Develop Reference

Create Functions for New Windows in Python

I have a function that creates a new window and updates some values to insert into one of the Entry widgets in the new window, as part of a times table quiz. I then need to create a new function that runs when the submit button is clicked and checks that the user's answer is correct. However, this new function gives me a NameError when it runs because it cannot identify that widgets in the new window, only checking the widgets in the original window. How do I get it to check the widgets in the new window?
Original window:
Label(window,text="TIMES TABLES").pack()
game_btn = Button(window, text="Play Game",command=playGameClicked)
game_btn.pack()
Function that creates new window:
def playGameClicked():
#create new window
newWindow = Toplevel(window)
newWindow.geometry("500x300+0+0")
Label(newWindow, text = "Times Tables Game").pack()
Label(newWindow,text="Question:",font=("Helvetica",10),width=10,).pack()
question_box = Entry(newWindow,width=30,background="light blue")
question_box.pack()
Label(newWindow,text="Your Answer:",font=("Helvetica",10),width=10).pack()
answer_box = Entry(newWindow,width=50,background="light green")
answer_box.pack()
submit_btn = Button(newWindow,text="Submit",width=10,command=submitClicked)
submit_btn.pack()
Label(newWindow,text="You are...",font=("Helvetica",10),width=10).pack()
correction_box = Text(newWindow,width=15,height=1,background="light blue")
correction_box.pack()
#new question (all_tables_dict is a long dictionary of 1-12xtables e.g"1*2":2)
question_box.delete(0,END)
keys = list(all_tables_dict.keys())
new_question = random.choice(keys)
question_box.insert(END, new_question)
When the submit button is clicked: (this is the function that doesn't work)
def submitClicked():
answer_box.get(0.0,END)
try:
answer = all_tables_dict[question]
correct=True
except:
correct=False
if correct==True:
correction_box.insert("CORRECT!")
else:
correction_box.insert("INCORRECT!")

You didn't show full error message and I can't run it so I will guess
All variables created inside function are local and they can't be accessed in other functions. You have to inform function that it has to assign widget to global variable.
def playGameClicked():
global answer_box
global correction_box
# ... code ...
answer_box = ...
# ... code ...
correction_box = ...
# ... code ...

Create Tkinter buttons in a loop that reference each other

I'm trying to create a series of tkinter buttons with a loop that are .grid'd to their own respective frames. I want every button to have a function that .tkraises the next frame in the list of frames that I create. Any idea how? Here's what I've got. The buttons/ frames are created I think but the .tkraise function doesn't work. Thanks
from tkinter import *
from PIL import ImageTk, Image
## Define root and geometry
root = Tk()
root.geometry('200x200')
# Define Frames
winlist = list()
winlist = Frame(root, bg='red'), Frame(root, bg='green'), Frame(root, bg='blue')
# Configure Rows
root.grid_rowconfigure(0, weight = 1)
root.grid_columnconfigure(0, weight = 1)
# Place Frames
for window in winlist:
window.grid(row=0, column = 0, sticky = 'news')
# Raises first window 'To the top'
winlist[0].tkraise()
# Function to raise 'window' to the top
def raise_frame(window):
window.tkraise()
d = {}
count = 0
for x in range(0, 3):
d["label{0}".format(x)] = Label(winlist[x], text = "label{0}".format(x))
if count <=1:
try:
d["button{0}".format(x)] = Button(winlist[x], text = "button{0}".format(x), command = raise_frame(winlist[x+1]))
d["button{0}".format(x)].pack(side=TOP)
except:
pass
else:
d["label{0}".format(x)].pack(side=TOP)
count += 1
root.mainloop()

The issue is on the command option of the line:
d["button{0}".format(x)] = Button(winlist[x], text = "button{0}".format(x), command = raise_frame(winlist[x+1]))
It will execute raise_frame(winlist[x+1]) immediately and then assign the result (which is None) to command option. Therefore, clicking the button later does nothing.
You need to use lambda instead:
d["button{0}".format(x)] = Button(winlist[x], text="button{0}".format(x),
command=lambda x=x: raise_frame(winlist[x+1]))

I answered my own question. instead of using frames I went back to creating Tk() objects. I made a loop that runs a function that creates Tk() objects and passed in a variable that carried the count of my loop. I used that count to change information on each Tk() object and instead made the 'command =' of each button include a Tk().destroy function. This creates all the windows I wanted all at once and I can perform an action and exit the window. It's progress. Thanks,
Tim,

how to create new checkbuttons with a mouse click in python

I want to create a program where the user can create different buttons with the click of the mouse, those buttons should be independent. With this logic, the user can create a checkbutton that works, change from green to red when is selected. My problem is that if the user click the mouse again, the checkbutton moves instead of creating a new checkbutton. Any suggestion how to do it?
from tkinter import *
root = Tk()
button1 = IntVar()
def color_checkbutton(): # define the colors of the checkbutton
if button1.get() == 1:
example_checkbutton.configure(bg='red')
else:
example_checkbutton.configure(bg='green')
example_checkbutton = Checkbutton(root, variable=button1, textvariable=button1, command=color_checkbutton)
def place_checkbutton_in_canvas(e): # order to insert the checkbutton
xx_and = e.x
yy_and = e.y
example_checkbutton.place(x=xx_and, y=yy_and)
root.bind('<Button-1>', place_checkbutton_in_canvas)
root.mainloop()

You do only have one example_checkbutton. Whenever you call the .place()method, this button is moved around.
If you want new ones, just create them as new Checkbox-widgets:
def place_checkbutton_in_canvas(e): # order to insert the checkbutton
if len(str(e.widget))<3: ## Don't place a new one if a checkbox was clicked
xx_and = e.x
yy_and = e.y
Checkbutton(root, variable=button1, textvariable=button1, command=color_checkbutton).place(x=xx_and, y=yy_and)
This creates new checkbuttons which are all linked to the button1 variable.
EDIT:
If you want new checkbuttons, you'll have to maintain a list of IntVar() and Checkbutton() objects which is getting longer with each click. The code below should work. I also execute the color change upon creation to create them green and red.
from tkinter import *
root = Tk()
buttons = []
class CMD: #Auxilliary function for callbacks using parameters. Syntax: CMD(function, argument1, argument2, ...)
def __init__(s1, func, *args):
s1.func = func
s1.args = args
def __call__(s1, *args):
args = s1.args+args
s1.func(*args)
def color_checkbutton(pos=0): # define the colors of the checkbutton
if buttons[pos][0].get() == 1:
buttons[pos][2].configure(bg='red')
else:
buttons[pos][2].configure(bg='green')
def place_checkbutton_in_canvas(e): # order to insert the checkbutton
if len(str(e.widget))<3: ## Don't place a new one if a checkbox was clicked
b = IntVar()
pos = len(buttons)
xx_and = e.x
yy_and = e.y
buttons.append([b,pos, Checkbutton(root, variable=b, textvariable=b, command=CMD(color_checkbutton,pos))])
buttons[-1][2].place(x=xx_and, y=yy_and)
color_checkbutton(pos)
root.bind('<Button-1>', place_checkbutton_in_canvas)
root.mainloop()

Tkinter - Update changes in variables in previously generated widgets, from dictionary

I need to represent in "ventana2" the pairs entered in "ventana", so that a new frame appears when the key is new. When the key already exists in the dictionary, I need to change the old value in the frame created for that key previously (the new value is adding old and new).
I can not get the frames permanently related to my dictionary partner, through the key.
Thank you very much in advance, and sorry for my english.
Here is a summary of the code:
import tkinter as tk
ventana = tk.Tk()
ventana2 = tk.Tk()
name = tk.StringVar()
tk.Entry(ventana, textvariable=name, width=30).grid(row=0, column=1)
tk.Label(ventana, text = 'Nombre').grid(row=0, column=0)
value = tk.StringVar()
tk.Entry(ventana, textvariable=value, width=30).grid(row=1, column=1)
tk.Label(ventana, text = 'Celular').grid(row=1, column=0)
contactos={}
def intro():
nom = name.get()
if nom in contactos:
cel = contactos[nom] + float(value.get())
contactos[nom] = cel
else:
cel = float(value.get())
contactos[nom] = cel
create_widget()
def create_widget():
frame = tk.Frame(ventana2)
frame.pack()
nomb = tk.Label(frame, text=name.get()).pack(side=tk.LEFT)
telf = tk.Label(frame, text=contactos[name.get()]).pack(side=tk.RIGHT)
intro_btn = tk.Button(ventana, text='Intro', command = intro)
intro_btn.grid(row=2, column=0, columnspan=2, sticky = 'ew')
ventana.mainloop()

Labels created inside the create_widget() function is in the function scope. After the function ends all references to the label is lost. So you need to think of a way to save references to the label (suggest return statement) and associate them to the dictionary of contactos.
Update - relate a frame with a value
Save a reference to the object you wish to remember and the name you want to use to recall it in a list(or dict or tuple et.). Then append all that to your global list of widgets. For example:
nomb = tk.Label( ... )
widget_parameters = ['Nomb Label', nomb]
global_widget_list.append(widget_parameters)
Then you can search the global_widget_list for any widget you have named and get a referance to that widget.
I have included some example code to illustrate one way that you can accomplish that. Play around with it until you understand it and you will be able to implement it in your own application.
from tkinter import *
import time
root = Tk()
root.geometry('300x200')
global_widget_list = [] # List for holding all widgets
def make_label(): # Create label
text_label = Label(root,text='Text input')
text_label.pack()
global_widget_list.append(['Text Label',text_label]) # Add widget to list
def make_input(): # Create entry
inputvar = StringVar()
text_input = Entry(root,width=20,textvariable=inputvar)
text_input.pack()
global_widget_list.append(['Text Input',text_input,inputvar]) # Add widget to list
make_label() # Run functions to cretae GUI
make_input()
root.update() # Take care of updating GUI
time.sleep(3) # Wait so you have time to see the original, then change it
# Now, loop through all widgets and do what you want
for widget in global_widget_list:
widget_name = widget[0]
widget_id = widget[1]
print(widget_name, 'has identity', widget_id)
if widget_name == 'Text Label':
print('Changing test label text to: ALL CAPS')
widget_id.configure(text='ALL CAPS')
if widget_name == 'Text Input':
print('Changing text in entry to: SAMPLE')
var = widget[2]
var.set('SAMPLE')
root.update() # Take care of updating GUI
time.sleep(3) # Wait so you have time to see the changes, then change it
print('Removing Entry from application GUI')
global_widget_list[1][1].pack_forget() # Remove entry form GUI

Simple gui that display a repeated set of images when a button is pushed

I made a very simple gui that has a button and shows an image(.gif). My goal is to output another .gif whenever you press the button. There are 2 .gif files in my file directory and the point is to keep switching between these two whenever you press the button.
#Using python2.7.2
import Tkinter
root = Tkinter.Tk()
try:
n
except:
n = 0
def showphoto(par):
if par%2 == 0:
try:
label2.destroy()
except:
pass
photo = Tkinter.PhotoImage(file="masc.gif")
label2 = Tkinter.Label(image=photo)
label2.image = photo
label2.pack()
else:
try:
label2.destroy()
except:
pass
photo = Tkinter.PhotoImage(file="123.gif")
label2 = Tkinter.Label(image=photo)
label2.image = photo
label2.pack()
myContainer1 = Tkinter.Frame(root, width = 100, height = 100)
myContainer1.pack()
def callback(event):
global n
showphoto(n)
n = n + 1
button1 = Tkinter.Button(myContainer1)
button1["text"]= "Next pic"
button1["background"] = "green"
button1.bind("<Button-1>", callback(n))
button1.pack()
root.mainloop()
The current code just outputs the first image (masc.gif) but when I press the button it doesn't switch to the other image(123.gif). What am I doing wrong?

This can achieved much easier with classes as the class holds all the data necessary without the use of global variables.
import Tkinter as tk
from collections import OrderedDict
class app(tk.Frame):
def __init__(self,master=None, **kwargs):
self.gifdict=OrderedDict()
for gif in ('masc.gif','123.gif'):
self.gifdict[gif]=tk.PhotoImage(file=gif)
tk.Frame.__init__(self,master,**kwargs)
self.label=tk.Label(self)
self.label.pack()
self.button=tk.Button(self,text="switch",command=self.switch)
self.button.pack()
self.switch()
def switch(self):
#Get first image in dict and add it to the end
img,photo=self.gifdict.popitem(last=False)
self.gifdict[img]=photo
#display the image we popped off the start of the dict.
self.label.config(image=photo)
if __name__ == "__main__":
A=tk.Tk()
B=app(master=A,width=100,height=100)
B.pack()
A.mainloop()
Of course, this could be done more generally ... (the list of images to cycle through could be passed in for example), and this will switch through all the images in self.gifs ...
This approach also removes the necessity to destroy and recreate a label each time, instead we just reuse the label we already have.
EDIT
Now I use an OrderedDict to store the files. (keys=filename,values=PhotoImages). Then we pop the first element out of the dictionary to plot. Of course, if you're using python2.6 or earlier, you can just keep a list in addition to the dictionary and use the list to get the keys.

button1 = Tkinter.Button(myContainer1)
button1["text"]= "Next pic"
button1["background"] = "green"
button1.bind("<Button-1>", callback(n))
First, you bind the <Button-1> event to None (that's what callback(n) evaluates to). You should bind it to callback (no parentheses a.k.a the call operator).
Second, I suggest you change callback to not accept any arguments, remove the bind call and create your button as:
button1 = Tkinter.Button(myContainer1, command=callback)