Is there a way to save the input (float) from a variable created in a user interface in Python?

Question

I have been trying to make a user interface (by using tkinter)in Python that saves the number you enter. In this case I want the user to be able to give a start value and an end value of a measurement, which afterwards will be implemented in a code. For this to work, I need the user interface to be able to store the values I enter. However, so far I haven't be able to export my variables with the assigned values. I only managed to get the variables with value 0. Could someone please help me figure out my mistake? Thanks in advance!

Here is the code I used:

import tkinter as tk
import tkinter.messagebox

root = tk.Tk()
tk.Label(root, text = "Start of measurement (index): ")
tk.Label(root, text = "End of measurement (index): ")

def add_text():
       label1 = tk.Label(root, text="You have entered the start and end index of the measurement")
       label1.pack()



Start = tk.DoubleVar(root)
End = tk.DoubleVar(root)

Start_measurement = Start.get()
End_measurement = End.get()

Start_label = tk.Label(root, text="Start of measurement (index): ")
Start_label.pack()

Start_text_box = tk.Entry(root, bd=1)
Start_text_box.pack()

End_label = tk.Label(root, text="End of measurement (index): ")
End_label.pack()

End_text_box = tk.Entry(root, bd=1)
End_text_box.pack()

enter_button = tk.Button(root, text="Enter", command=add_text)
enter_button.pack()


root.mainloop()

Does this answer your question? Convert Tkinter textbox entry into Python Variable … get() the values in the button's commad function. — wwii
– wwii, Commented Jan 2, 2020 at 15:21

KJTHoward · Accepted Answer · 2020-01-02 15:30:16Z

1

It would be variable = Start_text_box.get() or variable = End_text_box.get().

Also to close the windows for later use in your code you need to do

root.quit()
root.withdraw()

For example:

def add_text():
    globals()['START']=Start_text_box.get()
    globals()['END']=End_text_box.get()
    print("Start was ", START)
    print("End was ", END)
    root.quit()
    root.withdraw()

The globals() is there because the START/END variables are defined within a local function so to use them elsewhere you need to assign them globally.

answered Jan 2, 2020 at 15:30

KJTHoward

8614 silver badges18 bronze badges

Sign up to request clarification or add additional context in comments.

2 Comments

Pallas Athena Over a year ago

Thanks for your answer and explanation KJTHoward! I tried it and it worked :-)

KJTHoward Over a year ago

@PallasAthena No problem, happy to help :). Feel free to mark this post as an answer to your question so the question is listed as answered and if anyone else has a similar problem they can find the solution.

Toto · Accepted Answer · 2020-01-02 15:27:08Z

1

In your add_text function you could first get the string of the textbox:

val1 = Start_text_box.get()

Then convert it to double:

val1 = float(val1)

Then print it

label1 = tk.Label(root, text="You have entered the start {0} and end index of the measurement".format(val1))

answered Jan 2, 2020 at 15:27

Toto

991 silver badge12 bronze badges

1 Comment

Pallas Athena Over a year ago

Thank you for your advice Toto, the code works now :-)

Collectives™ on Stack Overflow

Is there a way to save the input (float) from a variable created in a user interface in Python?

2 Answers 2

2 Comments

1 Comment

Your Answer

Linked

Hot Network Questions

Collectives™ on Stack Overflow

2 Answers 2

2 Comments

1 Comment

Your Answer

Sign up or log in

Post as a guest

Linked

Related