How to Clear the Text Field Part of ttk.Combobox in Tkinter?
Tkinter is the standard GUI library for Python. It provides a set of powerful widgets to create desktop applications. ttk.Combobox
is one of the most common widgets used in GUI applications. It is a combination of an entry field and a drop-down list. The user can select an item from the list or type in their own text. But, what if you want to clear the text field part of the ttk.Combobox
programmatically? In this article, we will see how to achieve that.
The Problem
The ttk.Combobox
widget has two parts – the text field and the drop-down list. The text field is where the user can type in their own text. In some cases, you may want to clear the text field programmatically. For example, you may want to reset the ttk.Combobox
to its initial state or clear the text field after a successful selection from the drop-down list.
Example
Here is a simple example of ttk.Combobox
widget.
import tkinter as tk
from tkinter import ttk
root = tk.Tk()
combobox = ttk.Combobox(root, values=['Apple', 'Banana', 'Cherry'])
combobox.pack()
root.mainloop()
This will create a ttk.Combobox
widget with three items in the drop-down list – Apple, Banana, and Cherry.
The Solution
To clear the text field part of the ttk.Combobox
, you need to delete the text that was entered by the user. You can achieve this by using the delete()
method of the ttk.Entry
widget.
The ttk.Combobox
widget has a hidden ttk.Entry
widget that is used to handle the user’s input. You can access this widget using the combobox.children['!entry']
notation. Once you have access to the ttk.Entry
widget, you can use the delete()
method to clear the text field.
Here is the modified example that clears the text field of the ttk.Combobox
when the user selects an item from the drop-down list.
import tkinter as tk
from tkinter import ttk
root = tk.Tk()
def on_select(event):
combobox = event.widget
index = combobox.current()
value = combobox.get()
print(f'Selected item: {value}')
combobox.children['!entry'].delete(0, tk.END)
combobox = ttk.Combobox(root, values=['Apple', 'Banana', 'Cherry'])
combobox.pack()
combobox.bind('<<ComboboxSelected>>', on_select)
root.mainloop()
In this example, we have added a new function on_select
that gets called when the user selects an item from the drop-down list. The event
argument contains information about the event, including the widget that triggered the event (event.widget
). We can get the selected item using the current()
and get()
methods of the ttk.Combobox
widget.
After printing out the selected item, we use the delete()
method of the ttk.Entry
widget to clear the text field. The delete()
method takes two arguments – the starting and ending index of the text to delete. In this case, we want to delete the entire text, so we use 0
as the starting index and tk.END
as the ending index.
Now, when the user selects an item, the text field will be cleared automatically.
Conclusion
In this article, we have seen how to clear the text field part of the ttk.Combobox
widget in Tkinter. We have learned that ttk.Combobox
has a hidden ttk.Entry
widget that can be accessed using the combobox.children['!entry']
notation. With this knowledge, we can use the delete()
method of the ttk.Entry
widget to clear the text field programmatically.