Problems in Python getting multiple selections from Tkinter listbox

Question

This is the same problem I posed earlier today and which a couple of you tried to help me with, but I can't get it to work. All I want to do is to populate "ichose" with the multiple selections I make when I click on the listbox.

import Tkinter as tk
from Tkinter import *
global ichose

class App(tk.Frame):
    def __init__(self, master):
        tk.Frame.__init__(self,master)
        self.master=master
        self.grid()
        self.ichose = ()

        self.l = Listbox(self, height=10, selectmode=EXTENDED)
        # Selectmode can be SINGLE, BROWSE, MULTIPLE or EXTENDED. Default BROWSE
        self.l.grid(column=0, row=0, sticky=(N,W,E,S))
        self.l.bind("Double-Button-1", self.entered)

        s = Scrollbar(self, orient=VERTICAL, command=self.l.yview)
        s.grid(column=0, row=0, sticky=(N,S,E))
        self.l['yscrollcommand'] = s.set

        for i in range(1,101):
            self.l.insert('end', 'Line %d of 100' % i)


    def entered(self, event):
        self.ichose = self.selection_get()
        self.ichose = ('hello')

root=tk.Tk()
root.title('Listbox Problem')
root.geometry('200x200')
app=App(root)
root.mainloop()

print app.ichose

Whatever I do, "ichose" comes out as an empty tuple (). It's clear that the function "entered" is never called because I never see the test string 'hello'.

I also don't know what the various options are as in "Double-Button-", "<>" etc. Where can I find a list and explanation of each one?

If somebody could please just modify my program so the "print ichose" works, I'd be really grateful. You can see from my program that I don't really know what I'm doing but am keen to learn. Thank you.

score 2 · Answer 1 · answered Dec 13 '12 at 14:55

I've finally found the answer to my own question. This is REALLY useful if you want to capture multiple responses from a listbox. I've commented a lot. Hope it helps!

import Tkinter as tk
from Tkinter import *

class App(tk.Frame):
    def __init__(self, master):
        tk.Frame.__init__(self,master)
        self.master=master
        self.grid()
        self.ichose = []

        self.l = Listbox(self, height=10, selectmode=MULTIPLE)
        # Selectmode can be SINGLE, BROWSE, MULTIPLE or EXTENDED. Default BROWSE
        self.l.grid(column=0, row=0, sticky=(N,W,E,S))

        s = Scrollbar(self, orient=VERTICAL, command=self.l.yview)
        s.grid(column=0, row=0, sticky=(N,S,E))
        self.l['yscrollcommand'] = s.set

        for i in range(1,101):
            self.l.insert('end', 'Line %d of 100' % i)

        # Create Textbox that will display selected items from list
        self.selected_list = Text(self,width=20,height=10,wrap=WORD)
        self.selected_list.grid(row=12, column=0, sticky=W)        

        # Now execute the poll() function to capture selected list items
        self.ichose = self.poll()

    def poll(self):
        items =[]
        self.ichose = []
        # Set up an automatically recurring event that repeats after 200 millisecs
        self.selected_list.after(200, self.poll)
        # curselection retrieves the selected items as a tuple of strings. These
        # strings are the list indexes ('0' to whatever) of the items selected.
        # map applies the function specified in the 1st parameter to every item
        # from the 2nd parameter and returns a list of the results. So "items"
        # is now a list of integers
        items = map(int,self.l.curselection())

        # For however many values there are in "items":
        for i in range(len(items)):
            # Use each number as an index and get from the listbox the actual
            # text strings corresponding to each index, and append each to
            # the list "ichose".
            self.ichose.append(self.l.get(items[i]))
        # Write ichose to the textbox to display it.
        self.update_list()
        return self.ichose

    def update_list(self):
        self.selected_list.delete(0.0, END)
        self.selected_list.insert(0.0, self.ichose)


root=tk.Tk()
root.title('Listbox Multi-Capture')
root.geometry('200x340')
app=App(root)
root.mainloop()

print app.ichose

score 1 · Answer 2 · answered Apr 10 '13 at 15:18

# ----------------[ Listbox EXAMPLE ]----------------

    self.sarcCountries = (
        "Bangladesh",
        "India",
        "Pakistan",
        "Nepal",
        "Bhutan",
        "Sri Lanka",
        "Afghanistan"
    )

    self.listData = StringVar(value = self.sarcCountries)

    self.listbox = Listbox(
        master           = self,
        height           = 10,
        listvariable     = self.listData,
        selectmode       = MULTIPLE,
        selectbackground = "#BC80CC"
    )

    self.listbox.bind("<<ListboxSelect>>", self.OnListboxSelectionChanged)

    self.listbox.pack(fill = BOTH, expand = 0, padx = 10, pady = 10)
# ----------------[ Listbox EXAMPLE ]----------------


def OnListboxSelectionChanged(self, val):
    # NOTE: If your listbox's select mode is MULTIPLE, then you may use this portion of code
    selections = val.widget.curselection()

    print("---------------------------")

    if (selections != ()):
        for index in selections:
            print(self.sarcCountries[int(index)])

    print("---------------------------")

Problems in Python getting multiple selections from Tkinter listbox

2 Answers2