JavaFX :: Slot Machine In Netbeans - Scene / Stage

I want to create a slot machine in NetBeans, with JavaFX library (without using JavaFX Scene Builder) but i have some problems to create UI.

I created algorithm already but without visuals.

Now my code is:
 
public class BEST extends Application {
private ImageView var; //init imageview of images
public static void main(String[] args) {
launch(args);
 
[Code] ....

createbottom(); and creategr(); i wrote already (and my program creates grid pane of random images with double dimension array, random and imageview) and program runs, but i don t know how to keep track of credits balance,in the same time to create new random gridpane of images and to get rid of every gridpane.

Here is creategr();
 
private GridPane creategr(){
final GridPane creategr = new GridPane();
int[][] newarray=new int[3][3];
int w=100;
for(int i=0; i<3; i++){
for(int j=0; j<3;j++)

[Code] ....

Button "SPIN" is created in createbottom();.