GUI programming has always been of my interests, and I found that Gtk+ is a very nice toolkit, except that programming with it in C is somewhat tedious. After witnessing PyGtk and GTK-Perl implementations, I decided to see if PHP could be made to interface with Gtk+, even minimally. Starting in August of 2000, I began to have a bit more free time so that is when I started experimenting. My main guideline was the PyGtk implementation as it was fairly feature complete and had a nice object-oriented interface. James Henstridge, the author of PyGtk, provided very helpful advice during those initial stages.
Hand-writing the interfaces to all the Gtk+ functions was out of the question, so I seized upon the idea of code-generator, similar to how PyGtk did it. The code generator is a PHP program that reads a set of .defs file containing the Gtk+ classes, constants, and methods information and generates C code that interfaces PHP with them. What cannot be generated automatically can be written by hand in .overrides file.
Working on the code generator and the infrastructure took some time, because I could spend little time on PHP-GTK during the fall of 2000. After I showed PHP-GTK to Frank Kromann, he got interested and started helping me out with code generator work and Win32 implementation. When we wrote the first Hello World program and fired it up, it was extremely exciting. It took a couple more months to get the project to a presentable condition and the initial version was released on March 1, 2001. The story promptly hit SlashDot.
Sensing that PHP-GTK might be extensive, I set up separate mailing lists and CVS repositories for it, as well as the gtk.php.net website with the help of Colin Viebrock. The documentation would also need to be done and James Moore came in to help with that.
Since its release PHP-GTK has been gaining popularity. We have our own documentation team, the manual keeps improving, people start writing extensions for PHP-GTK, and more and more exciting applications with it.