How to set a default string value on a Tkinter Spinbox?
Tkinter is a popular Python GUI library that helps create interactive interfaces. However, the Spinbox widget might be slightly different from the regular text box as they allow specific values to be selected.
A Spinbox can be used to select values within a specific range, or we can use it as a way to select a value from a set of predetermined values. By default, Spinbox in Tkinter is used for numeric values, but it can also be used for strings or alphanumeric values.
Sometimes, while designing GUIs, there might be a need to set a default value in a Spinbox widget. In this article, we will learn how to set a default string value on a Tkinter Spinbox widget.
Creating the Tkinter Spinbox
Let’s first create a Spinbox widget in Tkinter. We can do this via the Spinbox()
function, which accepts various arguments like from_
, to
, increment
, and values
among others. In this article, we will use the values
argument for a fixed set of options.
import tkinter as tk
root = tk.Tk()
# Creating a Spinbox widget
spinbox_options = ["One", "Two", "Three", "Four", "Five"]
default = "One"
spinbox_var = tk.StringVar(root, default)
spinbox = tk.Spinbox(root, values=spinbox_options, textvariable=spinbox_var)
spinbox.pack()
root.mainloop()
The above code creates a Spinbox with five options – “One”, “Two”, “Three”, “Four”, and “Five”. We have also set the default value of the Spinbox to be “One”. Note that the default value has been set using the textvariable
argument, which uses a StringVar
with the value of default
.
Changing the Default Value
In certain scenarios, we might want to change the default value of the Spinbox based on a user action. In such cases, we can set the value of the StringVar
to the new default value.
new_default = "Four"
spinbox_var.set(new_default)
The above code sets the value of the StringVar
to “Four”, which will reflect on the GUI.
Conclusion
Setting a default value for a Spinbox widget is pretty easy in Tkinter. We can make use of the textvariable
argument to set the initial value of the Spinbox, and we can modify it later using the set()
method of the StringVar
. Hope this article helps in implementing Spinbox widgets with default values in your GUIs.