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tkinter throws error using a variable for button name to set state

I want to pass a button name to tkinter as a variable. This method works for Text fields, but not for buttons in my code.
I am building a gui app and I want to have a generic clear function that zaps a text entry field and resets a button from NORMAL to DiSABLED.
There are multiple buttons and fields, hence the desire to make this generic.
For the code I have, the buttons are present with the exception of clear all.
I am setting the variable w_button to the specific name of the (existing) button based on what is passed to the function.
def switch_clear(elem_type):
if elem_type == 'scn':
w_button = 'b_clear_scn'
clear_field = 'scn_file_entry'
print ('scenario')
elif elem_type == 'sol2':
w_button = 'b_clear_sol2'
clear_field = 'sol2_file_entry'
print ('sol2')
elif elem_type == 'mdl':
w_button = 'b_clear_mdlList'
clear_field = 'mdlList_file_entry'
print ('mdl')
elif elem_type == 'all':
print ('clear all TBD')
return()
if w_button["state"] == NORMAL:
clear_field.delete(0, END)
w_button["state"] = DISABLED
return()
Here's what happens:
C:\utils>my_frame3.py
scenario
Traceback (most recent call last):
File "C:\utils\my_frame3.py", line 127, in <module>
b_clear_scn = Button(first_frame, text = "Clear scenario", command = switch_clear('scn'), height = 2, state=DISABLED)
File "C:\utils\my_frame3.py", line 100, in switch_clear
if w_button["state"] == NORMAL:
TypeError: string indices must be integers
C:\utils>
I realize I could duplicate and push the clear operations into the if/elif statements, and I may have to live with that but - is it possible to reference buttons as variables? How can I do this?
Complete code as requested below. The preview is a mess despite using the code widget, but in my file lines are correctly formatted (notepad++). Tx
import os, sys
from tkinter import *
from tkinter import messagebox
from tkinter import filedialog
root2 = Tk()
root2.title('Model Processing')
root2.geometry('{}x{}'.format(512, 400))
# colors
color1 = 'light cyan'
color2 = 'gold'
color3 = 'RosyBrown1'
color4 = 'lavender'
color5 = 'linen'
bg_color = 'azure'
# number of items to process; until >1 OK is disabled; if >1 OK is enabled TBD
l_to_do = [] # items to process; scn, sol2, modelList, installed models
# functions/commands
def callback():
print ('A button was clicked.')
return;
def my_exit():
result = messagebox.askquestion("Cancel Model Processing", "Are you sure?", icon='warning')
if result == 'yes':
root2.quit()
else: # user changed mind
pass
def choose_import_file(str_ftype):
which_field = ''
which_clear_btn = ''
ftype = str_ftype
mdl_opts = {}
if ftype == 'scn':
title_msg = 'Choose a scenario file'
mdl_opts['filetypes'] = [('Supported types', ('.scn')),
('scenario files',('.scn'))]
which_field = scn_file_entry
which_clear_btn = 'b_clear_scn'
elif ftype == 'sol2':
title_msg = 'Choose a SOL2 file'
mdl_opts['filetypes'] = [('Supported types', ('.txt')),
('sol2 files',('.txt'))]
which_field = sol2_file_entry
elif ftype == 'mdllist':
title_msg = 'Choose a ModelList file'
print ('TBD: ModelList file')
file_input = filedialog.askopenfilename(title = title_msg, **mdl_opts)
if file_input == '':
print ('error or cancelled by user')
return
else:
f_inp_file = os.path.basename(file_input)
f_inp_file_base = str(file_input.split('.')[0])
f_inp_file_ext = str.lower(str(file_input.split('.')[1]))
f_inp_d_name = os.path.dirname(file_input)
print('File chosen:', f_inp_file_base)
# populate scenario file field
which_field.insert(INSERT,file_input)
which_clear_btn["state"] = NORMAL
# define appropriate clear button active
# define_clear_btn.configure(state = ACTIVE)
return
def switch_clear(elem_type):
if elem_type == 'scn':
if b_clear_scn["state"] == NORMAL:
scn_file_entry.delete(0, END)
b_clear_scn["state"] = DISABLED
elif elem_type == 'sol2':
f b_clear_sol2["state"] == NORMAL:
clear_field = 'sol2_file_entry'
b_clear_sol2["state"] = DISABLED
elif elem_type == 'mdl':
if b_clear_mdlList["state"] == NORMAL:
clear_field = 'mdlList_file_entry'
b_clear_mdlList["state"] = DISABLED
elif elem_type == 'all':
print ('clear all TBD')
return()
return()
# create all of the main containers
first_frame = Frame(root2, bg=color5, width = 512, height=90, pady=10)
second_frame = Frame(root2, bg=color5, width = 512, height=90, pady=10)
third_frame = Frame(root2, bg=color5, width=512, height=90, pady=10)
fourth_frame = Frame(root2, bg=color5, width = 512, height = 90, pady=10)
# layout all of the main containers
root2.grid_rowconfigure(3, weight=1)
root2.grid_rowconfigure(2, weight=1)
root2.grid_rowconfigure(1, weight=1)
root2.grid_columnconfigure(0, weight=1)
first_frame.grid(row=0, sticky="ew")
second_frame.grid(row=1, sticky="ew")
third_frame.grid(row=2, sticky="ew")
fourth_frame.grid(row = 3, sticky="e")
# create the widgets for the first frame
#scn_label = Label(first_frame, text = 'Scenario file')
scn_file_entry = Entry(first_frame, background=bg_color, width = 50)
b_choose_scn = Button(first_frame, text = "Choose a scenario..", command = lambda: choose_import_file('scn'), height = 2)
b_clear_scn = Button(first_frame, text = "Clear scenario", command = switch_clear('scn'), height = 2, state=DISABLED)
# layout the widgets in the first frame
#scn_label.grid(row = 0, column = 0, padx = (10,50), pady=5)
scn_file_entry.grid(row = 0, column = 1, padx = (10,10))
b_choose_scn.grid(row=0, column=0, padx = (10,10), sticky=W)
b_clear_scn.grid(row=2, column=0, padx = (10,10), sticky=W)
# second frame
# sol2_label = Label(second_frame, text = 'Sol2 file')
sol2_file_entry = Entry(second_frame, background=bg_color, width = 50)
b_choose_sol2 = Button(second_frame, text = "Choose SOL2 file..", command = lambda: choose_import_file('sol2'), height = 2)
b_clear_sol2 = Button(second_frame, text = "Clear SOL2", command = switch_clear('sol2'), height = 2, state=DISABLED)
# layout the widgets in the second frame
# sol2_label.grid(row = 0, column = 0, padx = (10,50), pady=5)
sol2_file_entry.grid(row = 0, column = 1, padx = (10,10), sticky=EW)
b_choose_sol2.grid(row=0, column=0, padx = (10,10), sticky=W)
b_clear_sol2.grid(row=2, column=0, padx = (10,10), sticky=W)
# third frame
# mdlList_label = Label(third_frame, text = 'ModelList.txt file')
mdlList_file_entry = Entry(third_frame, background=bg_color, width = 50)
b_choose_mdlList = Button(third_frame, text = "Choose ModelList.txt file..", command = callback, height = 2)
b_clear_mdlList = Button(third_frame, text = "Clear ModelList", command = callback, height = 2, state=DISABLED)
# layout the widgets in the third frame
#mdlList_label.grid(row = 0, column = 0, padx = (10,10), pady=5, sticky = 'ns')
mdlList_file_entry.grid(row = 0, column = 1, padx = (10,10), sticky=EW)
b_choose_mdlList.grid(row=0, column=0, padx = (10,10), sticky=W)
b_clear_mdlList.grid(row=2, column=0, padx = (10,10), sticky=W)
#####################################################################
# create bottom widgets
#####################################################################
clear_all = Button(fourth_frame, text='Clear All', padx = '5', command = callback, height = 2, state=DISABLED)
ok_btn = Button(fourth_frame, text='OK', padx = '5', command = callback, height = 2, state=DISABLED)
cancel_btn = Button(fourth_frame, text='Cancel', height = 2, padx = '12', command = my_exit)
#####################################################################
# layout the bottom widgets
#####################################################################
clear_all.grid(row = 0, column = 2, sticky = 'e')
ok_btn.grid(row = 0, column = 3, sticky = 'e')
cancel_btn.grid(row = 0, column = 4, sticky = 'e')
# commands/bindings
root2.mainloop()

I believe this is what you are trying to do. The below is fully commented with explanations. switch_clear becomes entirely unnecessary with this method. The buttons directly clear their corresponding entry in their command, and Entry validation takes care of the corresponding button state.
Note: I wrote all of this before you posted your full code
import tkinter as tk
root = tk.Tk()
root.geometry('400x400')
#toggle the state of buttons based on entry text length
def toggle_button(name, text):
global btn_switch
btn_switch[name]['state'] = 'normal' if len(text) else 'disabled'
return True
#to hold the buttons so they are easy to position
#just for this example
buttons = tk.Frame(root)
buttons.pack(side='top', anchor='nw')
#create a tcl wrapper for the validate command
vcmd = tk.Widget.register(root, toggle_button)
#mock-up of your entries ~ validate on key press. send widget name and full text to vcmd
scn_file_entry = tk.Entry(root, width=20)
scn_file_entry.configure(validate="key", validatecommand=(vcmd, '%W', '%P'))
scn_file_entry.pack(side='left', anchor='nw')
sol2_file_entry = tk.Entry(root, width=20)
sol2_file_entry.configure(validate="key", validatecommand=(vcmd, '%W', '%P'))
sol2_file_entry.pack(side='left', anchor='nw')
mdlList_file_entry = tk.Entry(root, width=20)
mdlList_file_entry.configure(validate="key", validatecommand=(vcmd, '%W', '%P'))
mdlList_file_entry.pack(side='left', anchor='nw')
#mock-up of your buttons ~ delete the entry text in a lambda and let entry validation handle the button state
b_clear_scn = tk.Button(buttons, text="scn", state='disabled')
b_clear_scn.configure(command=lambda: scn_file_entry.delete(0, 'end'))
b_clear_scn.pack(side='left', anchor='nw')
b_clear_sol2 = tk.Button(buttons, text="sol2", state='disabled')
b_clear_sol2.configure(command=lambda: sol2_file_entry.delete(0, 'end'))
b_clear_sol2.pack(side='left', anchor='nw')
b_clear_mdlList = tk.Button(buttons, text="mdl", state='disabled')
b_clear_mdlList.configure(command=lambda: mdlList_file_entry.delete(0, 'end'))
b_clear_mdlList.pack(side='left', anchor='nw')
#create a dictionary of 'widget name':corresponding button, for toggle_button to reference
btn_switch = {
f'{scn_file_entry}':b_clear_scn,
f'{sol2_file_entry}':b_clear_sol2,
f'{mdlList_file_entry}':b_clear_mdlList,
}
root.mainloop()

Creating and Getting values from tkinter check boxes using for loop

This code is a part of my project in which I have to manage the attendance of 50 (or more) students.
The thing I want is that all the checkboxes should initially be 'checked' (showing the present state) and when I uncheck random checkboxes (to mark the absent) and click the Submit button (yet to be created at the bottom of the window), I should get a list with 'entered date' as first element and the roll numbers i.e. 2018-MC-XX as other elements.
For example: ['01/08/2020', '2018-MC-7', '2018-MC-11', '2018-MC-23', '2018-MC-44']
Actually my plan is when I will get a list I will easily write it to a text file. Also, if there is another way of creating multiple scrollable checkboxes without packing them inside a canvas then please do tell!
from tkinter import *
from tkcalendar import DateEntry
root = Tk()
root.geometry('920x600+270+50')
root.minsize(920,600)
Attendance_frame = Frame(root) ### Consider it a Main Frame
Attendance_frame.pack()
attendaceBox = LabelFrame(Attendance_frame, text = 'Take Attendance', bd = 4, relief = GROOVE, labelanchor = 'n',font = 'Arial 10 bold', fg = 'navy blue', width = 850, height = 525) # A Label Frame inside the main frame
attendaceBox.pack_propagate(0)
attendaceBox.pack(pady = 15)
dateFrame = Frame(attendaceBox) # A small frame to accommodate date entry label & entry box
dateFrame.pack(anchor = 'w')
font = 'TkDefaultFont 10 bold'
date_label = Label(dateFrame, text = 'Enter Date : ', font = font).grid(row = 0, column = 0, sticky = 'w', padx = 10, pady = 10)
date_entry = DateEntry(dateFrame, date_pattern = 'dd/mm/yyyy', showweeknumbers = FALSE, showothermonthdays = FALSE)
date_entry.grid(row = 0, column = 1, sticky = 'w')
noteLabel = Label(attendaceBox, text = 'Note: Uncheck the boxes for absentees').pack(anchor = 'w', padx = 10, pady = 5)
canvas = Canvas(attendaceBox, borderwidth=0, background="#ffffff")
checkFrame = Frame(canvas, width = 100, height = 50)
vsb = Scrollbar(canvas, orient="vertical", command=canvas.yview)
canvas.configure(yscrollcommand=vsb.set)
vsb.pack(side="right", fill="y")
canvas.pack(side="left", fill="both", expand=True)
canvas.pack_propagate(0)
canvas.create_window((4,4), window=checkFrame, anchor="nw")
def onFrameConfigure(canvas):
'''Reset the scroll region to encompass the inner frame'''
canvas.configure(scrollregion=canvas.bbox("all"))
checkFrame.bind("<Configure>", lambda event, canvas=canvas: onFrameConfigure(canvas))
for i in range(0,51): # A loop to create Labels of students roll numbers & names
c = Checkbutton(checkFrame, text = f"{'2018-MC-'+str(i+1)} Student {i+1}")
c.grid(row = i, column = 0, padx = 10, sticky = 'w')
mainloop()

First you need StringVar for each Checkbutton in order to get the state of the Checkbuttons later. Then you can use a list to hold the StringVars so that you can access them later. You can set the onvalue of the checkbuttons to the roll number associated to them.
Also you can use Text widget instead of Canvas+Frame. Below is an example:
import tkinter as tk
root = tk.Tk()
frame = tk.Frame(root)
frame.pack()
text = tk.Text(frame, width=40, height=20)
text.pack(side=tk.LEFT, fill=tk.BOTH)
vars = []
for i in range(51):
rollnum = '2018-MC-'+str(i+1)
var = tk.StringVar(value=rollnum)
cb = tk.Checkbutton(text, text=rollnum, variable=var, onvalue=rollnum, offvalue='', bg='white')
text.window_create('end', window=cb)
text.insert('end', '\n')
vars.append(var)
vsb = tk.Scrollbar(frame, orient=tk.VERTICAL, command=text.yview)
vsb.pack(side=tk.RIGHT, fill=tk.Y)
text.config(yscrollcommand=vsb.set)
def submit():
# extract roll numbers for checked checkbuttons
result = [var.get() for var in vars if var.get()]
print(result)
tk.Button(root, text='Submit', command=submit).pack()
root.mainloop()

Tkinter buttons not performing command [duplicate]

This question already has answers here:
Why is my Button's command executed immediately when I create the Button, and not when I click it? [duplicate]
(5 answers)
Closed 4 years ago.
I am trying to create a counter for Jeopardy so that my Mom and I can keep score. Currently the program that I am creating is assigning the values to variables and then not performing the command when I press the button in the window. I am running Python 2.7.13.`
import Tkinter as tk
root = tk.Tk()
root.title("Jeopardy Scores")
def ChangeScore(User,Value):
if User == 1:
Score = int(JScore.get())
JScore.set(Score + Value)
#J = JScore.get()
#print J
#SayHi()
else:
Score = int(MScore.get())
MScore.set(Score + Value)
#M = MScore.get()
#print M
#SayHi()
#def SayHi(*args):
#print 'hi'
MainFrame = tk.Frame(root)
MainFrame.grid(column=0, row=0)
MainFrame.columnconfigure(0, weight=1)
MainFrame.rowconfigure(0, weight=1)
JScore = tk.StringVar()
MScore = tk.StringVar()
JScore.set(0)
MScore.set(0)
JL = tk.Label(MainFrame, text = "Joey's Score", padx = 10, pady = 2)
JL.config(bg = 'blue', fg = 'yellow', font = ('Arial',30, 'bold'))
JL.grid(column = 0, row = 0)
ML = tk.Label(MainFrame, text = "Mom's Score", padx = 10, pady = 2)
ML.config(bg = 'blue', fg = 'yellow', font = ('Arial',30, 'bold'))
ML.grid(column = 1, row = 0)
JSS = tk.Label(MainFrame, textvariable=JScore ,padx = 122)
JSS.config(bg = 'blue', fg = 'yellow', font = ('Arial',30, 'bold'))
JSS.grid(column = 0, row = 1)
MSS = tk.Label(MainFrame, textvariable = MScore,padx = 122)
MSS.config(bg = 'blue', fg = 'yellow', font = ('Arial',30, 'bold'))
MSS.grid(column = 1, row = 1)
for i in range(1,6):
Score = tk.IntVar()
Score.set(i*200)
Score1 = 200*i
JButton = tk.Button(MainFrame, textvariable = Score, command =
ChangeScore(1,Score1))
JButton.grid(column = 0, row = 1+i)
MButton = tk.Button(MainFrame, textvariable = Score, command =
ChangeScore(2,Score1))
MButton.grid(column = 1, row = 1+i)
JButton = tk.Button(MainFrame, text = '400', command = ChangeScore(1,400))
JButton.grid(column = 0, row = 7)
root.mainloop()
The code runs and produces this Window
Note that no buttons have been pressed when the picture was taken. It appears that all the buttons are 'being pressed' when the code runs and then nothing happens when i press the buttons afterwards.
I have no experience with Tkinter beyond the small information that has allowed me to do this and I have a bit more experience with Python. I am mainly doing this as an excerise for myself to improve my coding and to acutally use for Jeopardy!. Any help would be appreciate

Here the command parameter for Button should be a callable. You should not call the function yourself and pass the return value to it. Instead, you provide a function that is to be called later.
So change you code to things like
command=lambda: ChangeScore(1, 400)
to create a lambda to be called later will solve the problem.

python tkinter - over writing label on button press

def button_pressed(item_name, item_price):
global lbl
for v1, v2 in zip(item_name, item_price):
item_values = '{} {}'.format(v1, v2)
sv = StringVar()
lbl = Label(shop_window, height="2", textvariable=sv, anchor = NW).grid(columnspan = 4)
sv.set(item_values)
# Create initial shopping cart window
shop_window = Tk()
shop_window.title('Welcome to the Outlet')
shop_window.geometry("1200x900")
shop_window.resizable(0, 0)
introduction_text = Label(shop_window, text = 'Welcome to the Shopping Outlet', font = ('Arial', 30))
electronics_button = Button(shop_window, text = 'Buy Electronics', font = ('Arial', 18), command = lambda:button_pressed(electronics_name, electronics_price))
books_button = Button(shop_window, text = 'Buy Books', font = ('Arial', 18), command = lambda:button_pressed(books_name, books_price))
kitchen_button = Button(shop_window, text = 'Buy Kitchen', font = ('Arial', 18), command = lambda:button_pressed(kitchen_name, kitchen_price))
monitors_button = Button(shop_window, text = 'Buy Kitchen', font = ('Arial', 18), command = lambda:button_pressed(monitors_name, monitors_price))
introduction_text.grid(row = 0, column = 0, columnspan = 4, sticky = N )
electronics_button.grid(row = 2, column = 0)
books_button.grid(row = 2, column = 1)
kitchen_button.grid(row = 2, column =2)
monitors_button.grid(row = 2, column = 3)
I've created this tk window to display a shopping list of 10 items per category. Each category has two list, item_name/item_price (they have been scraped off amazon.)
When I run the program I can press the button and the list will display properly but if I press it again it adds new labels to the end of the previously made labels. My questions would be how do I make the program overwrite previous labels for example. Press "Buy Electronics" creates my labels as required, but pressing "Buy Books" after adds more labels. I want to over write the "Buy Electronics" labels. I figured it would be some kind of global lbl but unsure.

You could create a frame for the labels
f = Frame(shop_window)
f.grid(row=3, column=0, columnspan=4)
Then in the callback function destroy all children of the frame and create new ones
def button_pressed(item_name, item_price):
for widget in f.winfo_children():
widget.destroy()
for v1, v2 in zip(item_name, item_price):
item_values = '{} {}'.format(v1, v2)
Label(f, height="2", text=item_values).pack()

see the on the example with function have created, to do that you need to overwrite before positioning the current one there by using lbl["text"] = sv
def button_pressed(item_name, item_price):
global lbl
for v1, v2 in zip(item_name, item_price):
item_values = '{} {}'.format(v1, v2)
# sv = StringVar()
lbl["text"] = sv
sv.set(item_values)
Then create you Label inside root and mainloop
shop_window = Tk()
sv = StringVar()
lbl = Label(shop_window, height="2", textvariable=sv, anchor = NW)
lbl.grid(columnspan = 4)
shop_window = Tk()

Unable to achieve wanted entry textBox alignment

HI i am trying to place the alignment of my Entry(Text Box) according to the image below. I tried everything, TOP BOTTOM LEFT RIGHT.
This is the alignment i want. Obtained from paint program*
Problem
Coding of tkinter
master = Tk.Tk() # Open up GUI connection
master.title('Program Application')
print "VSM activated input range first (X2 must be larger than X1)"
#Declare button and respective method
button = Tk.Button(text='VSM', command=VSM, fg="red")
button.config( height = 10, width = 80 )
button.pack() #pack is needed to display the button
bluebutton = Tk.Button(text="AGM Folder",command= lambda: Folder(0), fg="blue").pack(side = LEFT)
bluebutton = Tk.Button(text="VSM Folder",command= lambda: Folder(1), fg="blue").pack(side = RIGHT)
Label(text='Correct Range for Gradient\nX2 X1').pack(side=TOP,padx=10,pady=10)
entryX2 = Entry(master, width=10)
entryX2.pack(side=LEFT,padx=10,pady=10)
entryX1 = Entry(master,width=10)
entryX1.pack(side=RIGHT,padx=10,pady=10)
buttonGradient = Tk.Button(text='Input Range OP',command= lambda: Folder(2), fg="red").pack()
entryX2IP = Entry(master, width=10)
entryX2IP.pack(side=LEFT,padx=10,pady=10)
entryX1IP = Entry(master,width=10)
entryX1IP.pack(side=RIGHT,padx=10,pady=10)
btnGradientIP = Tk.Button(text='Input Range IP',command= lambda: Folder(2), fg="red").pack(side = TOP)
master.mainloop() # Continue loop till user close tab

Use Frame:
master = Tk.Tk() # Open up GUI connection
master.title('Program Application')
print "VSM activated input range first (X2 must be larger than X1)"
#Declare button and respective method
button = Tk.Button(text='VSM', command=VSM, fg="red")
button.config( height = 10, width = 80 )
button.pack() #pack is needed to display the button
bluebutton = Tk.Button(text="AGM Folder",command= lambda: Folder(0), fg="blue").pack(side = LEFT)
bluebutton = Tk.Button(text="VSM Folder",command= lambda: Folder(1), fg="blue").pack(side = RIGHT)
Label(text='Correct Range for Gradient\nX2 X1').pack(side=TOP,padx=10,pady=10)
################### Use 3 frames to contains entries, buttons.
frameX2 = Frame(master)
frameX2.pack(side=LEFT, expand=1, anchor=E)
entryX2 = Entry(frameX2, width=10)
entryX2.pack(side=TOP,padx=10,pady=10)
entryX2IP = Entry(frameX2, width=10)
entryX2IP.pack(side=TOP,padx=10,pady=10)
frameButton = Frame(master)
frameButton.pack(side=LEFT)
Tk.Button(frameButton, text='Input Range OP',command= lambda: Folder(2), fg="red").pack(padx=10, pady=10)
Tk.Button(frameButton, text='Input Range IP',command= lambda: Folder(2), fg="red").pack(padx=10, pady=10)
frameX1 = Frame(master)
frameX1.pack(side=LEFT, expand=1, anchor=W)
entryX1 = Entry(frameX1,width=10)
entryX1.pack(side=TOP,padx=10,pady=10)
entryX1IP = Entry(frameX1,width=10)
entryX1IP.pack(side=TOP,padx=10,pady=10)
#####################
master.mainloop() # Continue loop till user close tab