CODEWITHSUNDEEP
pythontkinter
Ga Mmeeu
Ga Mmeeu

Reputation: 325

Tkinter: get variable from one frame to show as label in another frame

Reference is made to How to get variable data from a class

For convenience the code from the above mentioned post is repeated at the bottom in consolidated form.

This code passes a variable entered in Frame PageOne to PageTwo, and when the button is pressed, the variable is printed to the console.

Without success, I have been trying to set the label of PageTwo to show the variable entered on PageOne. Initially, I hoped that the code modification would be as simple as:

class PageTwo(ttk.Frame):
    def __init__(self, parent, controller):
        self.controller=controller  
        ttk.Frame.__init__(self, parent)
        ttk.Label(self, text='PageTwo').grid(padx=(20,20), pady=(20,20))
        ...

changing the last line to:

        ttk.Label(self, text=self.controller.app_data["name"].get()).grid(padx=(20,20), pady=(20,20))

I have tried various combinations using ideas from different posted, but it seems I am missing some fundamental reasoning. Any help would be very much appreciated by this newbie.

Full code consolidated from the above referenced post:

#!/usr/bin/python

from Tkinter import *
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 = {}
    self.app_data = {"name":    StringVar(),
                         "address": StringVar()
                        }
        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):
    self.controller=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.controller.app_data["name"], 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):
    self.controller=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):
    value = self.controller.app_data["name"].get()
        print "The value stored in StartPage some_entry = ",value


app = MyApp()
app.title('Multi-Page Test App')
app.mainloop()

Upvotes: 2

Views: 2021

Answers (2)

10SecTom
10SecTom

Reputation: 2664

As mentioned by figbeam, when you switch frame it is already created. I did an edit to update the label when the button is pressed.

class PageTwo(ttk.Frame):
        def __init__(self, parent, controller):
            self.controller=controller  
            ttk.Frame.__init__(self, parent)
            self.label = ttk.Label(self, text='PageOne')
            self.label.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):
            value = self.controller.app_data["name"].get()
            print ("The value stored in StartPage some_entry = %s", value)
            self.label['text'] = value

Alternatively, you could use the same string var for your label in page two:

ttk.Label(self, textvariable=self.controller.app_data["name"]).grid(padx=(20,20), pady=(20,20))

Upvotes: 2

figbeam
figbeam

Reputation: 7176

You create the label for page two from MyApp.__init__() which invokes PageTwo.__init__(), before anything is entered into the entry on page one.

You'll have to update the label when you switch frames.

Upvotes: 2

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