使用tkinter的画布框架布局

Question

I'm added canvas and a scroll bar to one of the frames in my script. However somethings wrong cause the scroll bar is off (lower bottom is not visible) and the text I drew is off. Could anyone please tell me whats the problem ? I want the canvas to fill the whole frame (obviously without the scroll bar)

import sys
import os

if sys.version_info[0] < 3:
    import Tkinter as tk
    import ttk as ttk
else:
    import tkinter as tk
    import tkinter.ttk as ttk

#
# LeftMiddle
#
class LeftMiddle(tk.Frame):
    def __init__(self, master=None):
        self.parent = master
        tk.Frame.__init__(self, self.parent, bg='bisque', borderwidth=1, relief="sunken")
        self.__create_layout()
        self.draw_text()

    def __create_layout(self):
        self.canvas = tk.Canvas(self, bg="green", relief=tk.SUNKEN)
        self.canvas.config(width=20, height=10)
        self.canvas.config(highlightthickness=0)

        self.sbar = tk.Scrollbar(self, orient=tk.VERTICAL)

        self.sbar.pack(side=tk.RIGHT, fill=tk.Y)
        self.canvas.pack(side=tk.LEFT, expand="YES", fill=tk.BOTH)

    def draw_text(self):    
        self.canvas.create_text(0, 0, text='1234567890', fill='red')
        self.canvas.create_text(0, 25, text='ABCDEFGH', fill='blue')

#
# MainWindow
#
class MainWindow(tk.Frame):
    def __init__(self, master=None):
        self.parent = master
        tk.Frame.__init__(self, self.parent, bg='bisque', borderwidth=1, relief="sunken")
        self.__create_layout()

    def __create_layout(self):
        self.frame1 = tk.Frame(self, bg="yellow")
        self.frame2 = tk.Frame(self, bg="blue")
        self.frame3 = LeftMiddle(self)  # tk.Frame(self, bg="green")
        self.frame4 = tk.Frame(self, bg="brown")
        self.frame5 = tk.Frame(self, bg="pink")

        self.frame1.grid(row=0, column=0, rowspan=4, columnspan=8, sticky=(tk.N, tk.S, tk.W, tk.E))
        self.frame2.grid(row=0, column=8, rowspan=4, columnspan=2, sticky=(tk.N, tk.S, tk.W, tk.E))
        self.frame3.grid(row=4, column=0, rowspan=2, columnspan=5, sticky=(tk.N, tk.S, tk.W, tk.E))
        self.frame4.grid(row=4, column=5, rowspan=2, columnspan=5, sticky=(tk.N, tk.S, tk.W, tk.E))
        self.frame5.grid(row=5, column=0, rowspan=1, columnspan=10, sticky=(tk.N, tk.S, tk.W, tk.E))

        for r in range(6):
            self.rowconfigure(r, weight=1)
        for c in range(10):
            self.columnconfigure(c, weight=1)
#
#   MAIN
#
def main():
    root = tk.Tk()

    root.title("Frames")
    root.geometry("550x300+525+300")

    root.configure(background="#808080")
    root.option_add("*font", ("Courier New", 9, "normal"))

    window = MainWindow(master=root)
    window.pack(side="top", fill="both", expand=True)
    root.mainloop()

if __name__ == '__main__':
    main()

Answer 1

You have overlapping frames. Both self.frame3 and self.frame4 are in row 4 with a rowspan of 2, meaning they occupy rows 4 and 5. self.frame5 is also in row 5. So, self.frame5 is obscuring the bottom half of self.frame3 , the frame that contains the canvas.

I don't understand why you have so many rowspans, they seem completely unnecessary unless you have some specific reason why you want multiple rows and columns but only single frames that span these rows and columns. Looking at the screenshot I see the need for only three rows.

The reason the text seems off is that by default the text is centered over the coordinate you give. You might want to look at the anchor option for the create_text method.