how do i put dynamically added entry fields in a set frame or canvas that does not resize

Question

i have dynamically addable and delete able entry fields that i want to set inside a frame or canvas inside of a main frame but when i try the frame dissappears or dynamically grows with the entry fields. i want the canvas to use the scrollbar if entry fields exceed the window size.

from tkinter import *
import tkinter as tk
class Demo2:
    def __init__(self, master):
        global rows

    self.master = master      
    self.frame = tk.Frame(self.master)
    master.title("test")

    self.frame.pack()
    addboxButton = Button(self.frame, text='<Add Time Input>', fg="Red", command=self.addBox)
    addboxButton.pack()

this is where my buttons are added and deleted.

def addBox(self):         
    def delete():
        delboxButton.grid_remove()
        ent1.delete(0,END)
        ent2.delete(0,END)
        ent1.grid_remove()
        ent2.grid_remove()
    root = self.frame
    frame=Frame(root,width=900,height=900)
    frame.pack()
    canvas=Canvas(frame,bg='#FFFFFF',width=700,height=300,scrollregion=(0,0,700,300))
    vbar=Scrollbar(frame,orient=VERTICAL)
    vbar.pack(side=RIGHT,fill=Y)
    vbar.config(command=canvas.yview)
    canvas.config(width=700,height=300)
    canvas.config(yscrollcommand=vbar.set)
    canvas.pack(side=LEFT,expand=TRUE,fill=BOTH)

I am trying to figure out now how to make the first set of entry start out on the screen when its opened. and bind the add call to an action.

    i = 0
    ent1 = Entry(canvas)
    ent1.grid(row=i, column=0,sticky="nsew")
    i += 1
    i = 0
    ent2 = Entry(canvas)
    ent2.grid(row=i, column=1,sticky="nsew")
    i += 1        

    delboxButton = Button(canvas, text='delete', fg="Red", command=delete)
    delboxButton.grid(row=0 ,column=2)

root = tk.Tk()
root.title("test Complete")
root.geometry("500x500")
app = Demo2(root)
root.mainloop()

Answer 1

The normal way this is tackled is to create a single frame and add it to the canvas with the canvas create_window method. Then, you can put whatever you want in the frame using pack, place or grid.

For a description of the technique see Adding a scrollbar to a group of widgets in Tkinter

Here's an example illustrating how the technique works for widgets created by a button. I didn't include the delete functionality or the ability for everything to resize properly to keep the example short, but you seem to have a pretty good idea of how to make the delete function work and I don't know exactly what sort of resize behavior you want.

import tkinter as tk

class Demo2:
    def __init__(self, master):
        self.master = master
        self.entries = []

        self.canvas = tk.Canvas(master, width=400, height=200)
        self.vsb = tk.Scrollbar(master, orient="vertical", command=self.canvas.yview)
        self.canvas.configure(yscrollcommand=self.vsb.set)
        self.add_button = tk.Button(master, text="Add", command=self.add)
        self.container = tk.Frame()

        self.canvas.create_window(0, 0, anchor="nw", window=self.container)
        self.add_button.pack(side="top")
        self.vsb.pack(side="right", fill="y")
        self.canvas.pack(side="left", fill="both", expand=True)

        # start with 3 entry widgets
        self.add()
        self.add()
        self.add()

    def add(self):
        entry = tk.Entry(self.container)
        entry.pack(side="top", fill="x")
        self.canvas.configure(scrollregion=self.canvas.bbox("all"))

        self.entries.append(entry)

root = tk.Tk()
demo = Demo2(root)
root.mainloop()