Python tk.Label函數內部失敗

Question

3天前我開始學習Python，所以我是一個新手。 我想要的是選擇一個目錄並顯示其中的圖像。 當tk.Label是功能外「點擊」它工作正常，但內部功能「點擊」它拋出：

Exception in Tkinter callback 
Traceback (most recent call last): 
    File "C:\Users\*\AppData\Local\Programs\Python\Python35-32\lib\tkinter\__init__.py", line 1549, in __call__ 
    return self.func(*args) 
    File "C:/Users/*/PycharmProjects/first/app.py", line 90, in click 
    tk.Label(gui, image=tk_image).grid(row=1, column=0) # THIS LINE FAILED 
    File "C:\Users\*\AppData\Local\Programs\Python\Python35-32\lib\tkinter\__init__.py", line 2605, in __init__ 
    Widget.__init__(self, master, 'label', cnf, kw) 
    File "C:\Users\*\AppData\Local\Programs\Python\Python35-32\lib\tkinter\__init__.py", line 2131, in __init__ 
    BaseWidget._setup(self, master, cnf) 
    File "C:\Users\*\AppData\Local\Programs\Python\Python35-32\lib\tkinter\__init__.py", line 2109, in _setup 
    self.tk = master.tk 
AttributeError: 'str' object has no attribute 'tk' 

可以請人解釋一下嗎？這是到目前爲止我的代碼：

import tkinter as tk 
from tkinter import Tk 
from tkinter import Label 
from tkinter import Button 
# from tkinter import Image 
# from tkinter import PhotoImage # conflict 
# from tkinter import Frame 
from tkinter import Menu 
from tkinter import StringVar 
# from tkinter import * 
import tkinter.messagebox as mb 
import tkinter.filedialog as fd 
import getpass 
import os 
# import fnmatch 
from PIL import Image, ImageTk 
gui = Tk() 
user = getpass.getuser() 

gui.title('Project') 
gui.configure(background='#4D4D4D') # top level styling 
gui.geometry('800x400') # specify root window size and position 

def about(): 
    mb.showinfo("About", "Line\nLine\nLine") 

def help_box(): 
    mb.showinfo("Help", "Sorry, we can\'t help you at this moment", icon='question') 

def exit_editor(): 
    if mb.askokcancel("Quit", "Do you really want to quit?"): 
     gui.destroy() 

# Disabled for testing 
# gui.protocol('WM_DELETE_WINDOW', exit_editor) # override close button and redirect to exit_editor 

menubar = Menu(gui) 

# File menu,for open,save,save as and quit 
filemenu = Menu(menubar, tearoff=0) 
filemenu.add_command(label="Exit", accelerator='Alt+F4', command=exit_editor) 
menubar.add_cascade(label="File", menu=filemenu) 

# About menu - Aboutus, Help 
aboutmenu = Menu(menubar, tearoff=0) 
aboutmenu.add_command(label="About", command=about) 
aboutmenu.add_cascade(label="Help", command=help_box) 
menubar.add_cascade(label="About", menu=aboutmenu) 

# Returning defined setting for widget 
gui.config(menu=menubar) 

browseLabel = StringVar() 
browseLabel.set("Selecteer een map: ") 

def click(): 
    ext = ['.jpg', '.JPG', '.jpeg', '.JPEG'] 
    matches = [] 
    path = fd.askdirectory(initialdir='C:/Users/%s' % user) 
    if path != "": 
     browseLabel.set(path) 

    for gui, dirs, files in os.walk(path): 
     for file in files: 
      if file.endswith(tuple(ext)): 
       matches.append(os.path.join(gui, file)) 
       print(file) 

    # THE SAME CODE FAILES INSIDE FUNCTION 

    img = "C:/Foto's\\P5270026.JPG" 
    size = 100, 100 
    pil_image = Image.open(img) 
    pil_image.thumbnail(size, Image.ANTIALIAS) 
    tk_image = ImageTk.PhotoImage(pil_image) 
    # tk.Label(gui, image=tk_image).grid(row=1, column=0) # THIS LINE FAILED 

    for img in matches: 
     print("Match is %r" % img) 


# THIS CODE WORKS OUTSIDE FUNCTION 

# img = "C:/Foto's\\P5270026.JPG" 
# size = 100, 100 
# pil_image = Image.open(img) 
# pil_image.thumbnail(size, Image.ANTIALIAS) 
# tk_image = ImageTk.PhotoImage(pil_image) 
# tk.Label(gui, image=tk_image, bg='brown').grid(row=1, column=0) 

Label(gui, textvariable=browseLabel, bg="#4D4D4D", fg="#ffffff").grid(row=0, column=0, sticky='e') 
Button(gui, text="Bladeren", command=click).grid(row=0, column=1, padx=2, pady=2, sticky='w', columnspan=9) 

gui.mainloop() 

Answer 1

您有一個名爲gui一個全局變量保持到根窗口的引用。在你的函數中，你重用gui作爲局部變量來包含一個字符串。不要爲了兩個不同的目的而使用相同的變量名稱。