This is a shortened example of a longer application where I have multiple pages of widgets collecting information input by the user. The MyApp instantiates each page as a class. In the example, PageTwo would like to print the value of the StringVar which stores the data from an Entry widget in PageOne.
How do I do that? Every attempt I've tried ends up with one exception or another.
from tkinter import *
from tkinter import ttk
class MyApp(Tk):
def __init__(self):
Tk.__init__(self)
container = ttk.Frame(self)
container.pack(side="top", fill="both", expand = True)
self.frames = {}
for F in (PageOne, PageTwo):
frame = F(container, self)
self.frames[F] = frame
frame.grid(row=0, column=0, sticky = NSEW)
self.show_frame(PageOne)
def show_frame(self, cont):
frame = self.frames[cont]
frame.tkraise()
class PageOne(ttk.Frame):
def __init__(self, parent, controller):
ttk.Frame.__init__(self, parent)
ttk.Label(self, text='PageOne').grid(padx=(20,20), pady=(20,20))
self.make_widget(controller)
def make_widget(self, controller):
self.some_input = StringVar
self.some_entry = ttk.Entry(self, textvariable=self.some_input, width=8)
self.some_entry.grid()
button1 = ttk.Button(self, text='Next Page',
command=lambda: controller.show_frame(PageTwo))
button1.grid()
class PageTwo(ttk.Frame):
def __init__(self, parent, controller):
ttk.Frame.__init__(self, parent)
ttk.Label(self, text='PageTwo').grid(padx=(20,20), pady=(20,20))
button1 = ttk.Button(self, text='Previous Page',
command=lambda: controller.show_frame(PageOne))
button1.grid()
button2 = ttk.Button(self, text='press to print', command=self.print_it)
button2.grid()
def print_it(self):
print ('The value stored in StartPage some_entry = ')#What do I put here
#to print the value of some_input from PageOne
app = MyApp()
app.title('Multi-Page Test App')
app.mainloop()
Leveraging your controller
Given that you already have the concept of a controller in place (even though you aren't using it), you can use it to communicate between pages. The first step is to save a reference to the controller in each page:
class PageOne(ttk.Frame):
def __init__(self, parent, controller):
self.controller = controller
...
class PageTwo(ttk.Frame):
def __init__(self, parent, controller):
self.controller = controller
...
Next, add a method to the controller which will return a page when given the class name or some other identifying attribute. In your case, since your pages don't have any internal name, you can just use the class name:
class MyApp(Tk):
...
def get_page(self, classname):
'''Returns an instance of a page given it's class name as a string'''
for page in self.frames.values():
if str(page.__class__.__name__) == classname:
return page
return None
note: the above implementation is based on the code in the question. The code in the question has it's origin in another answer here on stackoverflow. This code differs from the original code slightly in how it manages the pages in the controller. This uses the class reference as a key, the original answer uses the class name.
With that in place, any page can get a reference to any other page by calling that function. Then, with a reference to the page, you can access the public members of that page:
class PageTwo(ttk.Frame):
...
def print_it(self):
page_one = self.controller.get_page("PageOne")
value = page_one.some_entry.get()
print ('The value stored in StartPage some_entry = %s' % value)
Storing data in the controller
Directly accessing one page from another is not the only solution. The downside is that your pages are tightly coupled. It would be hard to make a change in one page without having to also make a corresponding change in one or more other classes.
If your pages all are designed to work together to define a single set of data, it might be wise to have that data stored in the controller, so that any given page does not need to know the internal design of the other pages. The pages are free to implement the widgets however they want, without worrying about which other pages might access those widgets.
You could, for example, have a dictionary (or database) in the controller, and each page is responsible for updating that dictionary with it's subset of data. Then, at any time you can just ask the controller for the data. In effect, the page is signing a contract, promising to keep it's subset of the global data up to date with what is in the GUI. As long as you maintain the contract, you can do whatever you want in the implementation of the page.
To do that, the controller would create the data structure before creating the pages. Since we're using tkinter, that data structure could be made up of instances of StringVar or any of the other *Var classes. It doesn't have to be, but it's convenient and easy in this simple example:
class MyApp(Tk):
def __init__(self):
...
self.app_data = {"name": StringVar(),
"address": StringVar(),
...
}
Next, you modify each page to reference the controller when creating the widgets:
class PageOne(ttk.Frame):
def __init__(self, parent, controller):
self.controller=controller
...
self.some_entry = ttk.Entry(self,
textvariable=self.controller.app_data["name"], ...)
Finally, you then access the data from the controller rather than from the page. You can throw away get_page, and print the value like this:
def print_it(self):
value = self.controller.app_data["address"].get()
...
I faced a challenge in knowing where to place the print_it function.
i added the following to make it work though I don't really understand why they are used.
def show_frame(self,page_name):
...
frame.update()
frame.event_generate("<<show_frame>>")
and added the show_frame.bind
class PageTwo(tk.Frame):
def __init__(....):
....
self.bind("<<show_frame>>", self.print_it)
...
def print_it(self,event):
...
Without the above additions, when the mainloop is executed,
Page_Two[frame[print_it()]]
the print_it function executes before PageTwo is made Visible.
try:
import tkinter as tk # python3
from tkinter import font as tkfont
except ImportError:
import Tkinter as tk #python2
import tkFont as tkfont
class SampleApp(tk.Tk):
def __init__(self, *args, **kwargs):
tk.Tk.__init__(self, *args, **kwargs)
self.title_font = tkfont.Font(family="Helvetica", size=18, weight="bold", slant="italic")
# data Dictionary
self.app_data = {"name": tk.StringVar(),
"address": tk.StringVar()}
# the container is where we'll stack a bunch of frames
# on top of each other, then the one we want visible
# will be raised above the others.
container = tk.Frame(self)
container.pack(side="top", fill="both", expand=True)
container.grid_rowconfigure(0, weight=1)
container.grid_columnconfigure(0,weight=1)
self.frames = {}
for F in (StartPage, PageOne, PageTwo):
page_name = F.__name__
frame = F(parent=container, controller=self)
self.frames[page_name] = frame
# put all of the pages in the same location;
# the one on the top of the stacking order
# will be the one that is visible
frame.grid(row=0, column=0, sticky="nsew")
self.show_frame("StartPage")
def show_frame(self, page_name):
''' Show a frame for the given page name '''
frame = self.frames[page_name]
frame.tkraise()
frame.update()
frame.event_generate("<<show_frame>>")
class StartPage(tk.Frame):
def __init__(self, parent, controller):
tk.Frame.__init__(self, parent)
self.controller = controller
label = tk.Label(self, text="this is the start page", font=self.controller.title_font)
label.pack(side="top", fill="x", pady=10)
# Update the Name value only
self.entry1 = tk.Entry(self,text="Entry", textvariable=self.controller.app_data["name"])
self.entry1.pack()
button1 = tk.Button(self, text="go to page one", command = lambda: self.controller.show_frame("PageOne")).pack()
button2 = tk.Button(self, text="Go to page Two", command = lambda: self.controller.show_frame("PageTwo")).pack()
class PageOne(tk.Frame):
def __init__(self, parent, controller):
tk.Frame.__init__(self, parent)
self.controller = controller
label = tk.Label(self, text="This is page 1", font=self.controller.title_font)
label.pack(side="top", fill="x", pady=10)
# Update the Address value only
self.entry1 = tk.Entry(self,text="Entry", textvariable=self.controller.app_data["address"])
self.entry1.pack()
button = tk.Button(self, text="Go to the start page", command=lambda: self.controller.show_frame("StartPage"))
button.pack()
class PageTwo(tk.Frame):
def __init__(self, parent, controller):
tk.Frame.__init__(self, parent)
self.controller = controller
# Bind the print_it() function to this Frame so that when the Frame becomes visible print_it() is called.
self.bind("<<show_frame>>", self.print_it)
label = tk.Label(self, text="This is page 2", font=self.controller.title_font)
label.pack(side="top", fill="x", pady=10)
button = tk.Button(self, text="Go to the start page",
command=lambda: self.controller.show_frame("StartPage"))
button.pack()
def print_it(self,event):
StartPage_value = self.controller.app_data["name"].get()
print(f"The value set from StartPage is {StartPage_value}")
PageOne_value= self.controller.app_data["address"].get()
print(f"The value set from StartPage is {PageOne_value}")
if __name__ == "__main__":
app = SampleApp()
app.mainloop()
Related
This is the window provides the container and methods which allow frame swapping:
class Login_Window(ctk.CTk):
def __init__(self, *args, **kwargs):
super().__init__()
self.geometry('400x400')
self.title('Music Mayhem')
self.resizable(False, False)
container = ctk.CTkFrame(master=self)
container.pack(side='top', fill='both', expand=True)
container.grid_rowconfigure(0, weight=1)
container.grid_columnconfigure(0, weight=1)
self.frames={}
for F in (LoginFrame, RegEmailFrame):
frame = F(container, self)
self.frames[F] = frame
frame.grid(row=0, column=0, sticky= 'nsew')
frame.grid_columnconfigure(0,weight=1)
frame.grid_rowconfigure(0,weight=1)
self.show_frame(LoginFrame)
def show_frame(self, cont):
frame = self.frames[cont]
frame.tkraise()
In order to swap the frames, a button has to be created in the frame that is going to be swapped. How would i go about creating an instance of another class within these frames which will also call the show_frame method? Here is the code for the frames- this could be ran as long as you have tkinter and custom tkinter installed. The only aspect that should supposedly not work are the buttons in the menu frame.
Yes, in this situation the menu frame is not needed but this is just a simple example because the actual code is way too long to be included here.
I have tried adding the menu frame into the list of frames to be swapped (in the class above) and giving it the same parent and controller attributes as the other frame but that required a parent and controller argument to be passed through when it is called in the Login and Register frames.
Is there a way to get round this or a simpler method that could be implemented instead?
class LoginFrame (tk.Frame):
def __init__(self,parent, controller):
tk.Frame.__init__(self, parent)
self.menu = Menu(self)
self.menu.grid(row=0, column=0)
self.loginBtn = ctk.CTkButton(master=self, width=100, height = 20,text='Login',
state='normal',
command=lambda: controller.show_frame(RegEmailFrame)
self.loginBtn.grid(row=1, column=0)
class RegEmailFrame(tk.Frame):
def __init__(self, parent, controller,header_name="Register Email"):
tk.Frame.__init__(self, parent)
self.menu = Menu(self)
self.menu.grid(row=0, column=0)
self.emailLabel = ctk.CtKLabel(master=self,width=100, height=20 text='Frame swapped')
self.emailLabel.grid(row=1, column=0)
class Menu(tk.Frame):
def __init__(self, *args, header_name="Logo Frame",
width=175, height=175,**kwargs):
super().__init__(*args, width=width, height=height, **kwargs)
self.menuloginBtn = ctk.CTkButton(master=self, width=100, height = 20,text='Login',
state='normal',
command=lambda: controller.show_frame(LoginFrame)
self.menuloginBtn.grid(row=0, column=0)
self.menuRegBtn = ctk.CTkButton(master=self, width=100, height = 20,text='Login',
state='normal',
command=lambda: controller.show_frame(RegEmailFrame)
self.menuRegBtn.grid(row=1, column=0)
In the current implementation, the Menu class does not have access to the controller object that is used to switch between frames in the Login_Window class. One way to fix this would be to pass the controller object to the Menu class during instantiation.
You can do this by adding a parameter called controller in the Menu class constructor and then passing it as an argument when creating an instance of the Menu class in the LoginFrame and RegEmailFrame classes.
For example, in the LoginFrame class:
def __init__(self,parent, controller):
tk.Frame.__init__(self, parent)
self.menu = Menu(self, controller)
self.menu.grid(row=0, column=0)
And in the Menu class constructor:
def __init__(self, parent, controller, *args, header_name="Logo Frame",
width=175, height=175,**kwargs):
super().__init__(parent, *args, width=width, height=height, **kwargs)
self.controller = controller
With this changes, the Menu class now has access to the controller object and can use it to switch between frames using the show_frame method.
You should also make the same changes in the RegEmailFrame class and in the constructor of the Menu class.
Hope this helps!
I am new to python and GUI-Thinker. I'm learning about how to switch windows on GUI using Tkinker as UI, and python as a programming language.
I followed this guideline Switch between two frames in tkinter to switch frames in thinker and it worked.
Then, I'm trying to show widgets and hide all other widgets using bind("<<ComboboxSelected>>". But when I choose Monthly option, widgets as I set under DeleteOptions condition didn't show up. The same thing to Period option, widgets as I set under DeleteOptions condition didn't show up.
My Code:
from tkinter import *
import tkinter as tk
from tkinter import ttk
from tkinter import font as tkfont
from tkcalendar import DateEntry
class SampleApp(tk.Tk):
def __init__(self, *args, **kwargs):
tk.Tk.__init__(self, *args, **kwargs)
self.title_font = tkfont.Font(family='Helvetica', size=18, weight="bold", slant="italic")
# the container is where we'll stack a bunch of frames
# on top of each other, then the one we want visible
# will be raised above the others
container = tk.Frame(self)
container.pack(side="top", fill="both", expand=True)
container.grid_rowconfigure(0, weight=1)
container.grid_columnconfigure(0, weight=1)
self.frames = {}
for F in (StartPage, PageOne):
page_name = F.__name__
frame = F(parent=container, controller=self)
self.frames[page_name] = frame
# put all of the pages in the same location;
# the one on the top of the stacking order
# will be the one that is visible.
frame.grid(row=0, column=0, sticky="nsew")
self.show_frame("StartPage")
def show_frame(self, page_name):
'''Show a frame for the given page name'''
frame = self.frames[page_name]
frame.tkraise()
class StartPage(tk.Frame):
def __init__(self, parent, controller):
tk.Frame.__init__(self, parent)
self.controller = controller
label = tk.Label(self, text="This is the start page", font=controller.title_font)
label.pack(side="top", fill="x", pady=10)
button1 = tk.Button(self, text="Go to Page One",
command=lambda: controller.show_frame("PageOne"))
button1.pack()
class PageOne(tk.Frame):
def __init__(self, parent, controller):
tk.Frame.__init__(self, parent)
self.controller = controller
label = tk.Label(self, text="This is page 1", font=controller.title_font)
label.grid()
button = tk.Button(self, text="Go to the start page",
command=lambda: controller.show_frame("StartPage"))
button.grid()
def DeleteOptions():
if SVcmb_Delete.current()=="Monthly":
HideDeleteOptions()
lblMonthly.grid(row=4)
SVcmb_Monthly.grid(row=4, column=1)
if SVcmb_Delete.current()=="Period":
HideDeleteOptions()
lblFrom.grid(row=4)
txtFrom.grid(row=4, column=1)
lblTo.grid(row=5)
txtTo.grid(row=5, column=1)
lblSV_Search=tk.Label(self,text="Delete by")
lblSV_Search.grid(row=3)
SVcmb_Delete=ttk.Combobox(self,state="readonly",justify=CENTER,font=("times new roman",15))
SVcmb_Delete["values"]=("Select","Monthly","Period")
SVcmb_Delete.grid(row=3,column=1)
SVcmb_Delete.bind("<<ComboboxSelected>>", lambda event:DeleteOptions)
def HideDeleteOptions():
lblMonthly.grid_forget()
SVcmb_Monthly.grid_forget()
lblFrom.grid_forget()
txtFrom.grid_forget()
lblTo.grid_forget()
txtTo.grid_forget()
lblMonthly=tk.Label(self,text="Monthly")
SVcmb_Monthly=ttk.Combobox(self,state="readonly",values=[1,2,3],justify=CENTER)
lblFrom=tk.Label(self,text="From")
txtFrom=DateEntry(self,selectmode='day',date_pattern='mm/dd/y')
lblTo=tk.Label(self,text="To")
txtTo=DateEntry(self,selectmode='day',date_pattern='mm/dd/y')
if __name__ == "__main__":
app = SampleApp()
app.mainloop()
On page one. I'm looking for a way like when I chose Monthly option, all widgets under DeleteOptions condition show up and all widgets of Period option are hidden as I set under DeleteOptions condition. The same thing to Period option, all widgets under DeleteOptions condition show up and all widgets of Monthly option are hidden as I set under DeleteOptions condition.
Please help me. Thank you so much.
There are two problems with your code. This first is with your lambda expression:
SVcmb_Delete.bind("<<ComboboxSelected>>", lambda event:DeleteOptions)
is wrong because it doesn't actually call the DeleteOptions() function the way it's written.
Instead, do it like this:
SVcmb_Delete.bind("<<ComboboxSelected>>", lambda event: DeleteOptions())
The second problem is with your use of the SVcmb_Delete.current() method in the DeleteOptions() function because it returns the index of the the current entry text, not the entry text itself. To obtain that, you should use the get() method. With that correction made the function should look like something like this:
def DeleteOptions():
if SVcmb_Delete.get() == "Monthly":
HideDeleteOptions()
lblMonthly.grid(row=4)
SVcmb_Monthly.grid(row=4, column=1)
if SVcmb_Delete.get() == "Period":
HideDeleteOptions()
lblFrom.grid(row=4)
txtFrom.grid(row=4, column=1)
lblTo.grid(row=5)
txtTo.grid(row=5, column=1)
Lastly I also strongly suggest that you read and start following the PEP 8 - Style Guide for Python Code to make your code more readable.
I copied Python code to create a Tkinter window with multiple frames. I put many kinds of widgets into it with no problem but when I add radiobuttons, those act funny, although they work fine in a regular window (without multiple pages). Whether I set the value or not, none of the radiobuttons are selected. What's worse, if I just pass the mouse pointer over a radiobutton, it looks like it gets selected although I didn't click it. If I pass the mouse pointer over both radiobuttons, they BOTH look selected, violating the one-of-many-selections rule of radiobuttons.
I should add that I tried this with a pack manager and with a grid manager. The results are the same.
Here's a stripped-down version of my code:
import tkinter as tk
class MainWindow(tk.Tk):
def __init__(self, *args, **kwargs):
tk.Tk.__init__(self, *args, **kwargs)
# Set the title of the main window.
self.title('Multi-frame window')
# Set the size of the main window to 300x300 pixels.
self.geometry('300x100')
# This container contains all the pages.
container = tk.Frame(self)
container.grid(row=1, column=1)
self.frames = {} # These are pages to which we want to navigate.
# For each page...
for F in (StartPage, PageOne):
# ...create the page...
frame = F(container, self)
# ...store it in a frame...
self.frames[F] = frame
# ..and position the page in the container.
frame.grid(row=0, column=0, sticky='nsew')
# The first page is StartPage.
self.show_frame(StartPage)
def show_frame(self, name):
frame = self.frames[name]
frame.tkraise()
class StartPage(tk.Frame):
def __init__(self, parent, controller):
tk.Frame.__init__(self, parent)
label = tk.Label(self, text='Start Page')
label.grid(row=1, column=1)
# When the user clicks on this button, call the
# show_frame method to make PageOne appear.
button1 = tk.Button(self, text='Visit Page 1',
command=lambda : controller.show_frame(PageOne))
button1.grid(row=2, column=1)
class PageOne(tk.Frame):
def __init__(self, parent, controller):
tk.Frame.__init__(self, parent)
# When the user clicks on this button, call the
# show_frame method to make StartPage appear.
button1 = tk.Button(self, text='Back to Start',
command=lambda : controller.show_frame(StartPage))
button1.grid(row=1, column=1)
options_label = tk.Label(self, text='Choose an option: ')
options_label.grid(row=2, column=1)
options_value = tk.IntVar()
first_option = tk.Radiobutton( self , text = 'Option 1' ,
variable = options_value , value = 1 )
second_option = tk.Radiobutton( self , text = 'Option 2' ,
variable = options_value , value = 2 )
first_option.grid(row=2, column=2)
second_option.grid(row=2, column=3)
options_value.set(1)
if __name__ == '__main__':
app = MainWindow()
app.mainloop()
The problem is that options_value is a local value that gets destroyed when __init__ finishes.
You need to save a reference to it, such as self.options_value.
I'm very new to the world of GUIs with Python and attempting to build my first one with multiple pages, but sharing a variable from an entry box is really throwing me through a loop. I understand there's probably a lot wrong with the code, but for now, I would really just like to better understand how to share the variables between the pages from the username entry box.
Here is the code that ties into this:(The page breaks are just where there is some unrelated code)
import tkinter as tk
from tkinter import Tk, Label, Button, StringVar
class Keep(tk.Tk):
def __init__(self, *args, **kwargs):
tk.Tk.__init__(self, *args, **kwargs)
self.shared_data ={
"email": tk.StringVar(),
"password": tk.StringVar()
}
# Skipping some code to get to the good stuff
class StartPage(tk.Frame):
def __init__(self, parent, controller):
tk.Frame.__init__(self, parent)
self.controller = controller
# LABELS, ENTRIES, AND BUTTONS
# page break
self.entry1 = tk.Entry(self, textvariable=self.controller.shared_data["email"])
entry2 = tk.Entry(self, show = '*')
button1 = tk.Button(text="Submit", command=lambda: [controller.show_frame("PageTwo"), self.retrieve()])
# page break
def retrieve(self):
self.email = self.controller.shared_data["email"].get()
self.controller.email = self.email
class PageTwo(tk.Frame):
def __init__(self, parent, controller):
tk.Frame.__init__(self, parent)
self.controller = controller
self.email = self.controller.shared_data["email"].get()
label1 = tk.Label(self, text="Welcome, {}".format(self.email))
if __name__ == "__main__":
keep = Keep()
keep.mainloop()
I know the retrieve function looks pretty funky and probably not at all correct, but I've been working on this specific problem for about a week now and it has lead me down some wild rabbit holes.
The end goal is for label1 of pageTwo to display, "Welcome, (insert e-mail entered in entry1 of startPage)".
I think my issue lies with pageTwo retrieving an empty string from shared_data, but I don't understand why that is.
Any help is super appreciated!
I guess problem is because frames are created in Keep.__init__, not when you run show_frame(), so PageTwo.__init__() is executed at start and text Welcome... is create at start - before you even see StartPage.
You should create empty label in __init__ and create text Welcome... in other method (ie. update_widgets()) which you will execute after show_frame() or event inside show_frame() if all classes will have update_widgets()>
Minimal working code:
import tkinter as tk
class Keep(tk.Tk):
def __init__(self, *args, **kwargs):
super().__init__(*args, **kwargs)
self.shared_data ={
"email": tk.StringVar(),
"password": tk.StringVar()
}
self.frames = {
'StartPage': StartPage(self, self),
'PageTwo': PageTwo(self, self),
}
self.current_frame = None
self.show_frame('StartPage')
def show_frame(self, name):
if self.current_frame:
self.current_frame.forget()
self.current_frame = self.frames[name]
self.current_frame.pack()
self.current_frame.update_widgets() # <-- update data in widgets
class StartPage(tk.Frame):
def __init__(self, parent, controller):
super().__init__(parent)
self.controller = controller
self.entry1 = tk.Entry(self, textvariable=self.controller.shared_data["email"])
self.entry1.pack()
entry2 = tk.Entry(self, show='*')
entry2.pack()
button = tk.Button(self, text="Submit", command=lambda:controller.show_frame("PageTwo"))
button.pack()
def update_widgets(self):
pass
class PageTwo(tk.Frame):
def __init__(self, parent, controller):
super().__init__(parent)
self.controller = controller
self.label = tk.Label(self, text="") # <-- create empty label
self.label.pack()
def update_widgets(self):
self.label["text"] = "Welcome, {}".format(self.controller.shared_data["email"].get()) # <-- update text in label
if __name__ == "__main__":
keep = Keep()
keep.mainloop()
I have made a function in the main constructor of my tKinter app which updates certain properties of widgets e.g. their text across multiple frames. What I'm trying to do is change widgets in multiple frames at the same time while in a controller frame.
def update_widgets(self, frame_list, widget_name, criteria, output):
for i in frame_list:
i.widget_name.config(criteria=output)
# update_widgets(self, [Main, AnalysisSection], text_label, text, "foo")
# would result in Main.text_label_config(text="foo") and
# AnalysisSection.text_label_config(text="foo") ideally.
However with this code, I'm encountering two problems. Firstly, I'm getting an attribute error stating that both frames don't have the attribute widget_name. Secondly, when I tried to refer to the widget names with the self prefix, both frames say they don't have the attribute self. Is there a way to fix this?
Full program below:
import tkinter as tk
class Root(tk.Tk):
def __init__(self, *args, **kwargs):
tk.Tk.__init__(self, *args, **kwargs)
self.frames = {}
container = tk.Frame(self)
container.pack(side="bottom", expand=True)#fill="both", expand=True)
container.grid_rowconfigure(0, weight=1)
container.grid_columnconfigure(0, weight=1)
for X in (A, B):
frame=X(container, self)
self.frames[X]=frame
frame.grid(row=0, column=0, sticky="nsew")
self.show_frame(A)
def show_frame(self, page):
frame = self.frames[page]
frame.tkraise()
def update_widgets(self, frame_list, widget_name, criteria, output):
for i in frame_list:
frame = self.frames[i]
widget = getattr(frame, widget_name)
widget[criteria] = output
class A(tk.Frame):
def __init__(self, parent, controller):
tk.Frame.__init__(self, parent)
self.controller = controller
self.text = 'hello'
self.classLabel = tk.Label(self, text="Frame A")
self.classLabel.pack(side=tk.TOP)
# trying to change this widget
self.wordLabel = tk.Label(self, text="None")
self.wordLabel.pack(side=tk.TOP)
self.changeTextLabel = tk.Label(self, text="Change text above across both frames").pack(side=tk.TOP)
self.changeTextEntry = tk.Entry(self, bg='pink')
self.changeTextEntry.pack(side=tk.TOP)
self.changeFrameButton = tk.Button(text="Change to Frame B", command=lambda: self.controller.show_frame(B))
self.changeFrameButton.pack(side=tk.TOP, fill=tk.X)
self.changeTextEntryButton = tk.Button(self, text="ENTER", width=5, command=lambda: self.controller.update_widgets([A, B], 'self.wordLabel', 'text', self.changeTextEntry.get()))
self.changeTextEntryButton.pack(side=tk.TOP, fill=tk.X)
### calling this function outside of the button; this is already
### called within a function in my project.
x = self.controller.update_widgets([A, B], 'wordLabel', 'text', '*initial change*')
class B(tk.Frame):
def __init__(self, parent, controller):
tk.Frame.__init__(self, parent)
self.controller = controller
self.text = 'hello'
self.classLabel = tk.Label(self, text="Frame B")
self.classLabel.pack(side=tk.TOP)
# trying to change this widget
self.wordLabel = tk.Label(self, text="None")
self.wordLabel.pack(side=tk.TOP)
self.changeTextLabel = tk.Label(self, text="Change text above across both frames").pack(side=tk.TOP)
self.changeTextEntry = tk.Entry(self, bg='light yellow').pack(side=tk.TOP)
self.changeFrameButton = tk.Button(text="Change to Frame A", command=lambda: self.controller.show_frame(A))
self.changeFrameButton.pack(side=tk.TOP, fill=tk.X)
self.changeTextEntryButton = tk.Button(self, text="ENTER", width=5, command=lambda: self.controller.update_widgets([A, B], 'self.wordLabel', 'text', self.changeTextEntry.get()))
self.changeTextEntryButton.pack(side=tk.TOP, fill=tk.X)
if __name__ == '__main__':
app = Root()
The problem in your code is that you're trying to get an attribute of a class rather than an instance of a class. You need to convert i to the actual instance of that class. You have the additional problem that you're passing 'self.wordLabel' rather than just 'wordLabel'.
A simple fix is to look up the instance in self.frames
def update_widgets(self, frame_list, widget_name, criteria, output):
for i in frame_list:
frame = self.frames[i]
label = getattr(frame, widget_name)
label[criteria] = output
You also need to change the button command to look like this:
self.changeTextEntryButton = tk.Button(... command=lambda: self.controller.update_widgets([A,B], 'wordLabel', 'text', self.changeTextEntry.get()))
If you intend for update_widgets to always update all of the page classes, there's no reason to pass the list of frame classes in. Instead, you can just iterate over the known classes:
def update_widgets(self, widget_name, criteria, output):
for frame in self.frames.values():
label = getattr(frame, 'classLabel')
label[criteria] = output
You would then need to modify your buttons to remove the list of frame classes:
self.changeTextEntryButton = tk.Button(..., command=lambda: self.controller.update_widgets('wordLabel', 'text', self.changeTextEntry.get()))