[JAVA][Beginning Java 8 Games Development]

Chapter 6 ■ The Foundation of Game Design: The JavaFX Scene Graph and the InvinciBagel Game Infrastructure
JavaFX ImageView Class: Displaying Digital Images in a Design
The ImageView class is a public class that directly extends the javafx.scene.Node superclass, which is an extension
of the java.lang.Object (see Chapter 4). The ImageView object is therefore a type of Node object in the JavaFX Scene
Graph that is used for painting a view, using the data contained in an Image object. The class has methods that allow
image resampling (resizing), and, as with the Image class, you can lock the aspect ratio for scaling as well as specify
the resampling algorithm (smoothing quality).
The Java class hierarchy for the ImageView class starts with the java.lang.Object master class and uses this class
to create the javafx.scene.Node class, which is then employed to create an ImageView Node subclass. As Figure 6-4
illustrates (l. 10), like the Image class, ImageView is contained in the JavaFX image package. The ImageView class uses
the following Java class inheritance hierarchy structure:
java.lang.Object
> javafx.scene.Node
> javafx.scene.image.ImageView
The ImageView class provides three different (overloaded) ImageView() constructor methods. These range from
an empty constructor (which is the one you are going to use later on, in your code); to one that takes an Image object
as its parameter; to one that takes a URL String object as the parameter and creates the Image object automatically.
To create an ImageView object, the simple (empty) ImageView() constructor method uses the following format:
ImageView()
You will be employing this constructor method so that I can show you how to use the .setImage() method call to
load an Image object into an ImageView object. If you want to avoid using the .setImage() method call, you can use
the overloaded constructor method, which has the following format:
ImageView(Image image)
So, to set up an ImageView “explicitly” and wire it to the Image object looks like this:
splashScreenBackplate = new ImageView();
splashScreenBackplate.setImage(splashScreen);
// This uses the empty constructor method approach
You can condense this into one line of code, using an overloaded constructor method, structured as follows:
splashScreenBackplate = new ImageView(splashScreen); // using the overloaded constructor method
If you want to bypass the process of creating and loading an Image object, there is a constructor method for that
as well, which uses the following format:
ImageView(String url)
To load an image in the background (asynchronously), using its native (default) resolution and native aspect
ratio, the Image() constructor uses the following format:
splashScreen = new Image("/invincibagelsplash.png", 640, 400, true, false, true);
splashScreenBackplate = new ImageView();
splashScreenBackplate.setImage(splashScreen); // uses the empty constructor method approach
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