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Tkinter, update widgets real time if list is modified

Let say I've a list of widgets that are generated by tkinter uisng a loop (it's customtkinter in this case but since tkinter is more well known so I think it'd be better to make an example with it), each widgets lie in the same frame with different label text. Here is an example for the code:
x=0
self.scrollable_frame = customtkinter.CTkScrollableFrame(self, label_text="CTkScrollableFrame")
self.scrollable_frame.grid(row=1, column=2, padx=(20, 0), pady=(20, 0), sticky="nsew")
self.scrollable_frame.grid_columnconfigure(0, weight=1)
self.scrollable_frame_switches = []
for i in range(x,100):
switch = customtkinter.CTkSwitch(master=self.scrollable_frame, text=f"CTkSwitch {i}")
switch.grid(row=i, column=0, padx=10, pady=(0, 20))
self.scrollable_frame_switches.append(switch)
My question is, if the list that help generated those widgets change (in this case it's just a loop ranging from 0-100, might change the widgets text, list size..), what would be the best way for real time update the tkinter window contents?
Ps: I've tried to look for my answer from many places but as of right now, the best answer I can come up with is to update the whole frame with same grid but changed list content, I'll put it bellow. Is there any way better than this? Thank you

Like I said before, while the existing answer might work, it might be inefficient since you are destroying and creating new widgets each time there is a change. Instead of this, you could create a function that will check if there is a change and then if there is extra or less items, the changes will take place:
from tkinter import *
import random
root = Tk()
def fetch_changed_list():
"""Function that will change the list and return the new list"""
MAX = random.randint(5, 15)
# Create a list with random text and return it
items = [f'Button {x+1}' for x in range(MAX)]
return items
def calculate():
global items
# Fetch the new list
new_items = fetch_changed_list()
# Store the length of the current list and the new list
cur_len, new_len = len(items), len(new_items)
# If the length of new list is more than current list then
if new_len > cur_len:
diff = new_len - cur_len
# Change text of existing widgets
for idx, wid in enumerate(items_frame.winfo_children()):
wid.config(text=new_items[idx])
# Make the rest of the widgets required
for i in range(diff):
Button(items_frame, text=new_items[cur_len+i]).pack()
# If the length of current list is more than new list then
elif new_len < cur_len:
extra = cur_len - new_len
# Change the text for the existing widgets
for idx in range(new_len):
wid = items_frame.winfo_children()[idx]
wid.config(text=new_items[idx])
# Get the extra widgets that need to be removed
extra_wids = [wid for wid in items_frame.winfo_children()
[-1:-extra-1:-1]] # The indexing is a way to pick the last 'n' items from a list
# Remove the extra widgets
for wid in extra_wids:
wid.destroy()
# Also can shorten the last 2 steps into a single line using
# [wid.destroy() for wid in items_frame.winfo_children()[-1:-extra-1:-1]]
items = new_items # Update the value of the main list to be the new list
root.after(1000, calculate) # Repeat the function every 1000ms
items = [f'Button {x+1}' for x in range(8)] # List that will keep mutating
items_frame = Frame(root) # A parent with only the dynamic widgets
items_frame.pack()
for item in items:
Button(items_frame, text=item).pack()
root.after(1000, calculate)
root.mainloop()
The code is commented to make it understandable line by line. An important thing to note here is the items_frame, which makes it possible to get all the dynamically created widgets directly without having the need to store them to a list manually.
The function fetch_changed_list is the one that changes the list and returns it. If you don't want to repeat calculate every 1000ms (which is a good idea not to repeat infinitely), you could call the calculate function each time you change the list.
def change_list():
# Logic to change the list
...
calculate() # To make the changes
After calculating the time for function executions, I found this:
Widgets redrawn
Time before (in seconds)
Time after (in seconds)
400
0.04200148582458496
0.024012088775634766
350
0.70701003074646
0.21500921249389648
210
0.4723021984100342
0.3189823627471924
700
0.32096409797668457
0.04197263717651367
Where "before" is when destroying and recreating and "after" is only performing when change is needed.

So I've decided that if I want to click a button, that button should be able to update the list. Hence, I bind a non-related buttons in the widget to this function:
def sidebar_button_event(self):
global x
x=10
self.scrollable_frame.destroy()
self.after(0,self.update())
Which will then call for an update function that store the change value, and the update function will just simply overwrite the grid:
def update(self):
self.scrollable_frame = customtkinter.CTkScrollableFrame(self, label_text="CTkScrollableFrame")
self.scrollable_frame.grid(row=1, column=2, padx=(20, 0), pady=(20, 0), sticky="nsew")
self.scrollable_frame.grid_columnconfigure(0, weight=1)
self.scrollable_frame_switches = []
for i in range(x,100):
switch = customtkinter.CTkSwitch(master=self.scrollable_frame, text=f"CTkSwitch {i}")
switch.grid(row=i, column=0, padx=10, pady=(0, 20))
self.scrollable_frame_switches.append(switch)

How to know in what row is a label on a grid in Tkinter?

I have a table (grid) I'm creating, constituted of labels.
These labels are showing elements I'm adding to a list, therefore, when I add a new obj to the list, the table will grow, showing more labels.
My intent is that I can click a label and have it print the row of the table that that label is in.
import tkinter as tk
phrasesdb = []
def debug(event):
#this is where I'd have it print the row
#but how do I get it?
#for example, it the label I pressed was in the row 2, it'd print 2
print( ??? )
#Add obj to list
def addline():
##This creates new obj with values from the input fields, and inserts it in the list
newobj = {"text": newtext.get()} #This is getting the text from an Entery
phrasesdb.append(newobj)
##This shows new obj on the table
newesttext = tk.Label(tableframe, text=newobj["text"])
newesttext.grid(row=len(phrasesdb), column=1, sticky=tk.W)
newesttext.bind("<Double-Button-1>", debug)
I'm already able to show them in the table, and to have it recognize I'm pressing the correct label (tested with a simple print("yup, this is it") ), but I'm not being able to figure out how to access the row of the label I'm clicking.
I'm kinda new to python and especially tkinter, so sorry if this is a really easy question, but I'm not finding the answer anywhere else...

You can use the grid_info method which will return a dictionary of the item's grid attributes.
def debug(event):
widget = event.widget
info = widget.grid_info()
row = info['row']

If I understand your problem correctly using .grid_info()['row'] on the label you already received after clicking should return the result you need.

Beginner Python Keyboard GUI setup

I am beginning GUI in Python 3.5, and I am trying to setup a simple qwerty keyboard. Based on the examples, I tried the following code
from tkinter import Tk, Label, RAISED, Button, Entry
self.window = Tk()
#Keyboard
labels = [['q','w','e','r','t','y','u','i','o','p'],
['a','s','d','f','g','h','j','k','l'],
['z','x','c','v','b','n','m','<']]
n = 10
for r in range(3):
for c in range(n):
n -= 1
label = Label(self.window,
relief=RAISED,
text=labels[r][c])
label.grid(row=r,column=c)
continue
This gives me the first row, but it does not return anything else. I tried simply using 10 as the range, which created the first two rows of the keyboard, but it still did not continue onto the last row.

Your issue is in the line n -= 1. Every time a label is created, you make n one less- after the first whole row, n==0, and thus the range is 0>0, and ranges never include the high bound- for c in range(0) will just drop from the loop (as it has looped through all the nonexistent contents).
A better solution involves iterating through the lists instead of through the indexes- for loops take any iterable (list, dictionary, range, generator, set, &c.);
for lyst in labels:
# lyst is each list in labels
for char in lyst:
# char is the character in that list
label = Label(... text=char) # everything else in the Label() looks good.
label.grid(...) # You could use counters for this or use ennumerate()-ask if you need.
# The continue here was entirely irrelevant.

Is this what you want it to do? Let me know if you need me to explain it further but basically what I'm doing is first filling the columns in each row. So row remains 0 and then as I loop through the column (the inner list) I fill in each of the keys, then on to the next row and etc.
from tkinter import Tk, Label, RAISED, Button, Entry
window = Tk()
#Keyboard
labels = [['q','w','e','r','t','y','u','i','o','p'],
['a','s','d','f','g','h','j','k','l'],
['z','x','c','v','b','n','m','<']]
for r in labels:
for c in r:
label = Label(window, relief=RAISED, text=str(c))
label.grid(row=labels.index(r), column=r.index(c))
window.mainloop()

Programatically add and remove tkinter python labels causes IndexError: list index out of range

Sorry for the vague title but I didn't know how to explain myself better. Basically what I try to do in tkinter here is adding and removing labels. The label value gets updated so that I always have an increment of 1 even though I deleted a label in the beginning. If I generate labels and delete them from the bottom up I have no problems but it I delete one from the middle and then try to clean my list I get an error:
Exception in Tkinter callback
Traceback (most recent call last):
File "/opt/local/Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/lib-tk/Tkinter.py", line 1536, in __call__
return self.func(*args)
File "/Users/XXXX/Helper/development/dynamicListLabels.py", line 21, in <lambda>
labelList[index].append(ttk.Button(root, text="Remove", command=lambda: removeLabel(labelList[index][0], index)))
IndexError: list index out of range
My python code looks like this:
#!/usr/bin/python
from Tkinter import *
import ttk
def removeLabel(labelToRemove, bla):
labelList[labelToRemove.get()][1].destroy()
labelList[labelToRemove.get()][2].destroy()
del labelList[labelToRemove.get()]
for label in labelList:
index = labelList.index(label)
label[0].set(index)
def addNewLabel():
labelList.append([IntVar()])
index = len(labelList) - 1
labelList[index][0].set(index)
labelList[index].append(ttk.Label(root, textvariable=labelList[index][0]))
labelList[index].append(ttk.Button(root, text="Remove", command=lambda: removeLabel(labelList[index][0], index)))
labelList[index][1].grid(column=0)
labelList[index][2].grid(column=1, row=labelList[index][1].grid_info()['row'])
root = Tk()
labelList = []
ttk.Button(root, text="add label", command=addNewLabel).grid(column=1, row=0)
root.mainloop()
And my GUI looks like this:
Thanks for your help!

Design
The main problem comes when dealing with different indexes. Trying to manipulate them carefully leads to complicated operations resulting in a long and inefficient code. To remedy to this problem, we simply get rid of them and take advantage of the label class variable Tkinter.IntVar() you already are using. This gives us full control of the labels and associated widgets.
An other efficient decision to take that prevents from getting lot of headache is to attach each (label, button) couple widgets to a unique Tkinter.Frame() instance. This offers the advantage of deleting the frame using destroy() method leading automatically to the destruction of the widgets it contains. In the same time, this keeps the look of your GUI and makes your it scalable as it offers you the possibility to add more widgets.
Designing addNewLabel()
There is nothing new here compared to your original code except, as I said in 2. each (label, button) couple will be drawn into a single and unique Tkinter.Frame() instance. Of course, the list frames must be declared global in this method.
Designing removeLabel()
From 1. the only argument we need to pass to removeLabel() is the Tkinter variable (var in the code below) inherent to the label we want to get rid of.
We need then to loop over list of frames (frames in the code below) using winfo_children() to seek for the label which has the text variable we are looking for.
Note that because I draw the label before the button inside individual frames, winfo_children() returns as first widget list element the label
winfo_children():
Returns a list containing the path names of all the children of window. Top-level windows are returned as children of their logical
parents. The list is in stacking order, with the lowest window first,
except for Top-level windows which are not returned in stacking order.
Use the wm stackorder command to query the stacking order of Top-level
windows.
This is why it is correct to write : if frame.winfo_children()[0].var == var and destroy the frame that contains the label which satisfies this condition.
Solution
Here is the program. I commented the lines which I think deserve to be commented:
'''
Created on Jun 25, 2016
#author: billal begueradj
'''
from Tkinter import *
import ttk
def removeLabel(var):
global frames
z = -1
# Loop over the list of rames
for frame in frames:
z = z + 1
# Check the text variable of the label of this frame
if frame.winfo_children()[0].var == var:
# Destroy the related frame
frame.destroy()
# Update the size of the list of frames
frames = frames[:z] + frames[z+1:]
# Do not forget to always rest this flag back to -1
z = -1
# Update the labels' numbers
r = 0
for frame in frames:
frame.winfo_children()[0].var.set(r)
r = r + 1
def addNewLabel():
global frames, i
var = IntVar()
frame = Frame(root)
i = i + 1
frame.grid(row=i, column=0)
var.set(len(frames))
l = ttk.Label(frame, textvariable=var)
l.grid(row=0, column=0)
l.var = var
b = ttk.Button(frame, text="Remove", command=lambda: removeLabel(var))
b.grid(row=0, column=1)
frames.append(frame)
if __name__ == '__main__':
root = Tk()
frames = []
i = 1
ttk.Button(root, text="add label", command=addNewLabel).grid(column=0, row=0)
root.mainloop()
Demo
Let us create 6 labels:
Now let us delete the label number 3. You can see that the numbering of the labels is automatically updated:
Now let us add a new label. You can see the newly added label has a number which is consecutive to the last existing label number in the list:
Note that the length of the list is updated all the time as you wanted.

Python - arrays of tkinter widgets changing with radiobutton clicks

I'm working on a GUI in Python using tkinter. I'm reading a text file in and creating GUI elements dynamically based on the lines in the text file. I have an array for each of my element types, which include labels, radiobutton variables (StringVars), and colored circles (drawn with create_oval). My goal is that when the user changes a radiobutton from "not assigned" to "in" or "out", the colored circle on that line will change from yellow to green. Here's how the GUI looks after the text file has been read in:
Item 1: (o) in () out () not assigned (G)
Item 2: () in () out (o) not assigned (Y)
Currently, I have a trace on the radiobutton StringVars so that I can call a method whenever one of the buttons is changed. My problem is figuring out which radiobutton was changed so that I can change the color of the circle on that line...
I'm currently going the route of duplicating the whole radiobutton StringVar array into a temp global array. When the trace function is called, I compare the temp array with what's currently in the array to figure out where the change is. I duplicate the array with: temp_radiobutton_vars = list(radiobutton_vars), but I'm not sure if this is the right route. My temp list and the current list always show the same results when I get() the StringVar, even after I changed the button. Any ideas on how to fix this, or maybe there's a better method to do what I'm looking to do...
Sorry for the long and not great explanation. If anyone needs more info or snippets of code, let me know. Thanks!

There are many ways to solve this problem. Since you are already using variable traces, perhaps the simplest solution is to pass the index of the canvas item to the callback. You can use lambda or functools.partial for this task. You could also not use variable traces, but instead, associate a command with each radiobutton. In both cases you simply need to tell the callback which index to operate on.
In the following example, the callback takes a reference to a variable and the index to the canvas item. It fetches the value, looks up the color in a table, and then configures the canvas item:
def on_radiobutton(var, index):
value = var.get()
color = {"in": "green", "out": "red", "unassigned": "yellow"}
self.canvas.itemconfigure(index, fill=color[value])
This is how the trace is set up using lambda (note that name1, name2 and op are automatically sent by tkinter for every trace):
var = tk.StringVar()
rb0 = tk.Radiobutton(..., variable=var, value="in", text="in")
rb1 = tk.Radiobutton(..., variable=var, value="out", text="out")
rb2 = tk.Radiobutton(..., variable=var, value="unassigned", text="not assigned")
var.trace("w", lambda name1, name2, op, index=i, var=var:
on_radiobutton(var, index))

It sounds like you have the wrong idea with Radiobuttons. All "connected" Radiobuttons should have the same variable value; in this way, you can call theVariable.get() and compare that with the value of each Radiobutton; you shouldn't need a reference to every Radiobutton; nor should you have a StringVar for each Radiobutton, only each line.
Edit: I've expanded my example to show how this would work for more than one line. All that changed is now I check which line I have passed in my callback, and using that I know which line to update (in your case, which canvas to color). It's just some 2D list processing to check which Radiobutton is selected based upon which line is issuing the callback.
from Tkinter import *
root = Tk()
root.geometry("300x200+500+400")
lines = [StringVar(), StringVar()]
strings = [["Hello", "Stack", "Overflow"], ["Whats", "Going", "On"]]
buttons = [[],[]]
l1 = Label(root, text = "Selection: ", justify = LEFT)
l1.grid(column = 0, row = 0, sticky = NW, padx = (0, 250))
l1.grid_propagate(False)
l2 = Label(root, text = "Selection: ", justify = LEFT)
l2.grid(column = 0, row = 4, sticky = NW, padx = (0, 250))
l2.grid_propagate(False)
def process(line):
global l1, l2, strings, lines
if line == lines[0]:
# Since lines[0] was passed in to the callback, we know to update line 0;
# take that line's label (or canvas in your case)
updateLine = 0
updateLabel = l1
else:
# Otherwise take the other line
updateLine = 1
updateLabel = l2
# These operations are performed within if/elif/else to show how you coul
# choose a different process for each Radiobutton: example, coloring a canvas differently
if lines[updateLine].get() == strings[updateLine][0]:
# This means the first button of whatever line was selected
updateLabel.config(text = "Selection: %s" %strings[updateLine][0])
elif lines[updateLine].get() == strings[updateLine][1]:
# This means the second button of whatever line was selected
updateLabel.config(text = "Selection: %s" %strings[updateLine][1])
else:
# You get the idea
updateLabel.config(text = "Selection: Bet you thought I'd say %s" %strings[updateLine][2])
# Must have a seperate row number because with multiple lines, we can't simply use 'i' or 'j'
rowNum = 1
for i in range(len(lines)):
for j in range(len(strings[i])):
buttons[i].append(Radiobutton(root, text = strings[i][j], variable = lines[i], value = strings[i][j], command = lambda line = lines[i]: process(line)))
buttons[i][j].grid(column = 0, row = rowNum, sticky = NW)
rowNum +=1
rowNum += 2
root.mainloop()