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()
The technical post webpages of this site follow the CC BY-SA 4.0 protocol. If you need to reprint, please indicate the site URL or the original address.Any question please contact:yoyou2525@163.com.