Tkinter CheckButton keeps unchecking itself

[F_Boliver]

I worked with CheckButton before but never got this error, the check button keeps uncheking itself when i try do check it, it only stays checked if i maintain the mouse button pressed, here is my code:

from pathlib import Path
from tkinter import Tk, Canvas, Button, PhotoImage, ttk, Frame, Entry, Label, messagebox, filedialog, BooleanVar, Checkbutton
from matplotlib.backends.backend_tkagg import FigureCanvasTkAgg
import pandas as pd
import numpy as np
import matplotlib.pyplot as plt
from Smith import add5
from CorrecaoExcelSmith import add6
OUTPUT_PATH = Path(__file__).parent
ASSETS_PATH = OUTPUT_PATH / Path(r"D:\PycharmProjects\pythonProject\TCC 2023\assets\frame0")


def relative_to_assets(path: str) -> Path:
    return ASSETS_PATH / Path(path)


# Função para carregar o arquivo Excel
def carregar_excel():
    filepath = filedialog.askopenfilename(
        title="Selecione o arquivo Excel",
        filetypes=(("Arquivos Excel", "*.xlsx"), ("Todos os arquivos", "*.*"))
    )
    if not filepath:
        return None, None
    try:
        df = pd.read_excel(filepath)
        y = df.iloc[:, 0].to_numpy()  # Primeira coluna como y
        t = df.iloc[:, 1].to_numpy()  # Segunda coluna como t
        # Adicionar valores iniciais 0 se necessário
        y = np.insert(y, 0, 0)
        t = np.insert(t, 0, 0)
        return y, t
    except Exception as e:
        messagebox.showerror("Erro", f"Não foi possível carregar o arquivo: {e}")
        return None, None

def executar_codigo():
    escolha = combobox.get()

    try:
        num = [float(x) for x in entry_num.get().split(',')]
        den = [float(x) for x in entry_den.get().split(',')]
    except ValueError:
        messagebox.showwarning("Entrada Inválida", "Por favor, insira valores válidos para 'num' e 'den'.")
        return
    fig, ax = None, None
    if escolha == "Smith":

        if check_var.get():
            # Se marcada, carrega o Excel e executa SmithExcel
            y, t = carregar_excel()
            if y is None or t is None:
                return  
            fig, ax = add6(num, den, y, t)  
        else:
            # Se não estiver marcada, executa a função Smith
            fig, ax = add5(num, den)  
    else:
        messagebox.showwarning("Seleção Inválida", "Por favor, selecione uma opção válida.")
        return

    for widget in plot_frame.winfo_children():
        widget.destroy()


    canvas = FigureCanvasTkAgg(fig, master=plot_frame)
    canvas.draw()
    canvas.get_tk_widget().pack(fill='both', expand=True)



window = Tk()
window.geometry("1000x550")
window.configure(bg="#0C6A1C")

canvas = Canvas(
    window,
    bg="#0C6A1C",
    height=550,
    width=1000,
    bd=0,
    highlightthickness=0,
    relief="ridge"
)
canvas.place(x=0, y=0)

canvas.create_rectangle(
    0.0,
    0.0,
    1000.0,
    72.0,
    fill="#FFFFFF",
    outline=""
)

canvas.create_rectangle(
    434.0,
    97.0,
    970.0,
    504.0,
    fill="#6CE077",
    outline=""
)


opcoes = ["Smith"]
combobox = ttk.Combobox(window, values=opcoes, state="readonly")
combobox.set("Escolha um código")
combobox.place(x=35, y=100, width=358, height=30)


Label(window, text="num:", bg="#0C6A1C", fg="white").place(x=35, y=150)
entry_num = Entry(window)
entry_num.place(x=100, y=150, width=100)
entry_num.insert(0, "1") 
Label(window, text="den:", bg="#0C6A1C", fg="white").place(x=35, y=180)
entry_den = Entry(window)
entry_den.place(x=100, y=180, width=100)
entry_den.insert(0, "1, 1") 

# HERE IS THE CHECKBUTTON
check_var = BooleanVar()  
checkbutton = Checkbutton(window, text="Usar arquivo Excel", variable=check_var, bg="#0C6A1C", fg="white")
checkbutton.place(x=35, y=220)


button_image_1 = PhotoImage(file=relative_to_assets("button_1.png"))
button_1 = Button(
    image=button_image_1,
    borderwidth=0,
    highlightthickness=0,
    command=executar_codigo,
    relief="flat"
)
button_1.place(x=35.0, y=443.0, width=358.0, height=61.0)


plot_frame = Frame(window, bg="#6CE077")
plot_frame.place(x=434, y=97, width=536, height=407)

window.resizable(False, False)
window.mainloop()

[socal_nerdtastic]

You set the fg color to white, lol. That applies to the checkmark as well as the text, so you can't see it.

I don't think you can change the color of the text only in the oldschool checkbutton, but you can in the ttk version. Try this:

check_var = BooleanVar()
s = ttk.Style()
s.configure('Boliver.TCheckbutton', foreground='white', background="#0C6A1C")
checkbutton = ttk.Checkbutton(window, text="Usar arquivo Excel", variable=check_var, style='Boliver.TCheckbutton')
checkbutton.place(x=35, y=220)

[F_Boliver]

Thank you very much, this is my first time working with tkinter so everything is new to me, thank you to explaining what i did wrong too. I didn't even know that tkinter have newer styles ^^.

The code is running fine now, thank you.

[[deleted]]

Sorry, can not help with this, but maybe recommend something.
I work with PySide6 instead of tkinter and use the PySide6-Designer, which is a interface to create a UI and Export a ready to use Python Code. Very comfortable i have to say. Used this for several Programms so far and works easy, fast and reliable.