Python provides various options for developing graphical user interfaces (GUIs). Most important are listed below.

• Tkinter − Tkinter is the Python interface to the Tk GUI toolkit shipped with Python. We would look this option in this chapter.

• wxPython − This is an open-source Python interface for wxWindows http://wxpython.org.

• JPython − JPython is a Python port for Java which gives Python scripts seamless access to Java class libraries on the local machine http://www.jython.org.

There are many other interfaces available, which you can find them on the net.

Tkinter Programming

Tkinter is the standard GUI library for Python. Python when combined with Tkinter provides a fast and easy way to create GUI applications. Tkinter provides a powerful object-oriented interface to the Tk GUI toolkit.

Creating a GUI application using Tkinter is an easy task. All you need to do is perform the following steps −

• Import the Tkinter module.

• Create the GUI application main window.

• Add one or more of the above-mentioned widgets to the GUI application.

• Enter the main event loop to take action against each event triggered by the user.

Example

#!/usr/bin/python

import Tkinter
top = Tkinter.Tk()
# Code to add widgets will go here...
top.mainloop()

This would create a following window −

Tkinter Widgets

Tkinter provides various controls, such as buttons, labels and text boxes used in a GUI application. These controls are commonly called widgets.

There are currently 15 types of widgets in Tkinter. We present these widgets as well as a brief description in the following table −

Let us study these widgets in detail −

Standard attributes

Let us take a look at how some of their common attributes.such as sizes, colors and fonts are specified.

• Dimensions

• Colors

• Fonts

• Anchors

• Relief styles

• Bitmaps

• Cursors

Let us study them briefly −

Geometry Management

All Tkinter widgets have access to specific geometry management methods, which have the purpose of organizing widgets throughout the parent widget area. Tkinter exposes the following geometry manager classes: pack, grid, and place.

• The pack() Method − This geometry manager organizes widgets in blocks before placing them in the parent widget.

• The grid() Method − This geometry manager organizes widgets in a table-like structure in the parent widget.

• The place() Method − This geometry manager organizes widgets by placing them in a specific position in the parent widget.

Let us study the geometry management methods briefly −