructor to make sure pygame shuts down, etc."

    def test(self):
        # Fill the screen with red (255, 0, 0)
        red = (255, 0, 0)
        self.screen.fill(red)
        # Update the display
        pygame.display.update()

# Create an instance of the PyScope class
scope = pyscope()
scope.test()
time.sleep(10)
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1 回答 1

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You're not running an event loop anywhere. Instead, you're just initializing everything, and then going to sleep for 10 seconds. During that 10 seconds, your code is doing nothing, because that's what you told it to do. That means no updating the screen, responding to mouse clicks, or anything else.

There are a few different ways to drive pygame, but the simplest is something like this:

while True:
    for event in pygame.event.get():
        if event.type == pygame.QUIT: sys.exit()
        # any other event handling you need
    # all the idle-time stuff you want to do each frame
    # usually ending with pygame.display.update() or .flip()

See the tutorial for more information.

As a side note, your initialization code has a bunch of problems. You iterate through three drivers, but you only set SDL_VIDEODRIVER once, so you're just trying 'fbcon' three times in a row. Also, you've got code to detect the X display, but you don't allow pygame/SDL to use X, so… whatever you were trying to do there, you're not doing it. Finally, you don't need a found flag in Python for loops; just use an else clause.

于 2013-06-02T05:14:23.410 回答