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This chapter was rather short, because there really isn’t too much to the PHP-GTK installation process. You may have heard horror stories about people fighting with PHP-GTK for days before getting it to install right, but those stories are about PHP-GTK 1. With that version, installation was difficult at best. With PHP-GTK 2 those problems have largely been resolved and installation is much simpler. Installation of the dependencies and supporting packages is also pretty straightforward. Of course, there are a lot of configuration options you can set and plenty of customization, but not all of that is necessary to get a smooth-running PHP-GTK 2 installation. Now that everything is up and running, we can start looking at what makes PHP-GTK work the way it does. Chapter 3 describes the basic building blocks of PHP-GTK. You will learn about the base classes and how all of these classes interact with each other. Once you understand how the pieces of your application interact with each other, you can look at how they interact with the user.

PHP-GTK gives an application the ability to react to the user quickly and efficiently. The system of signals and events turns an unresponsive window on the screen into a functional and flexible application. Using the connect family of methods, user and system events emit signals that trigger callback methods that can then perform a designated task. When a signal is connected to a method, a signal handler is created. Signal handlers are the key to making an application respond to the user. Signal handlers can be created, blocked, unblocked, or destroyed, allowing for a constantly changing set of user-application interactions. Now that we have covered all of the basics, in the next chapter, you’ll start creating a real PHP-GTK application. Chapter 5 will focus on getting the Crisscott PIMS application off the ground. The chapter will start with creating a GtkWindow to hold the application. Next, we will look at setting some of the basic window properties and connections.

Multiline text is a powerful tool, not only for displaying large amounts of text, but also for collecting large amounts of data from the user. Using multiline text can be simple or rather complex. If plain black text is all you need, you can easily set up a GtkTextView with a buffer. If the text needs to be formatted or modified, GtkTextIter, GtkTextMark, and GtkTextTag allow that to happen. All of these widgets and objects make for a well-designed and specialized tool set. Text is not the only type of data that comes in large quantities. There are other types of large data sets, such as arrays and trees, that cannot be properly displayed with any of the tools seen so far. In Chapter 9, we will look at how to display large amounts of data. We will look at using trees and lists as the models behind several different ways to display data. Among the types of data that our sample application will display are a list of news headlines and a sortable and expandable list of products.

Trees and lists by themselves are relatively simple objects for modeling, rather than complex data structures. A tree or list can take a collection of data and make it easy to navigate and access individual elements. The organized nature of these models allows them to be used in a myriad of ways when combined with GtkTreeView and its associated objects. The specialization and abstraction of responsibility of these classes make for a very powerful tool set that can provide almost endless flexibility when it comes to how amodel should be displayed and accessed. Now that you have seen how to work with large collections of data, you’ll want to know how to display all of that data in a small space. Chapter 10 discusses how to make a section of an application scroll so that the user can access data that cannot fit in the space given for a tool. No longer will the sections of the application be restricted by the size of a container or the user’s screen. An endless amount of space will be made available for any piece of the application that needs it by providing scrollbars for both the horizontal and vertical axes.