Unknown size of TextFields Array JavaFX

Question

I am trying to build a GUI stack using JavaFX. I am supposed to ask the user how many elements he wants for the stack. Then the number of text fields should appear on the right screen (based on the size of user's entry). I have been trying all day in vain.

Here is what I have been trying to do so far. Once I solve TextFields array issue, I should complete my program.

public class StackGUI extends Application {
    private Button push, pop, peek, empty, create, build;
    private TextField[] data;
    private TextField size, numberText;
    private Label sizeLabel, numberLabel;
    private int sizeOfStack;

    String sizeDialog = "0";
    
    @Override
    public void start(Stage primaryStage) {
        BorderPane border = new BorderPane();
        
        // Buttons
        push = new Button("PUSH");
        push.setPrefSize(150, 50);

        pop = new Button("POP");
        pop.setPrefSize(150, 50);

        peek = new Button("PEEK");
        peek.setPrefSize(150, 50);

        empty = new Button("EMPTY");
        empty.setPrefSize(150, 50);

        FlowPane bottom = new FlowPane();
        bottom.setHgap(10);
        bottom.setAlignment(Pos.CENTER);
        bottom.getChildren().addAll(push, pop, peek, empty);

        border.setBottom(bottom);
        
        //Center
        VBox center = new VBox(5);
        center.setAlignment(Pos.CENTER);

        size = new TextField();
        size.setMaxWidth(200);
        size.setEditable(false);

        numberLabel = new Label("Enter a number: ");
        numberText = new TextField();
        numberText.setMaxWidth(200);
        //sizeLabel = new Label("How many numbers? ");

        create = new Button("Create a stack");
        create.setPrefWidth(200);

        build = new Button("Build the stack");
        build.setPrefWidth(200);
        build.setDisable(true);

        center.getChildren().addAll(create, size, build);

        border.setCenter(center);
        
        //Stack TextFields --> right
         
        create.setOnAction(ae -> {
            TextInputDialog input = new TextInputDialog();
            input.setContentText("How many Numbers");
            input.setHeaderText("Size Of Stack");
            input.setTitle("Stack");
            input.showAndWait();

            size.setAlignment(Pos.CENTER);
            size.setText("Number Of Elements: " + input.getEditor().getText());

            sizeDialog = input.getEditor().getText();

            build.setDisable(false);
        });
        
        sizeOfStack = Integer.parseInt(sizeDialog);
        data = new TextField[sizeOfStack];
        HBox right = new HBox(5);
        build.setOnAction(ae -> {
            create.setDisable(true);
            numberText.setPromptText("Enter a number to push");
            center.getChildren().addAll(numberLabel, numberText);
            for (int i = 0; i < sizeOfStack; i++) {
                data[i] = new TextField();
                right.getChildren().add(data[i]);
            }
        });

        border.setRight(right);
        
        //Scene
        Scene scene = new Scene(border, 800, 400);
        primaryStage.setScene(scene);
        primaryStage.setTitle("Stack");
        primaryStage.show();
    }

    public static void main(String[] args) {
        launch(args); 
    }
}

Answer 1

As @James_D pointed out, you need to move sizeOfStack = Integer.parseInt(sizeDialog); inside of build.setOnAction. You also need to move data = new TextField[sizeOfStack] ;.

I also moved HBox right = new HBox(sizeOfStack); and border.setRight(right);, but that may not have been necesary.

Code:

build.setOnAction((ActionEvent event) - > {
    sizeOfStack = Integer.parseInt(sizeDialog);
    data = new TextField[sizeOfStack];

    create.setDisable(true);
    numberText.setPromptText("Enter a number to push");
    center.getChildren().addAll(numberLabel, numberText);

    HBox right = new HBox(sizeOfStack);
    for (int i = 0; i < sizeOfStack; i++) {
        TextField text = new TextField();
        data[i] = text;
        right.getChildren().add(data[i]);
    }
    border.setRight(right);
});