[JAVA][Beginning Java 8 Games Development]

Chapter 9 ■ Controlling Your Action Figure: Implementing Java Event Handlers and Using Lambda Expressions
Finishing the UI Design: Coding a Game Play Button
The next thing that we will need to do is to finish the Button control event handling code so that when we click on
the GAME PLAY Button object, the white background is revealed for us to develop our game over. Later on we can
use the ImageView plates that we use for our splash screen support to provide background image compositing
for the game to make it more interesting visually. The way that we are going to hide the two ImageView Node
objects in the Scene Graph is by calling the .setVisible() method off of each of these objects inside of the
.handle() method that is attached to the PLAY GAME UI Button object. This can be seen in the bottom portion
of Figure 9-2, and would be implemented using the following two lines of Java code, inside of the .handle()
EventHandler method structure:
splashScreenBackplate.setVisible(false);
splashScreenTextArea.setVisible(false);
Figure 9-2. Use a .setVisible() method for the ImageView class to hide background image plates and reveal White color
As you can see, there is also a wavy yellow warning highlight under the EventHandler part of
this event handling structure which relates to Java lambda expressions. After we finish implementing all of the
final UI design code for the Buttons that controls what is visible to the player, and which imagery it is showing
them, I will get into lambda expressions, and we will get rid of these warning messages in your code as well.
After that, we’ll move on to implement arrow key event handling structures, so that the user can navigate the
InvinciBagel around the screen.
First, let’s test the code that we put into the previously empty PLAY GAME Button event handling structure.
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