Coding the PongGame class
The first thing we will do is solve the problem of our PongGame class not being of the View type. Update the class declaration as highlighted, like this:
class PongGame extends SurfaceView {
You will need to import the android.view.SurfaceView class as shown next so that Android Studio knows about the SurfaceView class. You can add the line of code after the package declaration in the PongGame.java file or use the Alt + Enter keyboard combination as we have done before.
SurfaceView is a descendant of View and now PongGame is, by inheritance, also a type of View. Look again at the import statement that has been added. This relationship is made clear as highlighted next:
android.view.SurfaceView
Tip
Remember that it is because of polymorphism that we can send descendants of View to the setContentView method in the PongActivity class and it is because of inheritance that PongGame is a type of SurfaceView.
There are quite a few descendants...
