阻止 tkinter 框架被推离屏幕

Question

我有一个 tk window 有 3 个框架，左侧像树结构一样工作，带有标签，将使用 .grid() 和 [=13= 添加和删除标签]，右侧框架将显示有关这些项目的信息，底部框架将容纳按钮。如果我在左框架 (lframe) 上展开太多项目，它会将底部框架 (bframe) 推到视野之外。我宁愿底部框架在到达 window 的边缘时停止，并且 lframe 的滚动条用于查看 lframe 的项目。

这是我看到的一个简单示例。当您单击该按钮时，将创建更多标签小部件并将 bframe 推出视图。

from tkinter import *

main = Tk()

canvas = Canvas(main)
canvas.grid(row=0, column=0)
canvas.configure(scrollregion=canvas.bbox("all"))
lframe = Frame(canvas)
lframe.grid(row=0, column=1)


sbar = Scrollbar(canvas)
sbar.config(command=canvas.yview)
canvas.config(yscrollcommand=sbar.set)
sbar.grid(row=0, column=0, sticky=NSEW)

rframe = Frame(main)
rframe.grid(row=0, column=1, sticky=N)

bframe = Frame(main)
bframe.grid(row=1, column=1)


cnt = 1
def addmore():
    global cnt

    test = Label(lframe, text='this \nis \nthe \nLEFT \nframe\nthis \nis \nthe \nLEFT \nframe\nthis \nis \nthe \nLEFT \nframe\nthis \nis \nthe \nLEFT \nframe\nthis \nis \nthe \nLEFT \nframe\n')
    test.grid(row=cnt, column=0)
    cnt += 1
    lframe.update()


llbl = Label(lframe, text='this \nis \nthe \nLEFT \nframe')
llbl.grid()

rlbl = Label(rframe, text='this is the RIGHT frame')
rlbl.grid()
btn = Button(rframe, text='click me', command=addmore)
btn.grid(row=1, column=0, sticky=N)
blbl = Label(bframe, text='this is the BOTTOM frame', bg="yellow")
blbl.grid(row=0)


main.mainloop()

问题一：如何阻止 bframe 推出屏幕？我希望它在到达 main 的底部时停止并且 lframe 中的标签开始从 bframe 后面的视图中推出。然后用户将使用滚动条查看 lframe.

中的其他项目

问题二：在让 lframe 停止推出屏幕之前，我不知道我的滚动条是否配置正确。如果设置不正确，我需要更改什么？

Answer 1

这里是一个示例，说明如何在主框架中使用权重设置此滚动 canvas。它并不完美，但应该足以提供帮助。

import tkinter as tk

class Example(tk.Frame):
    def __init__(self):

        tk.Frame.__init__(self)

        self.canvas = tk.Canvas(self, borderwidth=0, width = 50, height = 100)
        self.lframe = tk.Frame(self.canvas, width=10)
        self.sbar = tk.Scrollbar(self, orient="vertical", command=self.canvas.yview)
        self.canvas.configure(yscrollcommand=self.sbar.set)

        self.sbar.grid(row=0, column=0, rowspan=2, sticky="nsw")
        self.canvas.grid(row=0, column=1, rowspan=2, sticky="nsew")
        self.canvas.create_window((2,2), window=self.lframe, anchor="ne", 
                                  tags="self.lframe")

        self.lframe.bind("<Configure>", self.onFrameConfigure)
        self.rframe = tk.Frame(self)
        self.rframe.grid(row=0, column=2, sticky="n")

        self.bframe = tk.Frame(self)
        self.bframe.grid(row=1, column=2)

        llbl = tk.Label(self.lframe, text='this \nis \nthe \nLEFT \nframe')
        llbl.grid(row = 0, column = 0)

        rlbl = tk.Label(self.rframe, text='this is the RIGHT frame')
        rlbl.grid(row = 0, column = 0)
        btn = tk.Button(self.rframe, text='click me', command=self.addmore)
        btn.grid(row=1, column=0, sticky="n")
        blbl = tk.Label(self.bframe, text='this is the BOTTOM frame', bg="yellow")
        blbl.grid(row = 2, column = 0, sticky = "s")

        self.bframe.rowconfigure(1, weight = 1)
        self.bframe.rowconfigure(2, weight = 0)
        self.rowconfigure(0, weight = 1)
        self.rowconfigure(1, weight = 1)
        self.columnconfigure(0, weight = 0)
        self.columnconfigure(1, weight = 1)
        self.columnconfigure(2, weight = 0)

        self.cnt = 1

    def addmore(self):
        test = tk.Label(self.lframe, text='this \nis \nthe \nLEFT \nframe\nthis \nis \nthe \nLEFT \nframe\nthis \nis \nthe \nLEFT \nframe\nthis \nis \nthe \nLEFT \nframe\nthis \nis \nthe \nLEFT \nframe\n')
        test.grid(row=self.cnt, column=0)
        self.cnt += 1

    def onFrameConfigure(self, event):
        '''Reset the scroll region to encompass the inner frame'''
        self.canvas.configure(scrollregion=self.canvas.bbox("all"))

if __name__ == "__main__":
    root=tk.Tk()
    Example().grid(row=0, column=0)
    root.mainloop()

阻止 tkinter 框架被推离屏幕

Stop tkinter frame from being pushed off screen

python

tkinter

scrollbar

frame

python-3.x