from Tkinter import *

global listbox

# A list of all the items that will be in the listbox
itemlist = ["one", "two", "three", "four"]

# This is called when the user double-clicks an item
def buttonPushedEvent(event):
    buttonPushed()

# This is called when the user clicks the button
def buttonPushed():
    items = listbox.curselection()
    items = map(int, items)
    print items
    print "The item selected was ", itemlist[items[0]]

# Add a listbox to the root window
def addListBox(root):
    global listbox

    listbox = Listbox(root) # Create the box
    
    for item in itemlist: # Add all the items from global itemlist
        listbox.insert(END, item)

    listbox.pack() # Pack it
    listbox.bind("<Double-Button-1>", buttonPushedEvent) # Allow user to doubleclick


# Add a button to the window also
def addButton(root):
    myBtn = Button(root, text="Print Selection", command=buttonPushed)
    myBtn.pack()
    
def main():
    root = Tk()
    addListBox(root)
    addButton(root)
    root.mainloop()

main()