The PHP-GTK Community site has posted two new code examples today - one dealing with the GtkProgressBar and the other with GtkFileSelection.
The first, about the progress bar widget, gives a simple one window example of making the workspace, the bar object and showing how to make it step through the progress (expanding).
The second example demonstrates using the GtkFileSelection widget to allow the user to select a file off of the local file system and pass the value back into the script.