Are "self" and "root" different when creating buttons in a Python Class? - python

In the script below button_01 and button_02 are created in "self" and "root" respectively. Is there any functional difference where they are created? The GUI looks the same either way.
import Tkinter as tk
class App(tk.Frame):
def __init__(self, *args, **kwargs):
tk.Frame.__init__(self, *args, **kwargs)
frame1 = tk.Frame(root, padx=2, pady=2, borderwidth=2, relief="raised")
frame1.pack(side=tk.RIGHT)
button_01 = tk.Button(self, text ="tk Button 1") # self with tk.Button
button_01.config(width=15, fg="black", bg="lightskyblue")
button_01.pack(side=tk.BOTTOM)
button_02 = tk.Button(root, text ="tk Button 2") # root with tk.Button
button_02.config(width=15, fg="black", bg="lime")
button_02.pack(side=tk.BOTTOM)
button_03 = tk.Button(frame1, text ="tk Button 3") # frame1 with tk.Button
button_03.config(width=15, fg="black", bg="lightcoral")
button_03.pack(side=tk.TOP)
if __name__ == "__main__":
root = tk.Tk()
app = App(root)
app.pack(fill="both", expand=True)
#
root.mainloop()

No, self and root are not the same. Widgets live in a tree-like hierarchy, with a single root. When you call tk.Tk() you are creating this root window.
self represents the object to which the methods belong. In this case the widget is a subclass of tk.Frame which is a child of root.
Try giving the frame a background color (eg: self.configure(background="red") and you will see that the buttons have different parents. The gui looks the same in this specific example whether you use root or self only because it is an extremely simple gui with a very simple layout.

Related

How do I prevent prevent multiple instances of the same window opening?

I'm currently using tkinter to create a GUI for my program. If I open the golf quiz window and open the help window, then close the golf quiz window and re-open it, I am able to click the help window button and open another instance of the help button. How do I set the Help button to be disabled while the Help window is open?
from tkinter import *
from functools import partial
class Welcome_Screen:
def __init__(self, parent):
self.welcome_screen_frame = Frame(width=200, height=200, pady=10)
self.welcome_screen_frame.grid()
self.quiz_welcome_screen_label = Label(self.welcome_screen_frame, text = "quiz game", font="Arial 20 bold", padx=10)
self.quiz_welcome_screen_label.grid(row=0)
self.welcome_screen_buttons_frame = Frame(self.welcome_screen_frame)
self.welcome_screen_buttons_frame.grid(row=2)
self.golf_quiz_welcome_screen_button = Button(self.welcome_screen_buttons_frame, text="Golf Quiz", font="Arial 10 bold", command=self.golf_quiz_game, padx=10, pady=10)
self.golf_quiz_welcome_screen_button.grid(row=2, column=0, padx=5)
def golf_quiz_game(self):
get_golf_quiz_game = golf_quiz_game(self)
class golf_quiz_game:
def __init__(self, partner):
partner.golf_quiz_welcome_screen_button.config(DISABLED)
self.golf_quiz_box = Toplevel()
self.golf_quiz_box.protocol('WM_DELETE_WINDOW', partial(self.close_golf_quiz_game, partner))
self.golf_quiz_frame = Frame(self.golf_quiz_box)
self.golf_quiz_frame.grid()
self.golf_quiz_heading = Label(self.golf_quiz_frame, text="Golf Quiz game",
font="arial 18 bold", padx=10, pady=10)
self.golf_quiz_heading.grid(row=0)
self.golf_quiz_history_help_dismiss_buttons_frame = Frame(self.golf_quiz_frame)
self.golf_quiz_history_help_dismiss_buttons_frame.grid(row=6, pady=10)
self.help_button = Button(self.golf_quiz_history_help_dismiss_buttons_frame, text="Help", font="Arial 10 bold",command=self.Help, padx=10, pady=10)
self.help_button.grid(row=6, column=1, padx=5)
def close_golf_quiz_game(self, partner):
partner.golf_quiz_welcome_screen_button.config(state=NORMAL)
self.golf_quiz_box.destroy()
def Help(self):
get_help = Help(self)
class Help:
def __init__(self, partner):
partner.help_button.config(state=DISABLED)
self.help_box = Toplevel()
self.help_box.protocol('WM_DELETE_WINDOW', partial(self.close_Help, partner))
self.help_frame = Frame(self.help_box)
self.help_frame.grid()
self.help_heading = Label(self.help_frame, text="Help", font="arial 18 bold")
self.help_heading.grid(row=0)
self.help_text = Label(self.help_frame, text="Test",
width=60, wrap=400)
self.help_text.grid(row=1)
self.help_button = Button(self.help_frame, text="Dismiss", width=10, font="Arial 10 bold", command=partial(self.close_Help, partner), padx=10, pady=10)
self.help_button.grid(row=2, pady=10)
def close_Help(self, partner):
if partner.help_button.winfo_exists():
partner.help_button.config(state=NORMAL)
self.help_box.destroy()
# main routine
if __name__ == "__main__":
root = Tk()
root.title("quiz game")
something = Welcome_Screen(root)
root.mainloop()
Here is how you can do that (this is also the size (linewise (approx.)) of the minimal reproducible example which you should have provided):
from tkinter import Tk, Toplevel, Button
def close_top(top):
btn.config(state='normal')
top.destroy()
def open_help():
btn.config(state='disabled')
top = Toplevel(root)
top.protocol('WM_DELETE_WINDOW', lambda: close_top(top))
top.focus_force()
# put the rest of help stuff here
root = Tk()
btn = Button(root, text='Help', command=open_help)
btn.pack()
root.mainloop()
Class based approach:
from tkinter import Tk, Toplevel, Button
# this would be the window from where you open the help window
class MainWindow(Tk):
def __init__(self):
Tk.__init__(self)
self.btn = Button(self, text='Help',
command=lambda: self.open_help(self.btn))
self.btn.pack()
def open_help(self, btn):
HelpWindow(self, btn)
# this would be the help window
class HelpWindow(Toplevel):
def __init__(self, master, button):
Toplevel.__init__(self, master)
self.button = button
self.button.config(state='disabled')
self.focus_force()
self.protocol('WM_DELETE_WINDOW', self.close)
def close(self):
self.button.config(state='normal')
self.destroy()
MainWindow().mainloop()
Few things:
First of you can simply inherit from container and window classes that way you don't have to separately create them in the class and you can easily reference them in the class using just self
.focus_force() does what it says, it forces focus on the widget
Important (suggestions)
I strongly advise against using wildcard (*) when importing something, You should either import what You need, e.g. from module import Class1, func_1, var_2 and so on or import the whole module: import module then You can also use an alias: import module as md or sth like that, the point is that don't import everything unless You actually know what You are doing; name clashes are the issue.
I strongly suggest following PEP 8 - Style Guide for Python Code. Function and variable names should be in snake_case, class names in CapitalCase. Don't have space around = if it is used as a part of keyword argument (func(arg='value')) but use if it is used for assigning a value (variable = 'some value'). Have two blank lines around function and class declarations.
You need to make use of class variables inside golf_quiz_game in order to have only one instance of Help window:
class golf_quiz_game:
# class variables
_help_button = None # reference to instance "Help" button
_help_win = None # reference to instance "Help" window
def __init__(self, partner):
...
# set button state based on whether "Help" window is open or not
self.help_button.config(state="normal" if self.__class__._help_win is None else "disabled")
# update class reference of "Help" button
self.__class__._help_button = self.help_button
def close_golf_quiz_game(self, partner):
partner.golf_quiz_welcome_screen_button.config(state=NORMAL)
self.golf_quiz_box.destroy()
# update class reference of "Help" button
self.__class__._help_button = None
def Help(self):
if self.__class__._help_win is None:
# no "Help" window is open, create one
self.__class__._help_win = Help(self)
def help_closed(self):
if self.__class__._help_button:
# enable the "Help" button
self.__class__._help_button.config(state="normal")
# update "Help" window status
self.__class__._help_win = None
class Help:
...
def close_Help(self, partner):
self.help_box.destroy()
# notify partner that "Help" window is closed
partner.help_closed()

Is there a way to display a class in python tkinter as a Frame, so other things can be added?

I want to have a tkinter window that displays both a cronometer and a sudoku. The cronometer is a class, so how can I add it to the window that displays the sudoku?
I already managed to get two separate windows, but I couldn't make one with both things.
def GUI4x4(dif): #This function gets just called from other place
# What I want is to be able to display this class
# Cronometer in the main window that's created below
class Cronometer():
...
def __init__(self):
self.crono=Tk()
self.tiempo = StringVar()
self.tiempo.set("00:00:00")
self.label = Label(self.crono,textvariable=self.tiempo, bg="white")
self.label.grid(column=0,row=0)
self.label.configure(font=("Times 13 bold"))
self.btnI = Button(self.crono, bg="white", text="Start",command=self.iniciarT,font=("Times 11"))
self.btnI.grid(pady=3,column=0,row=1)
self.btnP = Button(self.crono, bg="white", text="Pause",command=self.pausarT,font=("Times 11"))
self.btnP.grid(pady=3,column=0,row=2)
self.btnR = Button(self.crono, bg="white", text="Restart",command=self.reiniciarT,font=("Times 11"))
self.btnR.grid(pady=3,column=0,row=3)
GUI = Tk() # This creates the main window, and places
# 34 buttons in it
...
# Defining the Buttons
btn00 = Button(GUI, text=Tablero[0][0], width=5, height=3, activebackground="lime")
btn01 = Button(GUI, text=Tablero[0][1], width=5, height=3, activebackground="lime")
btn02 = Button(GUI, text=Tablero[0][2], width=5, height=3, activebackground="lime")
...
btn33 = Button(GUI, text=Tablero[3][3], width=5, height=3, activebackground="lime")
#Placing the 34 buttons
btn00.grid(row=0, column=0)
btn01.grid(row=0, column=1)
btn02.grid(row=0, column=2)
...
btn33.grid(row=3, column=3)
The standard way to deal with this with tkinter is that each "widget" in the application is its own class based on the tkinter Frame widget, one class for the chrono, another for the sudoko game. There might even be a main app class.
Advantage of this method is that each widget frame can be created independently and then joined together later. These classes might also be split up in to separate code files.
A fairly simple example below
import tkinter as tk
class Chromometer(tk.Frame):
def __init__(self,master=None,**kw):
tk.Frame.__init__(self,master=master,**kw)
self.tiempo = tk.StringVar()
self.tiempo.set("00:00:00")
self.label = tk.Label(self,textvariable=self.tiempo, bg="white")
self.label.grid(column=0,row=0)
class Sudoko(tk.Frame):
def __init__(self,master=None,**kw):
tk.Frame.__init__(self,master=master,**kw)
self.label = tk.Label(self,text="Sudoko", bg="white")
self.label.grid(column=0,row=0)
class MainApp(tk.Frame):
def __init__(self,master=None,**kw):
tk.Frame.__init__(self,master=master,**kw)
self.chrono = Chromometer(master=self)
self.chrono.grid()
self.sudoko = Sudoko(master=self)
self.sudoko.grid()
if __name__ == '__main__':
root = tk.Tk()
app = MainApp(master=root)
app.grid()
root.mainloop()
Each class will have their own methods to perform the functionality needed by each. The chromo/chrono class will have a method to update the timer.

Checking if Tkinter Widget (OptionMenu) is disabled

I feel like I've scoured the web for an eternity, rephrased my question a thousand times for something I feel like should be very simple.
I wonder if there is a way to check if a Tkinter Widget is active (not greyed out / disabled). I have a set of OptionMenus that start out disabled, and are configured to state=ACTIVE when they click a checkbox, so that the user can select which OptionMenus they want to use.
When I try to "submit" the fields in the OptionMenus, I only want the ones that are ACTIVE. I already tried if OptionMenu.state == ACTIVE but then I get an error that OptionMenu has no attribute state, even though I configure that earlier.
Here is a sample of my code:
from tkinter import *
class Application(Frame):
# Initializing the window and the required variables
def __init__(self, master=None):
Frame.__init__(self, master)
self.checkbox_in_use = BooleanVar(self, False)
self.checkbox = Checkbutton(self, text="check",
var=self.checkbox_in_use,
command=self.check_change
self.checkbox.grid(row=0, column=1, sticky='W')
self.menu = OptionMenu(title_setting,
"Menu",
"Menu",
["Menu1", "Menu2"])
self.menu.grid(row=1, column=1)
self.menu.config(state=DISABLED)
submit = Button(self, text="submit",
command=self.submit_function)
submit.grid(row=2, column=0)
self.master = master
self.init_window()
# Initialize the window
def init_window(self):
self.master.title("Example")
self.pack(fill=BOTH, expand=1)
def check_change(self):
if self.checkbox_in_use.get():
self.menu.config(state=ACTIVE)
else:
self.menu.config(state=DISABLED)
def submit_function(self):
# This is the part I want to do something with.
if self.menu.state == ACTIVE:
print("You are good to go! Do the stuff.")
root = Tk()
root.geometry("400x300")
app = Application(root)
root.mainloop()
Thank you for all responses.
All you need is cget() for this. self.menu.cget('state') will do the trick.
That said I want to point out some other things in your code.
You Application class already has an __init__ at the start so why use:
# Initialize the window
def init_window(self):
self.master.title("Example")
self.pack(fill=BOTH, expand=1)
You really should not pack the frame from inside the frame class but rather when calling the class. Also pack wont work here it will throw an error. Do this instead: app = Application(root).grid().
Take a look at the reformatted example below (with cget()).
from tkinter import *
class Application(Frame):
def __init__(self, master=None):
Frame.__init__(self, master)
self.master.title("Example")
self.checkbox_in_use = BooleanVar(self, False)
self.checkbox = Checkbutton(self, text="check", var=self.checkbox_in_use, command=self.check_change)
self.checkbox.grid(row=0, column=1, sticky='W')
self.menu = OptionMenu(master,"Menu","Menu",["Menu1", "Menu2"])
self.menu.grid(row=1, column=1)
self.menu.config(state=DISABLED)
Button(self, text="submit", command=self.submit_function).grid(row=2, column=0)
def check_change(self):
if self.checkbox_in_use.get():
self.menu.config(state=ACTIVE)
else:
self.menu.config(state=DISABLED)
def submit_function(self):
print(self.menu.cget('state'))
root = Tk()
root.geometry("400x300")
app = Application(root).grid()
root.mainloop()

Python Tkinter widgets added to root window instead of Toplevel window [duplicate]

This question already has an answer here:
Python - Tkinter - Widgets created inside a class inherited from Toplevel() appear in a different frame OUTSIDE the class, Toplevel() class is empty
(1 answer)
Closed 5 years ago.
Using Python 2.7 here. I am trying to add a basic settings window, but when I open a Toplevel window and try to add widgets to it, the widgets get added to the main window instead. Here is an example:
import Tkinter as tk
class MainWindow (tk.Frame):
def __init__ (self, root):
tk.Frame.__init__(self, root)
self.root = root
self.root.geometry("300x200")
button = tk.Button(self, text="Settings", command=self.open_settings).pack()
def open_settings (self):
settings_win = tk.Toplevel(self.root, height=300, width=400)
settings_win.focus_set()
top_frame = tk.Frame(settings_win, bg="red").pack(side="top", fill="both", expand=True)
bottom_frame = tk.Frame(settings_win, bg="blue").pack(side="bottom", fill="both", expand=True)
top_label = tk.Label(top_frame, text="Top Label").pack()
bottom_label = tk.Label(bottom_frame, text="Bottom Label").pack()
if __name__ == '__main__':
root = tk.Tk()
MainWindow(root).pack(fill="both", expand=True)
root.mainloop()
Here is what I see when I click on the Settings button below. The second window opens but the labels show up on the main window.
its because your packing on the same line, check out the answer to this question, he explains it in detail: Python - Tkinter - Widgets created inside a class inherited from Toplevel() appear in a different frame OUTSIDE the class, Toplevel() class is empty
this should fix it:
top_frame = tk.Frame(settings_win, bg="red")
top_frame.pack(side="top", fill="both", expand=True)
bottom_frame = tk.Frame(settings_win, bg="blue")
bottom_frame.pack(side="bottom", fill="both", expand=True)
top_label = tk.Label(top_frame, text="Top Label")
top_label.pack()
bottom_label = tk.Label(bottom_frame, text="Bottom Label")
bottom_label.pack()
here is a screenshot:

Force set tkinter window to always have focus

Is there a way to tell Tkinter that I want some widget to always remain focused? I've created a minimal example that can be run to show my issue , here's an example window with small toplevel windows also overlayed:
Now if I click the upper title tk, the main window comes into focus and suddenly the small windows are behind the main window
I want to treat these smaller windows as if they are always in focus until the user specifically closes them. Of course this is a minimal example that is an idea behind a small subsection of my large application , is there any easy setting I can use for the toplevel that guarantees it will always remain in focus regardless of other windows? Here's the actual code that can be run to replicate this:
from Tkinter import *
class PropertyDialog(Toplevel):
def __init__(self, root, string):
Toplevel.__init__(self)
self.wm_overrideredirect(1)
self.root = root
self.\
geometry('+%d+%d' %
(root.winfo_pointerx(),
root.winfo_pointery()))
try:
self.tk.call('::Tk::unsupported::MacWindowStyle',
'style', self._w,
'help', 'noActivates')
except TclError:
pass
window_frame = Frame(self)
window_frame.pack(side=TOP, fill=BOTH, expand=True)
exit_frame = Frame(window_frame, background='#ffffe0')
exit_frame.pack(side=TOP, fill=X, expand=True)
button = Button(exit_frame, text='x', width=3, command=self.free,
background='#ffffe0', highlightthickness=0, relief=FLAT)
button.pack(side=RIGHT)
text_frame = Frame(window_frame)
text_frame.pack(side=TOP, fill=BOTH, expand=True)
label = Label(text_frame, text=string, justify=LEFT,
background='#ffffe0',
font=('tahoma', '8', 'normal'))
label.pack(ipadx=1)
def free(self):
self.destroy() # first we destroy this one
for val,widget in enumerate(dialogs): # go through the dialogs list
if widget is self: # when we find this widget
dialogs.pop(val) # pop it out
break # and stop searching
if dialogs: # if there are any dialogs left:
for widget in dialogs: # go through each widget
widget.lift(aboveThis=self.root) # and lift it above the root
def bind():
"""
toggle property window creation mode
"""
root.bind('<ButtonPress-1>', create)
def create(event):
"""
Create actual window upon mouse click
"""
dialogs.append(PropertyDialog(root, 'help me'))
root = Tk()
dialogs = []
root.geometry('%dx%d' % (300,400))
Button(root, text='create', command=bind).pack()
root.mainloop()
change this:
if dialogs: # if there are any dialogs left:
for widget in dialogs: # go through each widget
widget.lift(aboveThis=self.root) # and lift it above the root
to this:
if dialogs: # if there are any dialogs left:
for widget in dialogs: # go through each widget
widget.lift() # and lift it above the root
the widgets will stay above the main window.
EDIT:
Sorry that only half worked... the widows will stay above sometimes with that code
:-X
It was keeping the widgets on top until you closed one of them.... this code does keep the widgets on top
it uses the self.attributes("-topmost", True) when you spawn the windows.
Sorry again.
from Tkinter import *
class PropertyDialog(Toplevel):
def __init__(self, root, string):
Toplevel.__init__(self)
self.wm_overrideredirect(1)
self.root = root
self.\
geometry('+%d+%d' %
(root.winfo_pointerx(),
root.winfo_pointery()))
try:
self.tk.call('::Tk::unsupported::MacWindowStyle',
'style', self._w,
'help', 'noActivates')
except TclError:
pass
window_frame = Frame(self)
window_frame.pack(side=TOP, fill=BOTH, expand=True)
exit_frame = Frame(window_frame, background='#ffffe0')
exit_frame.pack(side=TOP, fill=X, expand=True)
button = Button(exit_frame, text='x', width=3, command=self.free,
background='#ffffe0', highlightthickness=0, relief=FLAT)
button.pack(side=RIGHT)
text_frame = Frame(window_frame)
text_frame.pack(side=TOP, fill=BOTH, expand=True)
label = Label(text_frame, text=string, justify=LEFT,
background='#ffffe0',
font=('tahoma', '8', 'normal'))
label.pack(ipadx=1)
self.attributes("-topmost", True)
def free(self):
self.destroy() # first we destroy this one
def bind():
"""
toggle property window creation mode
"""
root.bind('<ButtonPress-1>', create)
def create(event):
"""
Create actual window upon mouse click
"""
dialogs.append(PropertyDialog(root, 'help me'))
root = Tk()
dialogs = []
root.geometry('%dx%d' % (300,400))
Button(root, text='create', command=bind).pack()
root.mainloop()
I recommend moving away from Toplevel widgets, since those are separate windows and you're suppressing their window-like behavior. This version makes PropertyDialog inherit from Frame instead of Toplevel, using the place() geometry manager. When you click the main window, it first checks whether the widget clicked was the main window or a popup window to prevent a new popup from appearing when you close an existing one. Changed areas are marked with #CHANGED#.
from Tkinter import *
class PropertyDialog(Frame): #CHANGED#
def __init__(self, root, string, event): #CHANGED#
Frame.__init__(self) #CHANGED#
self.root = root
try:
self.tk.call('::Tk::unsupported::MacWindowStyle',
'style', self._w,
'help', 'noActivates')
except TclError:
pass
exit_frame = Frame(self, background='#ffffe0') #CHANGED#
exit_frame.pack(side=TOP, fill=X, expand=True)
button = Button(exit_frame, text='x', width=3, command=self.free,
background='#ffffe0', highlightthickness=0, relief=FLAT)
button.pack(side=RIGHT)
text_frame = Frame(self) #CHANGED#
text_frame.pack(side=TOP, fill=BOTH, expand=True)
label = Label(text_frame, text=string, justify=LEFT,
background='#ffffe0',
font=('tahoma', '8', 'normal'))
label.pack(ipadx=1)
self.place(x=event.x, y=event.y, anchor=NW) #CHANGED#
def free(self):
self.destroy()
# other things you want to do - if there's nothing else,
# just bind the close button to self.destroy
def bind():
"""
toggle property window creation mode
"""
root.bind('<ButtonPress-1>', create)
def create(event):
"""
Create actual window upon mouse click
"""
if event.widget is root: #CHANGED#
dialogs.append(PropertyDialog(root, 'help me', event))
root = Tk()
dialogs = []
root.geometry('%dx%d' % (300,400))
Button(root, text='create', command=bind).pack()
root.mainloop()

Categories