Tkinter'绑定'与'画布'和线程ValueError [英] Tkinter 'bind' with 'canvas' and threading ValueError
问题描述
起初，我认为这是一个可以在此中解决的问题不是重复的内容在下方略有下降。）
At first, I thought this was an issue that could be solved in this post that I found. However, I have tried to implement the after method but it seems to not work. (More info on how I believe my question is different and not a duplicate is a little further down below.)
当试图将 button-1 绑定到函数 callback ，该函数是从其他线程运行的。有问题的代码在这里
The error is formed when trying to bind button-1 to the function callback, which is running from a different thread than everything else. The code in question is here
def callback(event):
print(event) #This function normally changes playerY, however it prints the event for debugging purpose.
def drawPlayer():
global playerY, playerY2
player = canvas.create_oval(50,50,100,100,fill="yellow",outline="black")
while True:
canvas.coords(player,(50,50,100,100)) #This would usually use playerY and playerY2 but for debugging it does not.
playerY += 0.0018
playerY2 += 0.0018
root.bind("<Button-1>",callback)
thread2 = Thread(target=drawPlayer)
thread2.start()
显然，诸如root，playerY，playerY2等是已经定义，但我不会粘贴整个代码。
Obviously things such as root, playerY, playerY2 etc are already definded but I am not going to paste my whole code.
单击按钮1会产生以下回溯
When button 1 is clicked this will produce the following traceback
Exception in thread Thread-2:
Traceback (most recent call last):
File "C:\Python33\lib\threading.py", line 637, in _bootstrap_inner
self.run()
File "C:\Python33\lib\threading.py", line 594, in run
self._target(*self._args, **self._kwargs)
File "C:\Users\Harvey\Documents\School Work\Computer Science\Tkinter\tkinterFallpyBird.py", line 58, in drawPlayer
canvas.coords(player,(50,50,100,100))
File "C:\Python33\lib\tkinter\__init__.py", line 2299, in coords
self.tk.call((self._w, 'coords') + args))]
File "C:\Python33\lib\tkinter\__init__.py", line 2297, in <listcomp>
return [getdouble(x) for x in
ValueError: could not convert string to float: 'None'
另一个线程告诉我要使用'after'方法来解决这个问题。为此，我尝试了以下操作：
The other thread tells me to solve this by using the 'after' method. To do this I tried:
def drawPlayer():
global playerY, playerY2,player
canvas.coords(player,(playerY,50,playerY2,100))
playerY += 0.0018
playerY2 += 0.0018
root.after(1,drawPlayer)
root.bind("<Button-1>",callback)
player = canvas.create_oval(50,50,100,100,fill="yellow",outline="black")
drawPlayer()
root.mainloop()
我的函数 drawPlayer 需要重复调用，因此线程版本中的while循环。我觉得这就是我的问题与我一开始所链接的问题有何不同。我试图在 root.after（）调用中使用 0 ，但这只会导致调用后的代码 drawPlayer（）未运行。
My function drawPlayer needs to be called repeatedly, hence the while loop in the threaded version. I feel this is how my question differs from the one I linked at the start. I tried to use 0 in the root.after() call, but that just leads to code after the call of drawPlayer() not being run.
除非，我缺少与
旁注：我意识到我不应该在tkinter上开发一款游戏，尤其是需要同时进行多件事的游戏。但是，我在学校正在做这个事情，我想使用的模块（Pygame或Pyglet）无法下载，仅仅是为了我做一个没有真正目的的游戏。如果我可以使用tkinter以外的其他方式，我可能会使用。感谢您的帮助。
Unless, I am missing something to do with the after method, or the threading module, I don't understand how I can fix this issue.
Side note: I realise I should not be making a game in tkinter, especially one that requires multiple things to be happening at once. However, I am doing this at school and the modules I would like to use (Pygame or Pyglet) cannot be downloaded just for me to make a game that has no real purpose. If I could use something other than tkinter I probably would. Thank you for your help.
推荐答案
在版本之后尝试，但再添加 0.0018 到 playerY 和 playerY2 。
尝试至少 1
工作示例：
from Tkinter import *
root = Tk()
canvas = Canvas(root)
canvas.pack()
playerY = 50
playerY2 = 100
def drawPlayer():
global playerY, playerY2,player
canvas.coords(player,(playerY,50,playerY2,100))
playerY += 1
playerY2 += 1
root.after(10,drawPlayer)
#root.bind("<Button-1>",callback)
player = canvas.create_oval(50,50,100,100,fill="yellow",outline="black")
drawPlayer()
root.mainloop()
这篇关于Tkinter'绑定'与'画布'和线程ValueError的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！
