Object REXX GTK+ Dialog Manager

Package: GtkRxDlg

Version: 1.0.0

Authors: W. David Ashley dashley@us.ibm.com

This software is subject to the terms of the Common Public License. You must accept the terms of this license to use this software. Refer to CPLv1.0.htm for more information.

This package provides an interface from IBM Object REXX to the GTK+ libraries under Linux. You need some knowledge of the GTK+ APIs in order to fully utilize the GtkRxDlg package, but simple OREXX/GUI programs can be built by following the examples provided in the package.

This package is not a GTK+ API tutorial/reference.

Many people have contributed to this effort and I want to thank some of them here.

Table of Contents

What is GtkRxDlg

GtkRxDlg is NOT a complete GUI interface development environment for Object REXX. The main problem implementing a complete interface is that Object REXX does not support callback mechanisms. Callback support is necessary in order to create interactive responses to window events.

However, this does not mean that Object REXX cannot have a role to play in the development of GUI applications on Linux. The GTK+ toolkit allows the creation of dialogs which have builtin responses to events. GtkRxDlg allows the REXX programmer to build these dialogs, run them, and then query the values of the widgets in the dialog. This allows the Object REXX program to build and use a GUI interface to present and request data from the user thus providing a friendly face to the user.

In order to provide an easy API set to the Object REXX programmer all access to building and interacting with GTK+ widgets is done through a class library. The classes and methods in the class library wrap the REXX external function APIs to the GTK+ libraries providing a level of abstraction to those functions.

Building GUIs with the GtkRxDlg Object REXX classes is really easy and only a minimal knowledge of the GTK+ library is needed. The examples provided with this package should provide enough information for you to build simple Object REXX GUI applications quickly.

Have fun!

Linux Requirements Information

The following are the installation requirements for the GtkRxDlg package.

• A Linux system with IBM Object REXX installed.
• A Linux system with the GTK+ 2.x libraries installed.

If you do not have IBM Object REXX installed you can obtain it for free (as in free beer) from IBM here. This site provides you with a fully working, non-expiring, evaluation copy of Object REXX.

Linux Package Installation

To install the package on Linux, extract the contents into a subdirectory of your choice. I suggest it be placed into /opt (you may need to be logged on as root to install it in /opt). Log on as root and run the install.rex script from the gtkrxdlg subdirectory.

Linux Information

The GtkRxDlg external function shared library was compiled under Fedora Core 1 Linux using the standard GCC compiler installed from Fedora Core 1. You may need to compile your own module for your version of GCC, GTK+ and Linux.

The package was tested using

• Object REXX for Linux version 2.3.3
• Red Hat Linux version 9 and Fedora Core 1.

All the source files (except makefile.win) are in Unix format (lines are delimited only by a line feed).

Windows Information

Currently the the Windows library is experimental and is not verfied or tested. There is no support for the Windows version of the library.

Known Problems and Restrictions

1. Only IBM Object REXX is supported.
2. GTK+ callbacks to Object REXX are not supported.
3. Not all GTK+ widgets are supported.
4. The Windows version of the library is not verified or tested.

Future Enhancements

None at this time. But if you have suggestions please contact me.