Tkinter Combobox

Introduction to Tkinter Combobox

The Tkinter Combobox is one of the UI widgets in the Tkinter library and it is used for to select the values in the drop-down list column also it is one of the combinations of Entry and drop-down widgets these drop-down entries are replaceable one and the user if suppose not select the value in the box it automatically fetches and view the default value on the screen the Tkinter module used standard library functions and also the Tk interface is most prominently used for all the GUI based widgets the Combobox select option arrow automatically scrolls down when the user is searching the particular value in the field.

Syntax:

The Tkinter module most powerful GUI-based widget and it has followed with the Tk interface also it has most advanced library methods in the python. It has more number of global methods hence Combobox() also one of the widgets and globalizes methods it can be used to directly on the specific functions and behavior of the application. It has its own syntax and default parameters.

import tkinter as tk
from tkinter import ttk
variable name=Tk()
ttk.Label(window, text=””, …)
variable name=ttk.Combobox(variable name, width=, text= )
variable name.mainloop()

The above code is the basic syntax of the Combobox Tkinter library. We have called the UI items like label, textbox, etc based on the requirement we will proceed it for further steps to enhancement the application.

How Combobox Works in Tkinter?

The Tkinter module has a different set of widgets in the library this package has a set of built-in functions that have been used for covering the UI parts in the web application. It has the most interactive and advanced library it can be calculated the functionalities for the time, speed and weather calculations, some scientific calculations, etc even though some AI-based functionality also covered in these widgets. The UI widget has buttons, views, scroll box, list box, combo box, etc mostly button will be covered the UI part to navigate the web pages or applications. Once we clicked the button it operates and works the backend areas code that can be covered to the user-defined logic. When we use these combo boxes lists the user can be chosen the entry values and these entries are scrolled down using the drop-down option and the arrow symbol will be used on the left side of the area that will drop-down the values and menus are choosing and showing the choices. And these choices are clicked by the user if the user is not choosing any values it takes the default value based on the code logic on the front end and backend.

If the user selects any values of the combo list box again the value will be replaceable if the user needs it. The Combobox has a different set of parameters will be passed and the attributes like font-family, size, weight, colors, etc these type of attribute are passing to the Combobox() also Tkinter have a default font it could be more specified with the tuple side of options. The Tkinter combobox used event binding feature while we used Combobox callback function binding and these data binding will be called using the combobox virtual events. These events will be used for the user while selecting the values in the drop-down list box. While we used these events and these events will be passed to the specific function like callback function. The combobox has another option called <comboboxSelected> option it’s used for binding the virtual events while we used callback functions on the script. The list of values in the combo box could be dynamically generated and it’s updated using the option and commands called post command it executes the predefined function before executing the pop-down list of values in the apps.

The combobox elements contains the default text box fields and these box elements are to be editable and it mostly used in the pre-defined state as normal. Also, the Combobox has two different states before the normal state 1.readonly and 2.disabled.The read-only state is used in the text field area is mostly non-editable and the user will choose only the values in the drop-down list box. In the default state, the combobox is grayed out and the user interaction is not possible in these states but when we used read-only state user-friendly nature but its not possible in the default state.

Examples

Lets us discuss the examples of Tkinter Combobox.

Example 1

from tkinter import *  
import tkinter as tk
from tkinter import ttk
user = Tk()  
uname = Label(user,text = "uname").grid(row =1, column = 1)  
un= Entry(user).grid(row = 0, column = 0)  
passw = Label(user,text = "pass").grid(row = 1, column = 1)  
ps = Entry(user).grid(row = 1, column = 1)  
result = Button(user, text = "submit").grid(row = 3, column = 3)  
comb = tk.Label(user,
                    text = "Please select the option")
comb.grid(column=2, row=1)

example = ttk.Combobox(user, 
                            values=[
                                    "first", 
                                    "second",
                                    "third",
                                    "four"])
print(dict(example))  
example.grid(column=2, row=2)
example.current(3)
user.mainloop()  

Output:

 Example 2

import tkinter as tk
from tkinter import ttk
def demo(events):
     print("Please select the new events from the list")   
first = tk.Tk() 
first.geometry('310x110')
def month():
    example["values"] = ["first",
                        "second",
                        "third",
                        "four"
                           ]
lists = tk.Label(first,
                    text = "Welcome User please select list of values")
lists.grid(column=5, row=5)
example = ttk.Combobox(first, 
                            values=[
                                    "first", 
                                    "second",
                                    "third",
                                    "four"],
                            postcommand=month)
example.grid(column=5, row=5)
first.mainloop()

Output:

Example 3

from tkinter import *
from tkinter import *  
import tkinter as tk
from tkinter import ttk
user = Tk()  
uname = Label(user,text = "uname", background = 'violet', foreground ="violet",  
          font = ("Times New Roman", 13)).grid(row =1, column = 1)  
un= Entry(user).grid(row = 0, column = 0)  
passw = Label(user,text = "pass", background = 'blue', foreground ="blue",  
          font = ("Times New Roman", 13)).grid(row = 1, column = 1)  
ps = Entry(user).grid(row = 1, column = 1)  
result = Button(user, text = "submit").grid(row = 3, column = 3)  
comb = tk.Label(user,
                    text = "Please select the option",background = 'pink', foreground ="pink",  
          font = ("Times New Roman", 17))
comb.grid(column=2, row=1)

example = ttk.Combobox(user, 
                            values=[
                                    "first", 
                                    "second",
                                    "third",
                                    "four"])
print(dict(example))  
example.grid(column=2, row=2)
example.current(3)
user.mainloop()

Output:

Conclusion

In the conclusion part, the above concepts and examples for the combo box are the basic and usages of the python application. It can be varied and it depends upon the user requirement which widgets and mainly combo box option the values are fetching from the backend if the application is connected to the database also it’s changed dynamically based on the user-chosen option. So it’s one of the user-friendly widgets of the Tkinter library in the python.

Recommended Articles

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2. Tkinter Scrollbar
3. Tkinter Text
4. Python Tkinter Entry