Python Programming/Tkinter

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Tkinter is a Python wrapper for Tcl/Tk providing a cross-platform GUI toolkit. On Windows, it comes bundled with Python; on other operating systems, it can be installed. The set of available widgets is smaller than in some other toolkits, but since Tkinter widgets are extensible, many of the missing compound widgets can be created using the extensibility, such as combo box and scrolling pane.

IDLE, Python's Integrated Development and Learning Environment, is written using Tkinter and is often distributed with Python. You can learn about features of Tkinter by playing around with menus and dialogs of IDLE. For instance, Options > Configure IDLE... dialog shows a broad variety of GUI elements including tabbed interface. You can learn about programming using Tkinter by studying IDLE source code, which, on Windows, is available e.g. in C:\Program Files\Python27\Lib\idlelib.

Python 3: The examples on this page are for Python 2. In Python 3, what was previously module Tkinter is tkinter, what was tkMessageBox is messagebox, etc.

Minimal example[edit]

A minimal example:

from Tkinter import *
root = Tk()
frame = Frame(root)
frame.pack()
label = Label(frame, text="Hey there.")
label.pack()
quitButton = Button(frame, text="Quit", command=frame.quit)
quitButton.pack()
root.mainloop()

A minimal example made more compact - later references to GUI items not required:

from Tkinter import *
root = Tk()
frame = Frame(root)
frame.pack()
Label(frame, text="Hey there.").pack()
Button(frame, text="Quit", command=frame.quit).pack()
root.mainloop()

A minimal example creating an application class derived from Frame:

from Tkinter import *

class App(Frame):
  def __init__(self, master):
    Frame.__init__(self)
    self.label = Label(master, text="Hey there.")
    self.label.pack()    
    self.quitButton = Button(master, text="Quit", command=self.quit)
    self.quitButton.pack()

if __name__ == '__main__':
  root = Tk()
  app = App(root)
  root.mainloop()

Message boxes[edit]

Simple message boxes can be created using tkMessageBox as follows:

import Tkinter, tkMessageBox
Tkinter.Tk().withdraw() # Workaround: Hide the window
answer = tkMessageBox.askokcancel("Confirmation", "File not saved. Discard?")
answer = tkMessageBox.askyesno("Confirmation", "Do you really want to delete the file?")
# Above, "OK" and "Yes" yield True, and "Cancel" and "No" yield False
tkMessageBox.showwarning("Warning", "Timeout has elapsed.")
tkMessageBox.showwarning("Warning", "Timeout has elapsed.", icon=tkMessageBox.ERROR)
tkMessageBox.showerror("Warning", "Timeout has elapsed.")

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File dialog[edit]

File dialogs can be created as follows:

import Tkinter, tkFileDialog
Tkinter.Tk().withdraw() # Workaround: Hide the window
filename1 = tkFileDialog.askopenfilename()
filename2 = tkFileDialog.askopenfilename(initialdir=r"C:\Users")
filename3 = tkFileDialog.asksaveasfilename()
filename4 = tkFileDialog.asksaveasfilename(initialdir=r"C:\Users")
if filename1 <> "":
  for line in open(filename1): # Dummy reading of the file
    dummy = line.rstrip()

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Radio button[edit]

A radio button can be used to create a simple choice dialog with multiple options:

from Tkinter import *
master = Tk()  
choices = [("Apple", "a"), ("Orange", "o"), ("Pear", "p")]
defaultChoice = "a"
userchoice = StringVar()
userchoice.set(defaultChoice)
def cancelAction(): userchoice.set("");master.quit()
Label(master, text="Choose a fruit:").pack()
for text, key in choices: 
  Radiobutton(master, text=text, variable=userchoice, value=key).pack(anchor=W)
Button(master, text="OK", command=master.quit).pack(side=LEFT, ipadx=10)
Button(master, text="Cancel", command=cancelAction).pack(side=RIGHT, ipadx=10)
mainloop()
if userchoice.get() <>"":
  print userchoice.get() # "a", or "o", or "p"
else:
  print "Choice canceled."

An alternative to radio button that immediately reacts to button press:

from Tkinter import *
import os
buttons = [("Users", r"C:\Users"),
           ("Windows", r"C:\Windows"),
           ("Program Files", r"C:\Program Files")]
master = Tk()
def open(filePath):
  def openInner():
    os.chdir(filePath) # Cross platform
    #os.system('start "" "'+filePath+'') # Windows
    master.quit()
  return openInner
Label(master, text="Choose a fruit:").pack()
for buttonLabel, filePath in buttons:
  Button(master, text=buttonLabel, command=open(filePath)).pack(anchor=W)
mainloop()

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List box[edit]

A list box can be used to create a simple multiple-choice dialog:

from Tkinter import *
master = Tk()  
choices = ["Apple", "Orange", "Pear"]
canceled = BooleanVar()
def cancelAction(): canceled.set(True); master.quit()
Label(master, text="Choose a fruit:").pack()
listbox = Listbox(master, selectmode=EXTENDED) # Multiple options can be chosen
for text in choices: 
  listbox.insert(END, text)
listbox.pack()    
Button(master, text="OK", command=master.quit).pack(side=LEFT, ipadx=10)
Button(master, text="Cancel", command=cancelAction).pack(side=RIGHT, ipadx=10)
mainloop()
if not canceled.get():
  print listbox.curselection() # A tuple of choice indices starting with 0
  # The above is a tuple even if selectmode=SINGLE
  if "0" in listbox.curselection(): print "Apple chosen."
  if "1" in listbox.curselection(): print "Orange chosen."
  if "2" in listbox.curselection(): print "Pear chosen."  
else:
  print "Choice canceled."

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Checkbox[edit]

Checkbox or check button can be created as follows:

from Tkinter import *
root = Tk()
checkbuttonState = IntVar()
Checkbutton(root, text="Recursive", variable=checkbuttonState).pack()
mainloop()
print checkbuttonState.get() # 1 = checked; 0 = unchecked

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Entry[edit]

Entry widget, a single-line text input field, can be used as follows:

from Tkinter import *
root = Tk()
Label(text="Enter your first name:").pack()
entryContent = StringVar()
Entry(root, textvariable=entryContent).pack()
mainloop()
print entryContent.get()

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Menu[edit]

Menus can be created as follows:

from Tkinter import *
root = Tk()
def mycommand(): print "Chosen."
menubar = Menu(root)

menu1 = Menu(menubar, tearoff=0)
menu1.add_command(label="New", command=mycommand)
menu1.add_command(label="Clone", command=mycommand)
menu1.add_separator()
menu1.add_command(label="Exit", command=root.quit)
menubar.add_cascade(label="Project", menu=menu1)
  
menu2 = Menu(menubar, tearoff=0)
menu2.add_command(label="Oval", command=mycommand)
menu2.add_command(label="Rectangle", command=mycommand)
menubar.add_cascade(label="Shapes", menu=menu2)

root.config(menu=menubar)

mainloop()

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LabelFrame[edit]

A frame around other elements can be created using LabelFrame widget as follows:

from Tkinter import *
root = Tk()
Label(text="Bus").pack()
frame = LabelFrame(root, text="Fruits") # text is optional
frame.pack()
Label(frame, text="Apple").pack()
Label(frame, text="Orange").pack()
mainloop()

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Message[edit]

Message is like Label but ready to wrap across multiple lines. An example:

from Tkinter import *
root = Tk()
Message(text="Lazy brown fox jumped. " * 5, width=100).pack() # width is optional
mainloop()

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Option menu[edit]

Drop-down list, in Tkinter option menu, can be created as follows:

from Tkinter import *
root = Tk()
options = ["Apple", "Orange", "Pear"]
selectedOption = StringVar()
selectedOption.set("Apple") # Default
OptionMenu(root, selectedOption, *options).pack()  
mainloop()
print selectedOption.get() # The text in the options list

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Text[edit]

Text widget is a more complex one, allowing editing of both plain and formatted text, including multiple fonts.

Example to be added.

Links:

Tcl/Tk version[edit]

The Windows installer for Python 2.3 ships with Tcl/Tk 8.4.3. You can find out about the version:

import Tkinter
print Tkinter.TclVersion # Up to 8.5
print Tkinter.TkVersion # Up to 8.5

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Related books[edit]

External links[edit]