调整画布的大小，使其与tkinter python中的帧大小相等

Question

我有两个问题与此附加代码有关。此代码是我的项目的一部分，我必须管理50名（或更多）学生的出勤率

1. 当您运行这段代码时，您将看到标签框（即考勤框）内有一个额外的空白（可能是画布）。我所想要的是，不应该有额外的空白，滚动条，而不是在最右边，应该在标签结束的地方。 我已经找到了我问题的答案，并看到了一个类似的案例。但在那里，人们希望框架扩展到画布大小。链接（Tkinter: How to get frame in canvas window to expand to the size of the canvas?）。 但在我的例子中，我希望画布的大小等于框架的大小（尽管框架位于画布内部）

2. 我想要的另一件事是，所有复选框最初都应该被选中（显示当前状态），当我取消选中随机复选框（标记缺席），并单击“提交”按钮（尚未在窗口底部创建）时，我应该得到一个列表，第一个元素是“输入日期”，其他元素是卷号，即2018-MC-XX。例如：['01/08/2020'，'2018-MC-7'，'2018-MC-11'，'2018-MC-23'，'2018-MC-44']。 实际上，我的计划是当我得到一个列表时，我会很容易地将它写入一个文本文件

    from tkinter import *
    from tkcalendar import DateEntry
   
    root = Tk()
    root.geometry('920x600+270+50')
    root.minsize(920,600)
   
    Attendance_frame = Frame(root)    ### Consider it a Main Frame
    Attendance_frame.pack()
   
    attendaceBox = LabelFrame(Attendance_frame, text = 'Take Attendance', bd = 4, relief = GROOVE, labelanchor = 'n',font = 'Arial 10 bold', fg = 'navy blue', width = 850, height = 525)     # A Label Frame inside the main frame
   
    attendaceBox.pack_propagate(0)
    attendaceBox.pack(pady = 15)
   
    dateFrame = Frame(attendaceBox)    # A small frame to accommodate date entry label & entry box
    dateFrame.pack(anchor = 'w')
   
    font = 'TkDefaultFont 10 bold'
    date_label = Label(dateFrame, text = 'Enter Date : ', font = font).grid(row = 0, column =  0, sticky = 'w', padx = 10, pady = 10)
   
    date_entry = DateEntry(dateFrame, date_pattern = 'dd/mm/yyyy', showweeknumbers = FALSE, showothermonthdays = FALSE)
    date_entry.grid(row = 0, column = 1, sticky = 'w')
   
    noteLabel = Label(attendaceBox, text = 'Note: Uncheck the boxes for absentees').pack(anchor = 'w', padx = 10, pady = 5)
   
    canvas = Canvas(attendaceBox, borderwidth=0, background="#ffffff")
    checkFrame = Frame(canvas, width = 100, height = 50)
    vsb = Scrollbar(canvas, orient="vertical", command=canvas.yview)
    canvas.configure(yscrollcommand=vsb.set)
   
    vsb.pack(side="right", fill="y")
    canvas.pack(side="left", fill="both", expand=True)
    canvas.pack_propagate(0)
    canvas.create_window((4,4), window=checkFrame, anchor="nw")
   
    def onFrameConfigure(canvas):
        '''Reset the scroll region to encompass the inner frame'''
        canvas.configure(scrollregion=canvas.bbox("all"))
   
    checkFrame.bind("<Configure>", lambda event, canvas=canvas: onFrameConfigure(canvas))
   
    for i in range(0,51):     # A loop to create Labels of students roll numbers & names
        c = Checkbutton(checkFrame, text = f"{'2018-MC-'+str(i+1)}       Student {i+1}")
        c.grid(row = i, column = 0, padx = 10, sticky = 'w')
   
   
    mainloop()
   

Answer 1

所有问题的答案如下：

你应该试试这个

---

import tkinter as tk
from tkcalendar import DateEntry

root = tk.Tk()
root.geometry('920x600+270+50')
root.minsize(960, 600)

root.columnconfigure(0, weight=1)
root.rowconfigure(0, weight=1)
Attendance_frame = tk.Frame(root)
Attendance_frame.grid(row=0, column=0, sticky='nsew')

attendaceBox = tk.LabelFrame(Attendance_frame,
                             text='Take Attendance',
                             bd=4,
                             relief='groove',
                             labelanchor='n',
                             font='Arial 10 bold',
                             fg='navy blue',
                             width=850,
                             height=525)
attendaceBox.grid(row=0, column=0, sticky='nsew', padx=15)

Attendance_frame.columnconfigure(0, weight=1)
Attendance_frame.rowconfigure(0,weight=1)

dateFrame = tk.Frame(attendaceBox)  # A small frame to accommodate date entry label & entry box
dateFrame.grid(row=0, column=0, sticky='nsew')

font = 'TkDefaultFont 10 bold'
date_label = tk.Label(dateFrame, text='Enter Date : ', font=font)
date_label.grid(row=0, column=0, sticky='w', padx=10, pady=10)

date_entry = DateEntry(dateFrame, date_pattern='dd/mm/yyyy', showweeknumbers=False, showothermonthdays=False)
date_entry.grid(row=0, column=1, sticky='w')

noteLabel = tk.Label(attendaceBox, text='Note: Uncheck the boxes for absentees', anchor='w')
noteLabel.grid(row=1, column=0, sticky='nsew')

attendaceBox.rowconfigure(2, weight=1)
canvas = tk.Canvas(attendaceBox, width=200, borderwidth=0, background="#ffffff")
# You can set width of canvas according to your need
canvas.grid(row=2, column=0, sticky='nsew')
canvas.columnconfigure(0, weight=1)
canvas.rowconfigure(0, weight=1)
vsb = tk.Scrollbar(attendaceBox, orient="vertical", command=canvas.yview)
vsb.grid(row=2, column=1, sticky='nsew')
canvas.configure(yscrollcommand=vsb.set)

checkFrame = tk.Frame(canvas, bg='green')
canvas.create_window((0, 0), window=checkFrame, anchor="nw", tags='expand')
checkFrame.columnconfigure(0, weight=1)



for i in range(0, 51):  # A loop to create Labels of students roll numbers & names
    c = tk.Checkbutton(checkFrame, anchor='w', text=f"{'2018-MC-' + str(i + 1)}       Student {i + 1}")
    c.grid(row=i, column=0, sticky='nsew')
    c.select()
canvas.bind('<Configure>', lambda event: canvas.itemconfigure('expand', width=event.width))
checkFrame.update_idletasks()
canvas.config(scrollregion=canvas.bbox('all'))


root.mainloop()

---

获取选定值

vars = []
for i in range(0, 51):  # A loop to create Labels of students roll numbers & names
    var = tk.IntVar()
    c = tk.Checkbutton(checkFrame,
                       variable=var,
                       anchor='w', text=f"{'2018-MC-' + str(i + 1)}       Student {i + 1}")
    c.grid(row=i, column=0, sticky='nsew')
    c.select()
    vars.append(var)


def state():
    print(list(map((lambda var: var.get()), vars)))

Answer 2

如果要创建项目的垂直列表，则不需要在画布中使用框架。内部框架增加了一些不必要的复杂性。相反，使用create_window直接在画布上创建复选按钮

您还需要配置scrollregion属性，以便滚动条知道要滚动多少虚拟画布

最后，要选择它们，您应该为每个checkbutton分配一个变量，并确保该值是正确的值。默认情况下，复选按钮使用值0和1，因此将变量设置为1将使其处于选中状态

vars = []
for i in range(0,51):
    var = IntVar(value=1)
    vars.append(var)
    x0, y0, x1, y1 = canvas.bbox("all") or (0,0,0,0)
    c = Checkbutton(canvas, text = f"{'2018-MC-'+str(i+1)}       Student {i+1}", variable=var)
    canvas.create_window(2, y1+4, anchor="nw", window=c)
canvas.configure(scrollregion=canvas.bbox("all"))