Book Image

Tcl/Tk 8.5 Programming Cookbook

Book Image

Tcl/Tk 8.5 Programming Cookbook

Overview of this book

With Tcl/Tk, you can create full-featured cross-platform applications in a simple and easy-to-understand way without any expensive development package; the only tools required are a simple text editor and your imagination. This practical cookbook will help you to efficiently interact with editors, debuggers, and shell type interactive programs using Tcl/Tk 8. This cookbook will comprehensively guide you through practical implementation of Tcl/Tk 8.5 commands and tools. This book will take you through all the steps needed to become a productive programmer in Tcl/Tk 8. Right from guiding you through the basics to creating a stand-alone application, it provides complete explanation of all the steps along with handy tips and tricks. The book begins with an introduction to the Tcl shell, syntax, variables, and programming best practices in the language. It then explores procedures and the flow of events with control constructs followed by advanced error trapping and recovery. From Chapter 4, a detailed study of string expressions and handling enables you to handle various string functions and use lists to expand the string functionality. The book then discusses in-depth the Tcl Dictionary and how to utilize it to store and retrieve data. File operations and Tk GUI handling are covered extensively along with a developing a real-world address book application to practice the concepts learned.
Table of Contents (20 chapters)
Tcl/Tk 8.5 Programming Cookbook
About the Author
About the Reviewers

Controlling layout with the grid command

Care must be taken in packing the widgets to ensure that the desired layout is obtained. The pack command provides a convenient method of geometry management for simple forms. However, for more complex forms, the grid command allows you to manage your widget placement by creating and configuring rows and columns for widget placement.

To illustrate this better, think of the grid as being similar to a table or a spreadsheet, as it contains rows and columns, as follows:


Column 0

Column 1

Column 2

Row 0


Row 1


Row 2


Please note that the column and row numbering are zero-based. This is the grid layout that we will use in the following example.

Based on the options provided, when invoked, the grid command assumes several forms. The syntactical options are as follows:



grid widget row column

Behaves in the same manner as grid configure.

grid anchor parent anchor

Controls placement of the grid itself. Acceptable...