Tkinter python Scrolled Window / Frame / Canvas with Mousewheel support ( based upon EugeneBakin 's scrframe.py )

ScrolledFrame.py

from tkinter import ttk
import tkinter as tk
import functools
fp = functools.partial

class VerticalScrolledFrame(ttk.Frame):
    """
    A pure Tkinter scrollable frame that actually works! 
    * Use the 'interior' attribute to place widgets inside the scrollable frame
    * Construct and pack/place/grid normally
    * This frame only allows vertical scrolling
    * -- NOTE: You will need to comment / uncomment code the differently for windows or linux 
    * -- or write your own 'os' type check.
    * This comes from a different naming of the the scrollwheel 'button', on different systems.
    """
    def __init__(self, parent, *args, **kw):

        # track changes to the canvas and frame width and sync them,
        # also updating the scrollbar
        def _configure_interior(event):
            # update the scrollbars to match the size of the inner frame
            size = (interior.winfo_reqwidth(), interior.winfo_reqheight())
            canvas.config(scrollregion="0 0 %s %s" % size)
            if interior.winfo_reqwidth() != canvas.winfo_width():
                # update the canvas's width to fit the inner frame
                canvas.config(width=interior.winfo_reqwidth())

        def _configure_canvas(event):
            if interior.winfo_reqwidth() != canvas.winfo_width():
                # update the inner frame's width to fill the canvas
                canvas.itemconfigure(interior_id, width=canvas.winfo_width())

        """
        This is linux code for scrolling the window, 
        It has different buttons for scrolling the windows
        """
        def _on_mousewheel(event, scroll):
            canvas.yview_scroll(int(scroll), "units")

        def _bind_to_mousewheel(event):
            canvas.bind_all("<Button-4>", fp(_on_mousewheel, scroll=-1))
            canvas.bind_all("<Button-5>", fp(_on_mousewheel, scroll=1))

        def _unbind_from_mousewheel(event):
            canvas.unbind_all("<Button-4>")
            canvas.unbind_all("<Button-5>")


        """
        This is windows code for scrolling the Frame

        def _on_mousewheel(event):
            canvas.yview_scroll(int(-1*(event.delta/120)), "units")

        def _bind_to_mousewheel(event):
            canvas.bind_all("<MouseWheel>", _on_mousewheel)

        def _unbind_from_mousewheel(event):
            canvas.unbind_all("<MouseWheel>")
        """

        ttk.Frame.__init__(self, parent, *args, **kw)

        # create a canvas object and a vertical scrollbar for scrolling it
        vscrollbar = ttk.Scrollbar(self, orient=tk.VERTICAL)
        vscrollbar.pack(fill=tk.Y, side=tk.RIGHT, expand=tk.FALSE)
        canvas = tk.Canvas(self, bd=0, highlightthickness=0,
                           yscrollcommand=vscrollbar.set)
        canvas.pack(side=tk.LEFT, fill=tk.BOTH, expand=tk.TRUE)
        vscrollbar.config(command=canvas.yview)

        # reset the view
        canvas.xview_moveto(0)
        canvas.yview_moveto(0)

        # create a frame inside the canvas which will be scrolled with it
        self.interior = interior = ttk.Frame(canvas)
        interior_id = canvas.create_window(0, 0, window=interior,
                                           anchor=tk.NW)

        interior.bind('<Configure>', _configure_interior)
        canvas.bind('<Configure>', _configure_canvas)
        canvas.bind('<Enter>', _bind_to_mousewheel)
        canvas.bind('<Leave>', _unbind_from_mousewheel)


# Thanks to chlutz214 for the usage update:
if __name__ == "__main__":
        # Set Up root of app
        root = tk.Tk()
        root.geometry("400x500+50+50")
        root.title("VerticalScrolledFrame Sample")

        # Create a frame to put the VerticalScrolledFrame inside
        holder_frame = tk.Frame(root)
        holder_frame.pack(side=tk.LEFT, fill=tk.BOTH, expand=tk.TRUE)

        # Create the VerticalScrolledFrame
        vs_frame = VerticalScrolledFrame(holder_frame)
        vs_frame.pack(side=tk.BOTTOM, fill=tk.BOTH, expand=tk.TRUE)

        # Fill the VerticalScrolledFrame
        i = 0
        while i != 100:
            item = tk.Entry(vs_frame.interior)
            item.insert(0, i)
            item.pack(side=tk.TOP, fill=tk.X, expand=tk.TRUE)
            i = i + 1

        # Run mainloop to start app
        root.mainloop()

I copied the code and ran on my mac, it seems only when my pointer is on the scroll bar the mousewheel would work, if it's on the frame it self it doesn't, tried multiple modifications but can't find any fix :(