[Tkinter] tkinter listbox problem

[edoardo5782]

Hi
i have a problem with the Listbox on Tkinter.
When i select with mouse one word in the Listbox, the program give me the relative code.
If i select another word again in the Listbox the program put the new code under the first one.
I would like that at the second selection the code before disappear.

What can I have to change?

THANK U!

(sorry for my english )

This is my code:

from tkinter import *
from tkinter.font import Font

root = Tk()
text = Text(root)

myFont = Font(family="Times New Roman", size=12)
text.configure(font=myFont)



class articoli: 

    def __init__(self,codice,modello,pezzi_ora,cod_materiale,mis_materiale,
                 ultima_mod,materiale_casa):

        self.codice = codice
        self.modello = modello
        self.pezzi_ora = pezzi_ora
        self.cod_materiale = cod_materiale
        self.mis_materiale = mis_materiale
        self.ultima_mod = ultima_mod
        self.materiale_casa = materiale_casa

        

        self.label_8 = Label() 
        self.label_8.configure(text=self.codice,font=myFont)
        self.label_8.pack(side=TOP)

        self.label_9 = Label() 
        self.label_9.configure(text=self.modello,font=myFont)
        self.label_9.pack(side=TOP)

        self.label_10 = Label() 
        self.label_10.configure(text=self.pezzi_ora,font=myFont)
        self.label_10.pack(side=TOP)

        self.label_11 = Label() 
        self.label_11.configure(text=self.cod_materiale,font=myFont)
        self.label_11.pack(side=TOP)

        self.label_12 = Label() 
        self.label_12.configure(text=self.mis_materiale,font=myFont)
        self.label_12.pack(side=TOP)

        self.label_13 = Label() 
        self.label_13.configure(text=self.ultima_mod,font=myFont)
        self.label_13.pack(side=TOP)

        self.label_14 = Label() 
        self.label_14.configure(text=self.materiale_casa,font=myFont)
        self.label_14.pack(side=TOP)


def callback(event):
    value=str((Lb1.get(ACTIVE)))
    print (value)
    sys.stdout.flush()
    
    if value== "Python":
        Ps_48 = articoli("Ps 48","Patt_inf_est","1500","NG00002","135_5","20_04_2018",
                 "20")
    elif value== "Perl":
        Ps_40 = articoli("Ps_40","patt_sup_est","1000","NG00001",
                                 "130_4","18_05_2018","2000") 
    elif value== "C":
        Ps_42 = articoli("Ps_40","patt_sup_est","1000","NG00001",
                                 "135_4","18_05_2018","3000")
    elif value== "PHP":
        Ps_45 = articoli("Ps_40","patt_sup_est","1000","NG00001",
                                 "139_4","18_05_2018","4000")
    elif value== "JSP":  
        Ps_47 = articoli("Ps_40","patt_sup_est","1000","NG00001",
                                 "140_4","18_05_2018","5000")    
      

#listbox definition
Lb1 = Listbox(selectmode=SINGLE)
Lb1.insert(1, "Python")
Lb1.insert(2, "Perl")
Lb1.insert(3, "C")
Lb1.insert(4, "PHP")
Lb1.insert(5, "JSP")

Lb1.pack(side=LEFT,fill=BOTH,expand=YES)
#scrollbar configuration       
scrollbar = Scrollbar()
scrollbar.pack(side=LEFT, fill=Y)
#listbox configuration   
Lb1.config(yscrollcommand=scrollbar.set)
scrollbar.config(command=Lb1.yview)
#double click for listbox
Lb1.bind('<Double-Button-1>',callback)

root.mainloop()