单击按钮时未找到tkinter图像

Question

我有一个按钮的实例，它使用两个图像来表示处于打开或关闭状态的双向阀

两个图像的路径都有效，因为我可以用其中一个图像初始化按钮

我引用了这两个图像并将变量设置为全局变量，但仍然得到“\u tkinter.TclError:图像“vbon”不存在”

代码如下：

from tkinter import *
from PIL import Image, ImageTk

toggleA = 0
global vboncopy, vboffcopy, vbon, vboff
root = Tk()
root.title("ICP")
root.geometry('200x125')

def valve_A():
     global toggleA
     if toggleA == 0:
         toggleA = 1
         #vbon = ImageTk.PhotoImage(Image.open("/home/pi/mu_code/images/Black80x40VbuttonON.jpg"), master=root)
         ValveA['image'] = 'vbon'
         #ValveA.configure(image='vbon')
         #ValveA = Button(root, image=vbon, command = valve_A())        
     else:
         toggleA = 0
         #vboff = ImageTk.PhotoImage(Image.open("/home/pi/mu_code/images/Black80x40VbuttonOFF.jpg"), master=root)
         ValveA['image'] = 'vboff'
         #ValveA.configure(image='vboff')
         #ValveA = Button(root, image=vboff, command = valve_A())

global vboncopy, vboffcopy, vbon, vboff
vbon = ImageTk.PhotoImage(Image.open("/home/pi/mu_code/images/Black80x40VbuttonON.jpg"), master=root)
vboncopy = vbon
vboff = ImageTk.PhotoImage(Image.open("/home/pi/mu_code/images/Black80x40VbuttonOFF.jpg"), master=root)
vboffcopy = vboff

ValveA = Button(root, bd= -2, image=vboff, command = lambda: valve_A())
ValveA.grid(row=0, column=0, padx='12',pady='5')

root.mainloop()

以下是完整的错误消息：

Exception in Tkinter callback
Traceback (most recent call last):
  File "/usr/lib/python3.7/tkinter/__init__.py", line 1705, in __call__
    return self.func(*args)
  File "/home/pi/mu_code/StackOverflow.py", line 31, in <lambda>
    ValveA = Button(root, bd= -2, image=vboff, command = lambda: valve_A())
  File "/home/pi/mu_code/StackOverflow.py", line 15, in valve_A
    ValveA['image'] = 'vbon'
  File "/usr/lib/python3.7/tkinter/__init__.py", line 1492, in __setitem__
    self.configure({key: value})
  File "/usr/lib/python3.7/tkinter/__init__.py", line 1485, in configure
    return self._configure('configure', cnf, kw)
  File "/usr/lib/python3.7/tkinter/__init__.py", line 1476, in _configure
    self.tk.call(_flatten((self._w, cmd)) + self._options(cnf))
_tkinter.TclError: image "vbon" doesn't exist
Traceback (most recent call last):
  File "/home/pi/mu_code/StackOverflow.py", line 34, in <module>
    root.mainloop()
  File "/usr/lib/python3.7/tkinter/__init__.py", line 1283, in mainloop
    self.tk.mainloop(n)
KeyboardInterrupt
>>> 

我错过了什么？请帮忙

Answer 1

让我们看看这段代码：

ValveA['image'] = 'vbon'

它不是在做你认为它在做的事情。它试图将image选项设置为四字节字符串“vbon”。没有将其作为名称的图像

以下是您应该如何引用图像：

ValveA['image'] = vbon

---

FWIW、vboncopy和vboffcopy不是拷贝——它们只是同一图像的不同引用