自定义Tkinter窗口小部件不会在顶层打包吗？

Question

I'm trying to make a custom Tkinter widget by subclassing a Frame to make a scrollable widget that contains items. I have 2 windows, my root window and a toplevel window and I need my custom widget to pack to the toplevel window.

My problem is, that despite making 'top' the parent of my custom widget, it still packs in the root window. I've tried other widgets and they pack to the toplevel window fine.

my code:

from tkinter import *

root = Tk()
root.config(bg="#000000")
root.wm_attributes("-alpha","0.7")

top = Toplevel()
top.config(bg="#000001")
top.wm_attributes("-topmost",1)
top.wm_attributes("-transparentcolor","#000001")
top.wm_title("TOPLEVEL")



class Scrollygrid(Frame):
    def __init__(self, parent, columns, h, w):
        super(Scrollygrid, self).__init__()
        self.scrollbar = Scrollbar(self)
        self.scrollbar.pack(side = RIGHT, fill = Y)
        self.area = Canvas(self, yscrollcommand=self.scrollbar.set, width = w, height = h, bg = "#000001", bd = 0, highlightthickness = 0)
        self.gridframe = Frame(height = h*10, width = w, bg = "#FF0000")
        self.gridframe.pack_propagate(0)
        self.area.create_window((0, 0), window = self.gridframe)
        for i in range(500):
            Label(self.gridframe, text = i).pack()
        self.area.pack()
        self.area.config(scrollregion = (self.area.bbox("all")))
        self.scrollbar.config(command = self.area.yview)
        def onScroll(event):
            self.area.yview_scroll(int(-1*(event.delta/60)), "units")
        self.area.bind_all("<MouseWheel>", onScroll)
        self.scrollbar.pack_forget() #scroll wheel still works!

testgrid = Scrollygrid(top, 1,root.winfo_screenheight()-80,root.winfo_screenwidth()-(root.winfo_screenwidth()/10))
testgrid.pack(side = RIGHT, anchor = CENTER)

root.mainloop()

the transparent color and alpha level have been left in to make it more immediately obvious which window is which.

Answer 1

top isn't the parent of your custom widget. You're never passing it. Your Scrollygrid is being passed a parent parameter and that's it . Nothing tells it to assign it as the parent as an attribute even. So the parent defaults to the Tk instance, root .

Replace:

super(Scrollygrid, self).__init__()

with:

super(Scrollygrid, self).__init__(parent)

In order to pass the given widget argument as the parent to the superclass, Frame . Essentially making the Toplevel , top your custom class' parent. Upon which you'll get further error(s) but the parent is correctly assigned. Verify by:

print(repr(self.winfo_toplevel()))