Change OnScreen Keyboard StringVar (Show linked to one Entry)

[Diego Lelis]

Hi guys, im having a little problem to make the StringVar Linked to my OnScreen Keyboard Change when the user click in one Entry.

Here's my code:
from tkinter import *

____________________________Begin Code_______________________________________

def frame(root, side):
    w = Frame(root)
    w.pack(side=side, expand=YES, fill=BOTH)
    return w

def button(root, side, text, command=None):
    w = Button(root, text=text, command=command)
    w.pack(side=side, expand=YES, fill=BOTH)
    return w


class Keyboard(Frame):
    def __init__(self):
        Frame.__init__(self)
        self.option_add('*Font', 'Verdana 12 bold')
        self.pack(expand=YES, fill=BOTH)
        self.master.title('Simple Screen Keyboard')

        def detect_Focus(event):
            print ('Change selected_display to the display correspondent to selected entry')

        display_1 = StringVar()
        entry_1 = Entry(self, relief=SUNKEN, textvariable=display_1)
        entry_1.bind('<FocusIn>', detect_Focus)
        entry_1.pack(side=TOP, expand=YES, fill=BOTH)


        display_2 = StringVar()
        entry_2 = Entry(self, relief=SUNKEN, textvariable=display_2)
        entry_2.bind('<FocusIn>', detect_Focus)
        entry_2.pack(side=TOP, expand=YES, fill=BOTH)

        selected_display = display_1

        for key in ("123", "456", "789", "-0."):
            keyF = frame(self, TOP)
            for char in key:
                button(keyF, LEFT, char,
                       lambda w=selected_display, c=char: w.set(w.get() + c))

if __name__ == '__main__':
    Keyboard().mainloop()


____________________________End Code_______________________________________


When i run the detect_Focus Function, i wanted change the selected_display, to make the user change the entry2(display_2), using my on screen keyboard.

Thanks in advance!