Tkinter程序登录后触发SIGSEGV错误（退出码139）的解决方法

问题现象 #

• 启动login_screen()登录界面，使用账号user、密码test登录进入主界面后，点击搜索或描述按钮，程序崩溃并抛出错误：Process finished with exit code 139 (interrupted by signal 11: SIGSEGV)
• 直接启动main_screen()时，所有功能正常运行

问题根源 #

程序中同时创建了两个独立的Tk()实例（登录窗口和主界面窗口）。Tkinter基于Tcl/Tk实现，不支持多个主应用实例，销毁第一个Tk实例后再创建第二个，会导致底层资源冲突，触发段错误。

修复方案 #

调整程序结构，只保留一个Tk()主实例，登录窗口使用Toplevel()作为主窗口的子窗口：

from tkinter import *
from tkinter import messagebox
import json


def radio_used():
    global x
    x = radio_state.get()
    print(x)

# Listbox
def listbox_used(event):
    print(listbox.get(listbox.curselection()))

def show_list():
    global listbox
    listbox = Listbox(height=5)
    companies = []
    try:
        with open("data.json", "r") as data_file:
            data = json.load(data_file)
            companies = list(data.keys())
    except FileNotFoundError:
        messagebox.showinfo(title="Error", message="未找到数据文件。")
        return

    for idx, item in enumerate(companies):
        listbox.insert(idx, item)
    listbox.bind("<<ListboxSelect>>", listbox_used)
    listbox.grid(row=3, column=2)

## 保存数据
def save():
    bn = bname_entry.get().strip()
    nm = name_entry.get().strip()
    lc = location_entry.get().strip()
    ph = phone_entry.get().strip()
    eml = email_entry.get().strip()
    txt = text.get("1.0", END).strip()

    if not bn or not ph:
        messagebox.showinfo(title="Error", message="请确保未留空必填字段（企业名称、手机号）。")
        return

    new_data = {
        bn: {
            "Name": nm,
            "Email": eml,
            "Location": lc,
            "Phone Number": ph,
            "Value": x if 'x' in globals() else "",
            "Description": txt
        }
    }

    try:
        with open("data.json", "r") as data_file:
            data = json.load(data_file)
            data.update(new_data)
    except FileNotFoundError:
        data = new_data

    with open("data.json", "w") as data_file:
        json.dump(data, data_file, indent=4)

    # 清空输入框
    bname_entry.delete(0, END)
    phone_entry.delete(0, END)
    name_entry.delete(0, END)
    location_entry.delete(0, END)
    email_entry.delete(0, END)
    text.delete("1.0", END)

# 搜索数据
def find_data():
    bn = bname_entry.get().strip()
    if not bn:
        messagebox.showinfo(title="Error", message="请输入要搜索的企业名称。")
        return

    try:
        with open("data.json") as data_file:
            data = json.load(data_file)
    except FileNotFoundError:
        messagebox.showinfo(title="Error", message="未找到数据文件。")
        return

    if bn in data:
        info = data[bn]
        message = (f"姓名: {info['Name']}\n邮箱: {info['Email']}\n"
                   f"手机号: {info['Phone Number']}\n地址: {info['Location']}\n"
                   f"类型: {info['Value']}")
        messagebox.showinfo(title=bn, message=message)
    else:
        messagebox.showwarning(title="提示", message=f"未找到{bn}的相关信息。")

# 查看描述
def find_des():
    bn = bname_entry.get().strip()
    if not bn:
        messagebox.showinfo(title="Error", message="请输入要查询的企业名称。")
        return

    try:
        with open("data.json") as data_file:
            data = json.load(data_file)
    except FileNotFoundError:
        messagebox.showinfo(title="Error", message="未找到数据文件。")
        return

    if bn in data:
        txt = data[bn]["Description"]
        messagebox.showinfo(title="描述信息", message=txt if txt else "无描述内容")
    else:
        messagebox.showwarning(title="提示", message=f"未找到{bn}的描述信息。")

# 登录验证
def check_login():
    username = u_entry.get().strip()
    password = p_entry.get().strip()
    if username == "user" and password == "test":
        login_window.destroy()
        window.deiconify()  # 显示主窗口

# 登录界面
def login_screen():
    global login_window, u_entry, p_entry
    login_window = Toplevel(window)
    login_window.title("登录")
    login_window.config(padx=50, pady=50)
    login_window.grab_set()  # 锁定焦点到登录窗口

    login_canvas = Canvas(login_window, height=200, width=200)
    login_canvas.grid(row=0, column=1)

    # 标签
    u_label = Label(login_window, text="用户名:")
    u_label.grid(row=1, column=0)

    p_label = Label(login_window, text="密码:")
    p_label.grid(row=2, column=0)

    # 输入框
    u_entry = Entry(login_window, width=21)
    u_entry.grid(row=1, column=1)
    u_entry.focus()

    p_entry = Entry(login_window, width=21, show="*")
    p_entry.grid(row=2, column=1)

    # 按钮
    s_button = Button(login_window, text="登录", width=15, command=check_login)
    s_button.grid(row=3, column=1)

# 主界面
def main_screen():
    global window, bname_entry, name_entry, email_entry, location_entry, phone_entry, text, radio_state

    # 初始化主窗口配置
    window.title("数据管理器")
    window.config(padx=50, pady=50)

    canvas = Canvas(window, height=200, width=200)
    canvas.grid(row=0, column=1)

    # 标签
    bname_label = Label(window, text="企业名称:")
    bname_label.grid(row=1, column=0)

    name_label = Label(window, text="姓名:")
    name_label.grid(row=2, column=0)

    email_label = Label(window, text="邮箱:")
    email_label.grid(row=3, column=0)

    location_label = Label(window, text="地址:")
    location_label.grid(row=4, column=0)

    phone_label = Label(window, text="手机号:")
    phone_label.grid(row=5, column=0)

    # 输入框
    bname_entry = Entry(window, width=21)
    bname_entry.grid(row=1, column=1)
    bname_entry.focus()

    name_entry = Entry(window, width=21)
    name_entry.grid(row=2, column=1)

    email_entry = Entry(window, width=21)
    email_entry.grid(row=3, column=1)

    location_entry = Entry(window, width=21)
    location_entry.grid(row=4, column=1)

    phone_entry = Entry(window, width=21)
    phone_entry.grid(row=5, column=1)

    # 描述文本框
    text = Text(window, height=5, width=30)
    text.grid(row=6, column=1)
    text_label = Label(window, text="描述:")
    text_label.grid(row=6, column=0)

    # 按钮
    search_button = Button(window, text="搜索", width=13, command=find_data)
    search_button.grid(row=1, column=2)

    # 单选按钮
    radio_state = StringVar()
    radiobutton1 = Radiobutton(window, text="竞争对手", value="Competitor", variable=radio_state, command=radio_used)
    radiobutton2 = Radiobutton(window, text="客户", value="Client", variable=radio_state, command=radio_used)

    radiobutton1.grid(row=7, column=1)
    radiobutton2.grid(row=8, column=1)

    company_list_button = Button(window, text="显示企业列表", command=show_list)
    company_list_button.grid(row=2, column=2)

    add_button = Button(window, text="添加", width=36, command=save)
    add_button.grid(row=9, column=1)

    des_button = Button(window, text="查看描述", width=36, command=find_des)
    des_button.grid(row=10, column=1)

# 程序入口
if __name__ == "__main__":
    window = Tk()
    window.withdraw()  # 先隐藏主窗口
    main_screen()
    login_screen()
    window.mainloop()

额外优化点 #

• 简化登录验证逻辑，移除冗余的cypher()和user()函数
• 密码输入框添加show="*"隐藏输入内容
• 增加输入空值检查，提升用户体验
• 优化JSON读写逻辑，减少代码冗余
• 登录窗口添加grab_set()，确保用户必须完成登录才能操作主窗口

内容的提问来源于stack exchange，提问作者Adam