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How to display the label ( text) value dynamically based on combo box selection value ( List box) in Tkinter?

I am new to tkinter application. The below code is working fine. Please help how to implement mentioned features.
The dynamic value should be displayed above clear button or below the combo box ( Used pack is bottom )- Now working
Clear the label value on combo box selection.
import tkinter as tk
from tkinter import ttk
from tkinter import *
from datetime import datetime
# root window
root = tk.Tk()
root.geometry("500x350")
root.resizable(False, False)
root.title('Test')
# Log Generator in frame
Generator = tk.Frame(root)
Generator.pack(padx=10, pady=10, fill='x', expand=True)
def clear():
combo.set('')
# Function to print the index of selected option
# in Combobox
def get_log_file_name(*arg):
date_Value = datetime.now().strftime("%Y_%m_%d_%I%M%S")
output_file_name_value = "Log_"+date_Value
if var.get() == "apple":
Label(Generator, text="The value at index: "+output_file_name_value+".txt", font=('Helvetica 12')).pack()
else:
Label(Generator, text="The value at index: "+output_file_name_value+".html", font=('Helvetica 12')).pack()
# Define Tuple of months
months = ('apple','banana')
# Create a Combobox widget
label = ttk.Label(Generator, text="Selection_Option:",font=('Helvetica', 10, 'bold'))
label.pack(fill='x', expand=True)
var = StringVar()
combo = ttk.Combobox(Generator, textvariable=var)
combo['values'] = months
combo['state'] = 'readonly'
combo.pack(padx=5, pady=5)
# Set the tracing for the given variable
var.trace('w', get_log_file_name)
# Create a button to clear the selected combobox
# text value
button = Button(Generator, text="Clear", command=clear)
button.pack(side=left)
# Make infinite loop for displaying app on
# the screen
Generator.mainloop()

Clear the label value on combo box selection.
You need to capture the ComboboxSelect event to do that and the function to execute if captured
the function should be like this
What you want to do here, is to capture the combobox event, and then, do the label configuration when capturing it,
Below is the code to do the thing. and you can add code there.
def comboboxEventCapture(e=None):
label.configure(text='')
# Your code after resetting variables!
Here's the event capturing part
combo.bind("<<ComboboxSelect>>", comboboxEventCapture)
You can name the function whatever you want though.
Note that the arguement e is needed because if the event is captured, the event itself is passed as a parameter into the function, that is of no use here (unless you are going to do something with it, then use e.objname)

The dynamic value should be displayed above clear button
The second label could be outside of get_log_file_name() function.
And also configure inside function. So you don't do duplicate Label widget, naming Label2
Also the pack() must be split to prevent an error.
To clear Label2 use .configure(text='')
We will be using ttk. So don't do this from tkinter import *
Code:
import tkinter as tk
from tkinter import ttk
from datetime import datetime
root = tk.Tk()
root.geometry("500x350")
root.resizable(False, False)
root.title('Test')
Generator = tk.Frame(root)
Generator.pack(padx=10, pady=10, fill='x', expand=True)
def clear():
label2.configure(text='')
def get_log_file_name(*arg):
date_Value = datetime.now().strftime("%Y_%m_%d_%I%M%S")
output_file_name_value = "Log_"+date_Value
if var.get() == "apple":
label2.configure(text="The value at index: "+output_file_name_value+".txt", font=('Helvetica 12'))
else:
label2.configure(text="The value at index: "+output_file_name_value+".html", font=('Helvetica 12'))
# Define Tuple of months
months = ('apple','banana')
# Create a Combobox widget
label2 = ttk.Label(Generator)
label2.pack()
label = ttk.Label(Generator, text="Selection_Option:",font=('Helvetica', 10, 'bold'))
label.pack(fill='x', expand=True)
var = tk.StringVar()
combo = ttk.Combobox(Generator, textvariable=var)
combo['values'] = months
combo['state'] = 'readonly'
combo.pack(padx=5, pady=5)
# Set the tracing for the given variable
var.trace('w', get_log_file_name)
# Create a button to clear the selected combobox
# text value
button = ttk.Button(Generator, text="Clear", command=clear)
button.pack(side='left')
# Make infinite loop for displaying app on
# the screen
Generator.mainloop()
Screenshot for apple:
Screenshot for banana:
Screenshot to clear Label2:

Where do I make a mistake with this tkinter focus?

I made a tool to add multiple order numbers in our system. The first time a row of entry cells is placed the focus is where it should be. But the second time the focus is not in the new left cell. First I thought it has to do with using the tab key. But if I understand the code correct, I first execute the moving of the tab key and then execute the code. So the command to focus on the new left cell is last.
Where am I going wrong?
import tkinter as tk
from tkinter import ttk
# Create variables for later use
order_list = []
date_list = []
row_number = 0
active_order_entry = None
active_date_entry = None
def add_a_row_of_entry_cells():
global row_number
global active_order_entry
global active_date_entry
row_number += 1
order_entry = ttk.Entry()
order_entry.grid(row=row_number, column=0)
order_entry.focus()
date_entry = ttk.Entry()
date_entry.grid(row=row_number, column=1)
# Make these entries the active ones
active_order_entry = order_entry
active_date_entry = date_entry
# Add entries to a list
order_list.append(order_entry)
date_list.append(date_entry)
def tab_pressed(event):
if active_order_entry.get() != "" and active_date_entry.get() != "":
add_a_row_of_entry_cells()
else:
print("Order, date or both are not filled yet")
def button_pressed():
print("Button pressed")
# Create window
window = tk.Tk()
# Add function to the Tab key
window.bind("<Tab>", tab_pressed)
# Labels on top of the columns
label_order_number = tk.Label(window, text="Order", fg="#22368C")
label_order_number.grid(row=row_number, column=0)
label_date = tk.Label(window, text="Date", fg="#22368C")
label_date.grid(row=row_number, column=1)
# Create empty row
empty_row = tk.Label(window)
empty_row.grid(row=87, column=0)
# Create button
button = tk.Button(window, text="Add orders", command=lambda: button_pressed())
button.grid(row=98, column=0, columnspan=3)
# Create empty row
empty_row = tk.Label(window)
empty_row.grid(row=99, column=0)
# Add the first row
add_a_row_of_entry_cells()
window.mainloop()

How to get values of checkbuttons from for loop tkinter python

I am new to programming in tkinter and am very stuck on using checkbuttons. I have created multiple checkbuttons in one go, all with different text for each one and a different grid position. However I have no idea how to get the value of each button or how to even set it. I want to be able to get the state/value for each button and if it is checked, then another function is called. How do I set and call the value/state of each button? Can this be done in a for loop or do I have to create them individually?
def CheckIfValid(self, window):
Class = self.ClassChosen.get()
Unit = self.UnitChosen.get()
Topic = self.TopicChosen.get()
if Class == '' or Unit == '' or Topic == '':
tm.showinfo("Error", "Please fill in all boxes")
else:
QuestionData = OpenFile()
QuestionsList = []
for x in range (len(QuestionData)):
#if QuestionData[x][2] == Topic:
QuestionsList.append(QuestionData[x][0])
for y in range(len(QuestionsList)):
self.ButtonVal[y] = IntVar()
Checkbutton(window, text = QuestionsList[y], padx = 20, variable = self.ButtonVal[y]).grid(row = 12 + y, column = 2)
ConfirmSelection = Button(window, text = "Set Homework", command = lambda: SetHomeworkClass.ConfirmHomework(self)).grid()
print(variable.get()) #here I would like to be able to get the value of all checkbuttons but don't know how

You use the list of IntVars either called from a command= in the Checkbutton or in the Button. Don't know why you are calling another class's object, SetHomeworkClass.objectConfirmHomework(self). It doesn't look like that will work as you have it programmed, as that is another name space and the list of IntVars is in this name space, but that is another topic for another thread.
try:
import Tkinter as tk # Python2
except ImportError:
import tkinter as tk # Python3
def cb_checked():
# remove text from label
label['text'] = ''
for ctr, int_var in enumerate(cb_intvar):
if int_var.get(): ## IntVar not zero==checked
label['text'] += '%s is checked' % cb_list[ctr] + '\n'
root = tk.Tk()
cb_list = [
'apple',
'orange',
'banana',
'pear',
'apricot'
]
# list of IntVar for each button
cb_intvar = []
for this_row, text in enumerate(cb_list):
cb_intvar.append(tk.IntVar())
tk.Checkbutton(root, text=text, variable=cb_intvar[-1],
command=cb_checked).grid(row=this_row,
column=0, sticky='w')
label = tk.Label(root, width=20)
label.grid(row=20, column=0, sticky='w')
# you can preset check buttons (1=checked, 0=unchecked)
cb_intvar[3].set(1)
# show what is initially checked
cb_checked()
root.mainloop()

Deselecting from a listbox in Tkinter

I'm just wondering how I can deselect from a list box in thinter. Whenever I click on something in a list box, it gets highlighted and it gets underlined, but when I click off of the screen towards the side, the list box selection stays highlighted. Even when I click a button, the selection still stays underlined. For ex: in the example code below, I can't click off of the list box selection after clicking on one of them.
from tkinter import *
def Add():
listbox.insert(END, textVar.get())
root = Tk()
textVar = StringVar()
entry = Entry(root, textvariable = textVar)
add = Button(root, text="add", command = Add)
frame = Frame(root, height=100, width=100, bg="blue")
listbox = Listbox(root, height=5)
add.grid(row=0, column=0, sticky=W)
entry.grid(row=0, column=1, sticky=E)
listbox.grid(row=1, column=0)
frame.grid(row=1, column=1)
root.mainloop()

Yes, that's the normal behavior of the listbox. If you want to change that you could call the clear function every time the listbox left focus:
listbox.bind('<FocusOut>', lambda e: listbox.selection_clear(0, END))

Use the selectmode parameter on the Listbox widget.
You can click the selected item again and it will clear the selection.
See the effbot link:
http://effbot.org/tkinterbook/listbox.htm
listbox = Listbox(root, height=5, selectmode=MULTIPLE)

I have managed to create the functionality needed within the Listbox widget so that when a user clicks either back on the same item in the Listbox or elsewhere on screen the currently selected item is deselected. The solution came out to be quite simple.
Firsly I created a binding so that when the left mouse button is pressed anywhere on the window a function to deselect the list box is executed.
root.bind('<ButtonPress-1>', deselect_item)
I then created a variable to store the value of the last listbox item to be selected and initialised its value to None
previous_selected = None
Then I defined the function to deselect the listbox as follows. Firsly the new item (what item the user has just clicked on) is selected and compared to the previously selected item. If this is true then the user has clicked on an already highlighted item in the listbox and so the listbox's selection is cleared, removing the selected item. Finally, the function updates the previously selected box to the current selected box.
def deselect_item(event):
if listbox.curselection() == previous_selected:
listbox.selection_clear(0, tkinter.END)
previous_selected = listbox.curselection()
A full working example of this (in python 3.8.0) is shown below:
import tkinter
class App(tkinter.Tk):
def __init__(self):
tkinter.Tk.__init__(self)
self.previous_selected = None
self.listbox = tkinter.Listbox(self)
self.bind('<ButtonPress-1>', self.deselect_item)
self.listbox.insert(tkinter.END, 'Apple')
self.listbox.insert(tkinter.END, 'Orange')
self.listbox.insert(tkinter.END, 'Pear')
self.listbox.pack()
def deselect_item(self, event):
if self.listbox.curselection() == self.previous_selected:
self.listbox.selection_clear(0, tkinter.END)
self.previous_selected = self.listbox.curselection()
app = App()
app.mainloop()

How to add Autoscroll on insert in Tkinter Listbox?

I'm using a listbox (with scrollbar) for logging:
self.listbox_log = Tkinter.Listbox(root, height = 5, width = 0,)
self.scrollbar_log = Tkinter.Scrollbar(root,)
self.listbox_log.configure(yscrollcommand = self.scrollbar_log.set)
self.scrollbar_log.configure(command = self.listbox_log.yview)
Now, when I do:
self.listbox_log.insert(END,str)
I want the inserted element to be selected. I've tried:
self.listbox_log.selection_anchor(END)
but that doesn't work... Please suggest a solution...

AFAIK the ScrollBar widget doesn't have an auto-scroll feature, but it can be easily implemented by calling the listBox's yview() method after you insert a new item. If you need the new item to be selected then you can do that manually too using the listbox's select_set method.
from Tkinter import *
class AutoScrollListBox_demo:
def __init__(self, master):
frame = Frame(master, width=500, height=400, bd=1)
frame.pack()
self.listbox_log = Listbox(frame, height=4)
self.scrollbar_log = Scrollbar(frame)
self.scrollbar_log.pack(side=RIGHT, fill=Y)
self.listbox_log.pack(side=LEFT,fill=Y)
self.listbox_log.configure(yscrollcommand = self.scrollbar_log.set)
self.scrollbar_log.configure(command = self.listbox_log.yview)
b = Button(text="Add", command=self.onAdd)
b.pack()
#Just to show unique items in the list
self.item_num = 0
def onAdd(self):
self.listbox_log.insert(END, "test %s" %(str(self.item_num))) #Insert a new item at the end of the list
self.listbox_log.select_clear(self.listbox_log.size() - 2) #Clear the current selected item
self.listbox_log.select_set(END) #Select the new item
self.listbox_log.yview(END) #Set the scrollbar to the end of the listbox
self.item_num += 1
root = Tk()
all = AutoScrollListBox_demo(root)
root.title('AutoScroll ListBox Demo')
root.mainloop()

try to do it in this way. (I have copied from another question: How to auto-scroll a gtk.scrolledwindow?) It works fine for me.
def on_TextOfLog_size_allocate(self, widget, event, data=None):
adj = self.scrolled_window.get_vadjustment()
adj.set_value( adj.upper - adj.page_size )