Question

我的以下代码要求用户导入文件，然后它将显示在标签上。一旦标签显示大的内容（即大文本文件），就会显示AutoScrollbar。我尝试过代码，但导入大文本文件时不会出现AutoScrollbar：

import tkinter 
from tkinter import * 
from tkinter.filedialog import askopenfile 
from tkinter.filedialog import askopenfilename

class AutoScrollbar(Scrollbar):
    def set(self, lo, hi):
        if float(lo) <= 0.0 and float(hi) >= 1.0:
            self.tk.call("grid", "remove", self)
        else:
            self.grid()
        Scrollbar.set(self, lo, hi)
    def pack(self, **kw):
        raise TclError ("cannot use pack with this widget")
    def place(self, **kw):
        raise TclError ("cannot use place with this widget")

def import_txt():
    global import_list
    file_name = askopenfilename(filetypes=[("Text files","*.txt")]) 
    import_list = []

    with open(file_name, 'r') as f:
        go.grid()
        import_list = f.readlines()
    f.close()

def display():
    go.grid_forget()
    start.grid_forget()
    global import_list
    new = "".join(import_list)
    canvas.create_text(100,10, anchor=NW, text=str(new))
    canvas.grid()

window = tkinter.Tk()

vscrollbar = AutoScrollbar(window)
vscrollbar.grid(row=0, column=1, sticky=N+S)
hscrollbar = AutoScrollbar(window, orient=HORIZONTAL)
hscrollbar.grid(row=1, column=0, sticky=E+W)

canvas = Canvas(window, 
                yscrollcommand=vscrollbar.set,
                xscrollcommand=hscrollbar.set)
canvas.grid(row=0, column=0, sticky=N+S+E+W)

vscrollbar.config(command=canvas.yview)
hscrollbar.config(command=canvas.xview)

window.grid_rowconfigure(0, weight=1)
window.grid_columnconfigure(0, weight=1)

frame = Frame(canvas)
frame.rowconfigure(1, weight=1)
frame.columnconfigure(1, weight=1)

canvas.create_window(0, 0, anchor=NW, window=frame)

frame.update_idletasks()

canvas.config(scrollregion=canvas.bbox("all"))

disp = tkinter.Label(window)


start = tkinter.Button(window, text="Import", command=import_txt)
start.grid()

go = tkinter.Button(window, text="GO", command=display)

window.mainloop()

我也尝试过使用：

disp.config(text=str(new))
disp.grid()

但AutoScrollbar仍然不会出现。

标签显示大文本文件时不显示AutoScrollbar

0 个答案: