python - 我的条目的 stringvar 无法正常工作

Question

我有以下问题：我有一张表格，其中记录了需要哪个标签的文章。更改条目时应自动更新所需的标签。我在数据框中查找文章编号，然后将需要的标签作为图片返回。

出于某种原因，它只能工作一次，并且只有当我输入复制并粘贴正确的文章编号时。在第一次之后总是将 exept 值设置为我的变量。

我也不明白 *args 作为我的 search_label 函数的输入的含义。但是没有它，我在输入字段中输入内容后立即给了我错误：

Exception in Tkinter callback
Traceback (most recent call last):
  File "C:\Python\Python_3.9.1\lib\tkinter\__init__.py", line 1884, in __call__
    return self.func(*args)
TypeError: search_label() takes 0 positional arguments but 3 were given

from multiprocessing import Process
import tkinter as tk
import pandas as pd
from PIL import ImageTk, Image
import os
import tkinter.messagebox as tkmb



def display_img(img_src):
    global img
    img = Image.open(img_src)
    'size of the picture'
    width_hight = 180
    img = img.resize((width_hight, width_hight))
    img = ImageTk.PhotoImage(img)
    panel = tk.Label(root, image=img, bd=0)
    'place in the middle of the window'
    panel.place(x=width / 2 - width_hight / 2, y=row3)

def search_label(*args):

    try:
        artikel = entry_var.get()
        artikel = str(artikel).upper()
        print('entry= ', artikel)
        #Needed cols of Excelfile
        cols = ['Nr_','Reinigungsmittel']
        global df
        df = pd.DataFrame(df, columns=cols)
        #For some reason there are always spaces at the end of the artikel in the dataframe
        #remove spaces
        df['Nr_'] = df['Nr_'].str.strip()
        df.to_csv('Reinigungsmittel.csv', sep= ";", encoding='utf-8-sig')
        df = df.set_index('Nr_')
        #filter the dataframe only for artikel number
        print('df:')
        print(df)
        #make entry capital letters

        df_reinigungsmittel = df.loc[[artikel]]
        #get only the cleanning article
        cleaning_article = str(df_reinigungsmittel.iloc[0][0])
        print('ergebnis:')

        print(cleaning_article)
        cleaning_article = str(cleaning_article).strip()
    except:
        cleaning_article = 'label search failed'
    evaluation(cleaning_article)

def evaluation(cleaning_article):
    print('input evaluation:',cleaning_article)
    if cleaning_article == 'CMETHANOL':
        cleaning_article = 'rot.png'
    elif cleaning_article == 'CPROPANOL2':
        cleaning_article = 'gruen.png'
    elif cleaning_article == 'CPROPANOL':
        cleaning_article = 'blau.png'
    else:
        cleaning_article = 'non.png'
    print(cleaning_article)
    display_img(cleaning_article)


#load dataframe when program is opend, so the dataframe doent' need to be loaded for each search
datasource = r'C:\Arbeit\scripte\Reinigungslabel\Reinigungslabel.xlsx'
datasource_csv = r'C:\Arbeit\scripte\Reinigungslabel\Reinigungsmittel.csv'
#df = pd.read_excel(datasource)
df = pd.read_csv(datasource_csv, sep =';')

# Window and layout settings
hight = 270
width = 250

column_space = 5
column1 = 10
width_column1 = width - 20

#start value of cleaning_article
cleaning_article = 'non.png'

hight_row = 30
space_row = 5
row1 = 10
row2 = row1 + hight_row + space_row
row3 = row2 + hight_row + space_row


root = tk.Tk()
entry_var = tk.StringVar()
entry_var.trace('w',search_label)

print(df)
root.title("Reinigungs Label V1.0")

# get screen width and height
# width of the screen
ws = root.winfo_screenwidth()
# height of the screen
hs = root.winfo_screenheight()

# calculate x and y coordinates for the Tk root window
x = ws - (1.05 * width)
y = 30
root.geometry('%dx%d+%d+%d' % (width, hight, x, y))
root.configure(bg='black', bd=0)
Canvas = tk.Canvas(root, height=hight, width=width).place()

frame_artikel = tk.Frame(root, bg = 'black')
frame_artikel.place(x=column1, y=row1, width=width_column1, height=hight_row)

entry_artikel = tk.Entry(frame_artikel, textvariable=entry_var, font=20)
entry_artikel.focus()
entry_artikel.place(relwidth=1, relheight=1)


root.mainloop()

标签： pythonpython-3.xtkintertkinter-entry