【发布时间】：2015-10-18 01:03:54
【问题描述】：
我正在尝试编写一个利用 Tkinter 窗口切换 OOP 类的 python 程序。在起始页面上，有一个输入表单，用户可以在其中填写相关字段。填写表格后点击“to tests”按钮，用户可以在切换框架/窗口后选择测试，输入的用户信息同时保存为.txt文件，因为这个按钮运行了几个Startpage 类中的方法。通过单击测试 1 页面中的是或否按钮接收数据时会出现问题。
此页面在不同的类中运行，但需要 Startpage 类中定义的方法 get_info() 的返回值，以获取输入的用户信息（文件名），以创建第二个 .txt 文件以存储原始数据，存储附加的 ' yes' 或 'no' 字符串取决于在测试 1 的 GUI 窗口中单击的按钮。
但是，由于 Test1 没有从 Startpage 类/窗口接收任何条目数据，因此从未创建此文件，因此无法为第二个 .txt 文件分配文件名（调用包含 widget.get() 函数的 get_info() ）。
通过类中的方法正确获取信息，一切正常。然而，当 Test1 要求从 Startpage 接收 widget.get() 变量/方法时，问题就出现了。
抛出的错误如下IndexError：
Exception in Tkinter callback
Traceback (most recent call last):
File "C:\Users\Rylan\Anaconda\lib\lib-tk\Tkinter.py", line 1532, in __call__
return self.func(*args)
File "C:/Users/Rylan/Documents/Python/Basel Summerintern files/code to help with question.py", line 280, in update_countyes
directory = "C:\Users\Rylan\Documents\Python\Basel Summerintern files\{}".format(self.get_t_info())
File "C:/Users/Rylan/Documents/Python/Basel Summerintern files/code to help with question.py", line 304, in get_t_info
self.gettheinfo = Startpage(app, self.controller).get_info()
File "C:/Users/Rylan/Documents/Python/Basel Summerintern files/code to help with question.py", line 170, in get_info
str(Day) + "_" + str(Month) + "_" +
IndexError: string index out of range
我对 OOP 编程非常陌生，据我所知，这可能是由以下原因引起的：
- 未正确引用/调用 Startpage 实例，因此 Test1 未接收到变量，因此调用 get_info() 方法会导致 get_info() 方法中的嵌套 widget.get() 函数/变量没有收到任何内容.
基本上，这个 IndexError 的原因是什么？如何修复它以获取从 Startpage 类中的 get_info() 方法创建/返回的文件名，该方法发送到/由类 Test1 调用？
我已经看到与从不同类调用类变量和方法有关的类似问题，但是没有一个考虑窗口/框架切换 Tkinter 应用程序的情况。
下面是可以运行的简化代码（可能看起来不像）（您可能存在目录路径存在问题，只需将路径更改为可以轻松找到的任何内容以保存 .txt 文件）
import Tkinter as tk
import ttk
import os
LARGE_FONT = ("Verdana", 12)
NORM_FONT = ("Verdana", 10)
SMALL_FONT = ("Verdana", 8)
def center(win):
"""
centers a tkinter window
param win: the window to center on the screen
"""
win.update_idletasks()
width = win.winfo_width()
frm_width = win.winfo_rootx() - win.winfo_x()
win_width = width + 2 * frm_width
height = win.winfo_height()
titlebar_height = win.winfo_rooty() - win.winfo_y()
win_height = height + titlebar_height + frm_width
x = win.winfo_screenwidth() // 2 - win_width // 2
y = win.winfo_screenheight() // 2 - win_height // 2
win.geometry('{}x{}+{}+{}'.format(width, height, x, y))
win.deiconify()
def popupmsg(msg):
popup1 = tk.Tk()
center(popup1)
popup1.minsize(width=60, height=70)
popup1.maxsize(width=60, height=70)
popup1.wm_title("Attention!")
label = ttk.Label(popup1, text=msg, font=NORM_FONT, anchor="center")
label.pack(side="top", fill="x", pady=10)
b1 = ttk.Button(popup1, text="Ok", command=lambda: popup1.destroy())
b1.pack()
popup1.mainloop()
class Testapp(tk.Tk):
def __init__(self, *args, **kwargs):
tk.Tk.__init__(self, *args, **kwargs)
tk.Tk.iconbitmap(self, default="testappicon2.ico")
tk.Tk.wm_title(self, "Psychoacoustic Tests")
container = ttk.Frame(self)
container.pack(side="top", fill="both", expand=True)
container.grid_columnconfigure(0, weight=1)
container.grid_rowconfigure(0, weight=1)
menubar = tk.Menu(container)
filemenu = tk.Menu(menubar, tearoff=0)
filemenu.add_separator()
filemenu.add_command(label="Exit", command=lambda: self.destroy())
menubar.add_cascade(label="File", menu=filemenu)
tk.Tk.config(self, menu=menubar)
self.frames = {}
for F in (Startpage, TestSelect, Test1):
frame = F(container, self)
self.frames[F] = frame
self.minsize(width=900, height=500)
frame.grid(row=0, column=0, sticky="nsew")
self.show_frame(Startpage)
def show_frame(self, cont):
frame = self.frames[cont]
frame.tkraise()
class Startpage(ttk.Frame):
def __init__(self, parent, controller):
ttk.Frame.__init__(self, parent)
self.controller = controller
self.titlelabel = ttk.Label(self, text="User Information", font = LARGE_FONT)
self.titlelabel.grid(row=0, column=0, columnspan=4, padx = 10, pady = 10)
self.firstnamelabel = ttk.Label(self, text="First Name: ", font = NORM_FONT)
self.firstnamelabel.grid(row=1, column=0, sticky = 'w', padx = 15, pady = 10)
self.lastnamelabel = ttk.Label(self, text="Last Name: ", font = NORM_FONT)
self.lastnamelabel.grid(row=2, column=0, sticky = 'w', padx = 15, pady = 10)
self.firstnameentry = ttk.Entry(self)
self.firstnameentry.grid(row=1, column=1, padx=5, sticky = 'we', columnspan = 3)
self.lastnameentry = ttk.Entry(self)
self.lastnameentry.grid(row=2, column=1, padx=5, sticky = 'we', columnspan = 3)
self.birthdaylabel = ttk.Label(self, text="Birthday: ", font = NORM_FONT)
self.birthdaylabel.grid(row=3, column=0, sticky = 'w', padx = 15, pady = 10)
self.daydropdown = ttk.Combobox(self, justify='center', height=20, width=2,
values = (1,2,3,4,5,6,7,8,9,10,11,12,13,14,
15,16,17,18,19,20,21,22,23,24,25,
26,27,28,29,30,31),
state='readonly')
self.daydropdown.grid(row=3, column=1, padx = 3, sticky = 'ew')
self.monthdropdown = ttk.Combobox(self, justify='center', height=12, width=10,
values = ('January','Feburary','March',
'April','May','June','July',
'August','September','October',
'November','December'),
state='readonly')
self.monthdropdown.grid(row=3, column=2, padx=3, sticky = 'ew')
self.yeardropdown = ttk.Combobox(self, justify='center', height=20, width=4,
values = (1980, 1981, 1982, 1983, 1984,
1985, 1986, 1987, 1988, 1989,
1990, 1991, 1992, 1993, 1994,
1995, 1996, 1997, 1998, 1999),
state = 'readonly')
self.yeardropdown.grid(row=3, column=3, padx = 3, sticky = 'ew')
self.genderlabel = ttk.Label(self, text="Gender: ", font = NORM_FONT)
self.genderlabel.grid(row=4, column=0, sticky = 'w', padx = 15, pady = 10)
self.var = tk.IntVar()
self.Maleradio = ttk.Radiobutton(self, text='Male', variable=self.var, value = 1)
self.Maleradio.grid(row=4, column=1, sticky = 'w')
self.Femaleradio = ttk.Radiobutton(self, text='Female', variable=self.var, value = 2)
self.Femaleradio.grid(row=5, column=1, sticky = 'w')
self.emaillabel = ttk.Label(self, text="Email: ", font = NORM_FONT)
self.emaillabel.grid(row=6, column=0, sticky = 'w', padx = 15, pady = 10)
self.emailentry = ttk.Entry(self)
self.emailentry.grid(row=6, column=1, columnspan=3, sticky='ew')
self.experiencelabel = ttk.Label(self, text="Musical Experience: ", font = NORM_FONT)
self.experiencelabel.grid(row=7, column=0, sticky = 'w', padx = 15, pady = 10)
self.expdropdown = ttk.Combobox(self, justify='center', height=3, width=17,
values = ('No experience', 'Some experience',
'Musician level'), state='readonly')
self.expdropdown.grid(row=7, column=1, columnspan=3, sticky = 'w')
self.button1 = ttk.Button(self, text="To Tests", command= lambda: self.checkempty())
self.button1.grid(row=8, column=3)
def shortcut():
controller.show_frame(TestSelect)
buttonshort = ttk.Button(self, text="To Tests shortcut", command= lambda: shortcut())
buttonshort.grid(row=9, column=3)
def get_info(self):
Name = self.firstnameentry.get()
Surname = self.lastnameentry.get()
Day = self.daydropdown.get()
Month = self.monthdropdown.get()
Year = self.yeardropdown.get()
foldername = (str(Name[0]) + str(Surname[0]) +
str(Day) + "_" + str(Month) + "_" +
str(Year))
return foldername
def create_directory(self):
if not os.path.isdir(self.get_info()):
directory = "C:\Users\Rylan\Documents\Python\Basel Summerintern files\{}".format(self.get_info())
os.makedirs(directory)
datafile = "{}_userinfo.txt".format(self.get_info())
entirefile = os.path.join(directory, datafile)
myfile = open(entirefile, 'w')
myfile.write(self.userinfo())
myfile.close()
self.controller.show_frame(TestSelect)
else:
popupmsg("Folder already exists")
def userinfo(self):
Name = self.firstnameentry.get()
Surname = self.lastnameentry.get()
Day = self.daydropdown.get()
Month = self.monthdropdown.get()
Year = self.yeardropdown.get()
Email = self.emailentry.get()
Experience = self.expdropdown.get()
def genderget():
Gender = self.var.get()
if Gender == 1:
UserGender = "Male"
elif Gender == 2:
UserGender = "Female"
return UserGender
user_info = ("Participant Name: " + str(Name) + " " +
str(Surname) + "\nBirthday: " + str(Day) + "_" +
str(Month) + "_" + str(Year) + "\nGender: " +
str(genderget()) + "\nEmail: " + str(Email) +
"\nMusical Experience: " + str(Experience) +
"\nDirectory Name: " + str(self.get_info()))
return user_info
def checkempty(self):
Name = self.firstnameentry.get()
Surname = self.lastnameentry.get()
Day = self.daydropdown.get()
Month = self.monthdropdown.get()
Year = self.yeardropdown.get()
Email = self.emailentry.get()
Experience = self.expdropdown.get()
if len(Name) == 0:
popupmsg("Please complete the user information form")
elif len(Surname) == 0:
popupmsg("Please complete the user information form")
elif Day == None:
popupmsg("Please complete the user information form")
elif Month == None:
popupmsg("Please complete the user information form")
elif Year == None:
popupmsg("Please complete the user information form")
elif self.var.get() == 0:
popupmsg("Please complete the user information form")
elif len(Email) == 0:
popupmsg("Please complete the user information form")
elif Experience == None:
popupmsg("Please complete the user information form")
else:
self.create_directory()
class TestSelect(ttk.Frame):
def __init__(self, parent, controller):
ttk.Frame.__init__(self, parent)
self.controller = controller
label = ttk.Label(self, text="Select tests", font = LARGE_FONT)
label.grid(row=0, column=0, columnspan=3)
Test1Button = ttk.Button(self, text="Do test 1", command=lambda: controller.show_frame(Test1))
Test1Button.grid(row=1, column=0, padx = 20, pady = 15, sticky = 'nsew')
button2 = ttk.Button(self, text="Home", command=lambda: controller.show_frame(Startpage))
button2.grid(row=3, column=2)
class Test1(ttk.Frame):
def __init__(self, parent, controller):
ttk.Frame.__init__(self, parent)
self.controller = controller
label = ttk.Label(self, text="Test 1", font = LARGE_FONT)
label.grid(row=0, column=0, columnspan=2)
button2 = ttk.Button(self, text="Page one", command=lambda: controller.show_frame(TestSelect))
button2.grid(row=1, column=0, sticky = "w")
yesbutt1 = ttk.Button(self)
yesbutt1.grid(row=2, column=0)
nobutt1 = ttk.Button(self)
nobutt1.grid(row=2, column=1)
yesbutt1['text'] = "Yes: 0"
nobutt1['text'] = "No: 0"
self.nobttn_clicks = 0
self.yesbttn_clicks = 0
def update_countyes():
if self.yesbttn_clicks >= 1 or self.nobttn_clicks >= 1:
popupmsg("Only one answer allowed!")
else:
self.yesbttn_clicks += 1
yesbutt1['text'] = "Yes: " + str(self.yesbttn_clicks)
directory = "C:\Users\Rylan\Documents\Python\Basel Summerintern files\{}".format(self.get_t_info())
datafile = "{}_test1data.txt".format(self.get_t_info())
entirefile = os.path.join(directory, datafile)
myfile = open(entirefile, 'a')
myfile.write('\nyes')
myfile.close()
def update_countno():
if self.yesbttn_clicks >= 1 or self.nobttn_clicks >= 1:
popupmsg("Only one answer allowed!")
else:
self.nobttn_clicks += 1
nobutt1['text'] = "No: " + str(self.nobttn_clicks)
directory = "C:\Users\Rylan\Documents\Python\Basel Summerintern files\{}".format(self.get_t_info())
datafile = "{}_test1data.txt".format(self.get_t_info())
entirefile = os.path.join(directory, datafile)
myfile = open(entirefile, 'a')
myfile.write('\nno')
myfile.close()
yesbutt1['command'] = update_countyes
nobutt1['command'] = update_countno
def get_t_info(self):
self.gettheinfo = Startpage(app, self.controller).get_info()
return self.gettheinfo
app = Testapp()
app.mainloop()
【问题讨论】：
标签： python class user-interface oop tkinter