Accessing variable from outside the function in GUI (Tkinter) Python

Question

I have a simple GUI in python. I want to print the value entered by the user from outside the function. The code I made is given below

def save_BasePath():

    Base_Path_info = Base_Path.get()
    #print(Base_Path_info)

    file_basepath = open("basepath.txt", "w")

    file_basepath.write(str(Base_Path_info))


    file_basepath.close()

app = Tk()
app.geometry("500x500")

app.title("Python File Handling in Forms")

heading = Label(text="Input Print", fg="black", bg="yellow", width="500",
                height="3", font="10")

heading.pack()

Base_Path_text = Label(text="Base_Path :")
Base_Path_text.place(x=155, y=70)
Base_Path = StringVar()
Base_Path_entry = Entry(textvariable=Base_Path, width="30")
Base_Path_entry.place(x=155, y=100)
button_basepath = Button(app, text="Enter Base Path", command=save_BasePath, width="15", height="2", bg="grey")
button_basepath.place(x=175, y=125)

#I need the user input from the function here so that I can use it further

mainloop()

On Pressing the button, I get the user input. I am able to print from within the save_basepath function. But I want to access the user input from outside so that I can work on it. Any help is appreciated

Answer 1

we can use the global keyword:

from tkinter import *
def save_BasePath():
    global Base_Path_info
    Base_Path_info = Base_Path.get()
    #print(Base_Path_info)

    file_basepath = open("basepath.txt", "w")

    file_basepath.write(str(Base_Path_info))


    file_basepath.close()
    print_it()

def print_it():
    print(Base_Path_info)

app = Tk()
app.geometry("500x500")

app.title("Python File Handling in Forms")

heading = Label(text="Input Print", fg="black", bg="yellow", width="500",
                height="3", font="10")

heading.pack()

Base_Path_text = Label(text="Base_Path :")
Base_Path_text.place(x=155, y=70)
Base_Path = StringVar()
Base_Path_entry = Entry(textvariable=Base_Path, width="30")
Base_Path_entry.place(x=155, y=100)
button_basepath = Button(app, text="Enter Base Path", command=save_BasePath, width="15", height="2", bg="grey")
button_basepath.place(x=175, y=125)

#I need the user input from the function here so that I can use it further


mainloop()

But keep in mind that we want to avoid this, and the best way to do that is by using a class.

Here is how I would do it:

from tkinter import *

class myProgram:
    def __init__(self):
        heading = Label(text="Input Print", fg="black", bg="yellow", width="500",
                        height="3", font="10")

        heading.pack()

        Base_Path_text = Label(text="Base_Path :")
        Base_Path_text.place(x=155, y=70)
        self.Base_Path = StringVar()
        Base_Path_entry = Entry(textvariable=self.Base_Path, width="30")
        Base_Path_entry.place(x=155, y=100)
        button_basepath = Button(app, text="Enter Base Path", command=self.save_BasePath, width="15", height="2", bg="grey")
        button_basepath.place(x=175, y=125)

    def save_BasePath(self):
        self.Base_Path_info = self.Base_Path.get()

        file_basepath = open("basepath.txt", "w")

        file_basepath.write(str(self.Base_Path_info))


        file_basepath.close()
        self.print_it()

    def print_it(self):
        print(self.Base_Path_info)
        
        # Continue your code here...


app = Tk()
app.geometry("500x500")

app.title("Python File Handling in Forms")
myProgram()
mainloop()