Let's go take a look at these files now.  If there are any I don't cover today, we'll be going over them in a future article.

fbx_Circuits.php

Included by fbx_Fusebox3.0_PHP4.1.x.php (see below), fbx_Circuits.php is where the circuits of our Fusebox are defined.  This is the place where values are set that determine the structure of the app.  A typical fbx_Circuits (and the one you downloaded) looks like this:

<?

$Fusebox["circuits"]["home"] = "home";

?>

Don't worry - we'll be adding circuits to this code soon enough.

fbx_Fusebox3.0_PHP4.1.x.php (or fbx_Fusebox3.0_PHP4.0.6.php)

This is the "engine" of the Fusebox application - the file that makes it all possible.  It does the following things:

1. Includes fbx_Circuits.php, where the circuits array is populated with your application's circuit definitions.  The circuit definitions in fbx_Circuits.php map your site's folder structure to a central circuits structure.

2. Creates a reverse-lookup of the directory structure you defined in fbx_Circuits.php.

3. Includes fbx_Settings.php, where default values are set for your application.

4. Receives the fuseaction and circuit variables, which control what content is displayed in your application.

5. Executes the fuseaction in the correct circuit's fbx_Switch file.

6. Includes fbx_Layouts.php, where you can customize the look and feel of your application.

You'll be happy to know that this file should not be modified in any way, and can function as the heart of your web application right out of the box, so to speak.  You should understand the full functionality behind this key file, but this is by no means required since editing the file's source code could make your application incompliant with the Fusebox 3 specification, defeating the whole purpose of using the methodology in the first place!

fbx_Switch.php

This file consists of a switch/case statement that tells the application which files to include.  Here's the code you see when you open it up:

switch($Fusebox["fuseaction"]) {

      case "main":

      case "Fusebox.defaultFuseaction":

            include("dsp_main.php");

            break;

      default:

            print "I received a fuseaction called <b>'" . $Fusebox["fuseaction"] . "'</b> that circuit <b>'" . $Fusebox["circuit"] . "'</b> does not have a handler for.";

            break;

}

Leave this file alone for now.  We'll be back to it shortly.

fbx_Settings.php

This is where default values are set for each circuit.  Circuits (subdirectories) each have their own versions of this file.  If they do, the variables' values in the individual circuits' fbx_Settings.php files will overwrite their default values in the root directory's fbx_Settings.php. 

index.php - or whatever your server's default document is called.

This is where we load the core file, or for lack of a better word engine, of the Fusebox architecture: fbx_Fusebox3.0_PHP4.1.x.php.  We'll be linking back to this file for every page request and passing it a variable called a fuseaction.  The fuseaction will give the engine the information it needs to display the circuit's content.  Note: this file can be renamed to whatever your web server uses as its default document.

DefaultLayout.php

This is a typical layout file, and is required in each circuit of your application.  If you were making an application with many circuits, you'd want to make sure this file is placed in each circuit's directory, along with the other core files required in each circuit.  In a future article we'll discuss the incredibly cool use of nested layouts, which are another example of the versatility and scalability of Fusebox-based architecting.

fbx_Layouts.php

You should have at least one fbx_layouts.php in your application, depending on which circuits require unique layouts.  This file controls the layout of each circuit or $Fusebox["layoutFile"] element.  Any circuit that has its own layout requirements should have its own fbx_Layouts.php file in its root directory.  If not, fbx_Layouts.php can be omitted and the application root's fbx_Layouts.php will take over.  Fusebox enables you to "nest" these layouts in a powerful way, but that topic is best left for another time.

dsp_main.php

A typical display file.  This file will be included in our main circuit.