[JAVA][Beginning Java 8 Games Development]

Chapter 6 ■ The Foundation of Game Design: The JavaFX Scene Graph and the InvinciBagel Game Infrastructure
Scene Graph Design: Streamlining the Existing .start() Method
Now, you can optimize the .start() method so that it only has one or two dozen lines of code. First, modularize the
Scene Graph node creation Java routines into their own createSplashScreenNodes() method, which will be called
at the top of the .start() method, as can be seen in Figure 6-5. After all the nodes are created in this method, create an
addNodesToStackPane() method to add the nodes to the StackPane root node, and then have the three primaryStage
lines of code configuring and managing the Stage object and, finally, the ActionEvent handling code routines that
“wire” the Button UI controls to the Java code to be executed when they are clicked.
Figure 6-5. Organize the .start() method with the createSplashScreenNodes() and addNodesToStackPane() methods
As you can see, after you duplicate the .setOnAction() constructs for each Button object, when you collapse
the EventHandler routines, you have nine lines of code: one for creating nodes, one for adding nodes to root, three
for Stage object setup, and four for UI Button event-handling. This is pretty compact, if you consider the amount
of functionality you are adding to the top level of your game structure (game play, instructions, legal, credits,
scoreboard).
It is important that you do things in the correct order, as some Java code is predicated on other Java code. For this
reason, the object declarations come first; then, inside the .start() method, you create (instantiate) the nodes. Once
these are declared, named, and instantiated (created), you add them to the StackPane root node and then configure
(using the .setTitle() method) and add the scene Scene object to the primaryStage Stage object, using the .setScene()
method. After your objects are in system memory, only then will you be able to process ActionEvent handling
routines, which are attached to your four Button UI controls. Next, let’s make sure that your digital image assets, which
will be referenced in the createSplashScreenNodes() method, are in the proper NetBeans folder.
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