Prerequisites: Python GUI – tkinter
The Listbox widget is used to display a list of items from which a user can select a number of items. But have you ever wondered, how to return the list of possible results when a key is pressed? Let’s see the following approach towards the same.
Working of Program
- List consisting of words is initialized.
- Entry box and Listbox are created and are added to the root window.
- Bind function is used for event handling. Key release event is handled for an Entry field.
- When any key is pressed in the Entry,
checkkey()function is called. checkkey()function then compares the entered string with existing list keywords and populates Listbox with matching keywords.- Then this data is sent to update function which then updates the Listbox.
Below is the approach.
from tkinter import * # Function for checking the # key pressed and updating # the listbox def checkkey(event): value = event.widget.get() print(value) # get data from l if value == '': data = l else: data = [] for item in l: if value.lower() in item.lower(): data.append(item) # update data in listbox update(data) def update(data): # clear previous data lb.delete(0, 'end') # put new data for item in data: lb.insert('end', item) # Driver code l = ('C','C++','Java', 'Python','Perl', 'PHP','ASP','JS' ) root = Tk() #creating text box e = Entry(root) e.pack() e.bind('<KeyRelease>', checkkey) #creating list box lb = Listbox(root) lb.pack() update(l) root.mainloop() |
Output:
