why is a button unclickable in tkinter python

Question

In this code there are two problems.

1. The buttons created in create_folder are unclickable.
2. the image is not being inserted in the buttons.
   Thanks in advance for any help.

---

import tkinter as tk
from os import listdir
from PIL import ImageTk,Image


def __init__(self, parent):
    tk.Frame.__init__(self, parent)
    self.canvas = tk.Canvas(self)
    self.canvas.pack(side="left", fill="both", expand=1)
    self.scrollbar = tk.Scrollbar(self, orient="vertical", command=self.canvas.yview)
    self.scrollbar.pack(side="right", fill="y")
    self.canvas.configure(yscrollcommand=self.scrollbar.set)
    self.canvas.bind("<Configure>", lambda event: self.canvas.configure(scrollregion=self.canvas.bbox("all")))
    self.frame = tk.Frame(self.canvas)
    self.canvas.create_window((0, 0), window=self.frame, anchor="nw")
    self.path = "D:"
    self.val = 0

def create_folder(self):
    lst = list(f for f in listdir("D:") if f[0] != "$")
    p1 = ImageTk.PhotoImage(file="Folder.png")
    for ech in lst:
        button = tk.Button(master=self.frame, image=p1, text=ech, width=750, height=13, compound="left", anchor="w",
                           borderwidth=0.5)
        button.pack(anchor="w")

if __name__ == "__main__":
    root = tk.Tk()
    root.geometry("600x600")
    ex = explorer(root)
    ex.create_folder(ex.path)
    ex.pack(side="top", fill="both", expand=1)
    root.mainloop()