在 Python Zelle 图形中实现多线程

Question

我正在创建一个使用 Zelle 的 graphics.py 在 window 中打开世界地图的程序。它有一个在地图上绘制点的功能，另一个功能是在这些点在屏幕上显示 1 秒后取消绘制这些点（绘制后存储在列表中）。我希望这些函数同时工作，但是当在线程中调用 addDots() 函数时，它不会在 window 中绘制点，它只是停止。这是我运行:

的模块

import thread
import threading
import time
import random
import sys
sys.path.append('..')
from Display import map
import tester
import datetime


dots = list(())

def deleteDots():
    while 1==1:
        tF = datetime.datetime.now()
        a = 0
        for i in range(len(dots)):
            tD = tF - dots[i-a][2]
            tD = int(str(tD)[5:7])
            if tD >= 1:
                map.deletePoint(dots[i-a][0],dots[i-a][1])
                dots.pop(i-a)
                a = a+1
def addDots():
    oldResponseCount = tester.getResponseCount()
    oldResponseCount = int(str(oldResponseCount))
    while 1==1:
        print(oldResponseCount)
        newResponseCount = tester.getResponseCount()
        newResponseCount = int(str(newResponseCount))
        print(newResponseCount)

       if(newResponseCount != oldResponseCount):
            difference = newResponseCount - oldResponseCount

            for i in range(difference):
                lat = random.randint(-90,90)
                long = random.randint(-180,180)
                map.drawPoint(lat,long)
                tI = datetime.datetime.now()
                dots.append([lat,long,tI])

       oldResponseCount = newResponseCount

if __name__ == '__main__':
    threading.Thread(target=addDots).start()
    threading.Thread(target=deleteDots).start()

这是在图形上绘制地图的地图模块 window 并包含绘制和删除点的功能：

from graphics import *
import math
import images
size = 0.6
Circles = list(())
win = GraphWin("My Window", 1920*size, 1080*size)
win.setBackground('blue')
images.test(size)
myImage = Image(Point(960*size,540*size), "../Display/temp.gif")

myImage.draw(win)
import time

def drawPoint(lat,long):
    x = int(long*5.3+960)*size
    y = int(lat*(-5.92)+540)*size
    pt = Point(x,y)
    cir = Circle(pt,5)
    cir.setFill(color_rgb(255,0,0))
    Circles.append([cir,x,y])
    cir.draw(win)

def deletePoint(lat,long): 
    x = int(long*5.3+960)*size
    y = int(lat*(-5.92)+540)*size
    for c in Circles:
        if c[1]==x and c[2]==y:
            c[0].undraw()

我应该怎么做？

Answer 1

有几个问题需要解决。首先，任何调用 tkinter 的 graphics.py 命令（即导致某些东西成为 drawn/undrawn 的命令）必须由主（主）线程发出。所以我们需要辅助线程向主线程传达绘图请求。

其次，您的两个辅助线程都在修改 Circles 和 dots 列表——您需要同步（锁定）对这些列表的访问，以便一次只有一个线程可以修改或迭代它们。

以下是我对您的代码进行的修改示例。我已经删除了地图和测试程序例程，因为我只是将点放在一个线程的 window 上，并在它们从另一个线程旧时删除它们：

from threading import Thread, Lock
from queue import Queue  # use for thread-safe communications
from random import randint
import time

from graphics import *

def drawPoint(lat, long):
    x = int(long * 5.3 + 960)
    y = int(lat * -5.92 + 540)

    point = Point(x, y)
    circle = Circle(point, 5)
    circle.setFill(color_rgb(255, 0, 0))

    circles_lock.acquire()
    circles.append(circle)
    circles_lock.release()

    actions.put((circle.draw, win))

def deletePoint(lat, long):
    global circles

    x = int(long * 5.3 + 960)
    y = int(lat * -5.92 + 540)

    keep_circles = []

    circles_lock.acquire()
    for circle in circles:
        center = circle.getCenter()

        if center.getX() == x and center.getY() == y:
            actions.put((circle.undraw,))
        else:
            keep_circles.append(circle)

    circles = keep_circles
    circles_lock.release()


def deleteDots():
    global dots

    while True:
        keep_dots = []

        dots_lock.acquire()
        now = time.time()

        for dot in dots:
            lat, long, then = dot

            if now - then >= 1.0:
                deletePoint(lat, long)
            else:
                keep_dots.append(dot)

        dots = keep_dots
        dots_lock.release()

        time.sleep(0.5)

def addDots():
    while True:
        lat = randint(-90, 90)
        long = randint(-180, 180)

        drawPoint(lat, long)

        dots_lock.acquire()
        dots.append((lat, long, time.time()))
        dots_lock.release()

        time.sleep(0.25)

win = GraphWin("My Window", 1920, 1080)

circles = []
circles_lock = Lock()

dots = []
dots_lock = Lock()

actions = Queue()

Thread(target=addDots, daemon=True).start()
Thread(target=deleteDots, daemon=True).start()

while True:
    if not actions.empty():
        action, *arguments = actions.get()
        action(*arguments)

    time.sleep(0.125)

在 Python Zelle 图形中实现多线程

Implement multithreading in Python Zelle graphics

python

multithreading

zelle-graphics