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How to set an action to occur on pressing of any keyboard key in JavaFX?

So I want to do a title Menu for a video game project for college. I want to display a message press any key to continue... then when the user pressed any key, including the mouse, a method would run to set the stage to the next menu.
I posted all the relevant code bellow but short version is:
BackgroundImangeDisplayPane extends display pane and adds a background image.
TitleCard extends BackgroundImangeDisplayPane adds a VBox and 2 labels to the VBox
I'm using public void start(Stage primaryStage) throws Exception as the main, I set the setOnActionxxx methods here
I have tried using the set on action method on root and Vbox and non of them work... when I click nothing happens... But when I resize the window The root.setOnActionXXX "activates".
If I write the setOnAction methods on the TitleCard class It kind of works but then I cant switch the stage.
I will post the code bellow as well an explanation of the Scene structure its not to complicated:
// this will be the borderpane for every scene it recives a backgund
//images that will be present in every menu
public BackgroundImangeDisplayPane() {
try {
stream = new FileInputStream(imagePath.toString());
Image image = new Image(stream);
ImageView imageView = new ImageView();
imageView.setImage(image);
imageView.setFitWidth(1920);
imageView.setPreserveRatio(true);
this.getChildren().add(imageView);
BackgroundSize backgoundSize = new BackgroundSize(AUTO, AUTO, true, true, true, true);
BackgroundImage backgroundImage = new BackgroundImage(image, NO_REPEAT, NO_REPEAT, CENTER, backgoundSize);
Background background = new Background(backgroundImage);
this.setBackground(background);
} catch (Exception e) {
}
}
//This extends `BackgroundImangeDisplayPane` and places on top of it a A Vbox with two lables: the title and "press any key to continue..."
// it then adds styles to the labels
public class TitleCard extends BackgroundImangeDisplayPane {
Label title = new Label("Boats & Docks"); // lable 1
Label subtitle = new Label("Press any key to continue ..."); label2
public TitleCard(){
super();
VBox vbox = new VBox();
vbox.getChildren().add(title);
vbox.getChildren().add(subtitle);
this.setCenter(vbox);
this.setAlignment(vbox, Pos.CENTER);
vbox.setAlignment(Pos.CENTER);
title.setFont(new Font(170)); // set to Label
title.setTextFill(Color.SNOW);
title.setEffect(new DropShadow());
subtitle.setFont( new Font (30));
}
}
...
//Works as the "main" in javaFX
private Stage primaryStage;
#Override
public void start(Stage primaryStage) throws Exception {
TitleCard root = new TitleCard();
/*BasicMenu menu = new BasicMenu(5);
menu.ButtonSetOnAction(0, e -> changeScene() );
BackgroundImangeWithCustomMenu background = new
BackgroundImangeWithCustomMenu(menu,50,50);
root.setCenter(background);*/
Button b = new Button();
b.setOnAction(e -> changeSceneToLoginMenu());
System.out.println(root.getChildren().get(1).getClass());
root.getChildren().get(1).setFocusTraversable(true);
root.getChildren().get(1).setOnMouseClicked(e -> changeSceneToLoginMenu());
root.getChildren().get(1).setOnKeyPressed(e -> changeSceneToLoginMenu());
root.getChildren().get(0).setOnMouseClicked(e -> changeSceneToLoginMenu());
root.getChildren().get(0).setOnKeyPressed(e -> changeSceneToLoginMenu());
/*
root.setOnMouseClicked(e -> changeSceneToLoginMenu());
root.setOnKeyReleased(e -> changeSceneToLoginMenu());
root.setOnKeyPressed(e -> changeSceneToLoginMenu());
*/
Scene scene = new Scene(root, 1280, 720);
primaryStage.setScene(scene);
primaryStage.show();
this.primaryStage = primaryStage;
}

As proposed by James in comments, when a key is pressed on the scene, navigate to the next scene (or replace the root in the current scene, and remove the key press handler).
scene.setOnKeyPressed(e -> navigateToNextScene());

I managed to find a very simple working solution but I don't fully undestand why it does work. I Noticed that if I set the handler in the same class the node was instanciated the handler would work fine But if I tried to get the node with a method to the main fuction via root.getChildren().get(1) and then cast it to the VBox element the handler would not work.
As a solution I made the VBox a field and wrote a setter method for the VBox event Handler in the TitleCard Class. This fixed the problem.
I marked the code added as solution code with comments
public class TitleCard extends BackgroundImangeDisplayPane {
Label title = new Label("Boats & Docks"); // lable 1
Label subtitle = new Label("Press any key to continue ..."); label2
VBox vbox = new VBox; // solution code
public TitleCard(){
super();
VBox vbox = new VBox();
vbox.getChildren().add(title);
vbox.getChildren().add(subtitle);
this.setCenter(vbox);
this.setAlignment(vbox, Pos.CENTER);
vbox.setAlignment(Pos.CENTER);
title.setFont(new Font(170)); // set to Label
title.setTextFill(Color.SNOW);
title.setEffect(new DropShadow());
subtitle.setFont( new Font (30));
}
// Solution Code
public void setVBoxHandler(EventHandler<? super MouseEvent> value){
vbox.setOnMouseClicked(value);
}
}
Then I set the handler in the start method:
public void start(Stage primaryStage) throws Exception {
TitleCard root = new TitleCard();
VBox vBox =(VBox) root.getChildren().get(1);
root.setVBoxHandler(e->changeSceneToLoginMenu() ); // solution Code
Scene scene = new Scene(root, 1280, 720);
primaryStage.setScene(scene);
primaryStage.show();
this.primaryStage = primaryStage;
}
public void changeSceneToLoginMenu() {
System.out.println("It finally worked");
Scene currentScene = new Scene(new Group(),100,100); // just a demo
primaryStage.setScene(currentScene);
}
notes: The type of value on the method setVBoxHandler(EventHandler<? super MouseEvent> value) will depend on the setOnXXX method used. For example I tested and this soultion also works for buttons just need to change the type to EventHandler<ActionEvent> value.
Some coments on the question posted links on "how to use handlers", this posts used anomimous classes. I belived This way is outdated. I used lambdas in the code the end result is the same but more redable code
Just for reference if future readers are using anomimous classes the solution would be the same just change the way you set up the handler:
// lambdas
setVBoxHandler( e -> System.out.println("Code run if mouse is clicked "));
// anomimous classes
setVBoxHandler(new EventHandler<ActionEvent>() {
#Override
public void handle(ActionEvent event){
System.out.println("Code run if mouse is clicked ");
}
});

JavaFX - How to change scene using a scene from another class?

I have the following class which has a button.
public class GUI extends Application {
private BorderPane mainLayout = new BorderPane();
#Override
public void start(Stage primaryStage) {
primaryStage.setTitle("Main Menu");
FlowPane layout = new FlowPane();
Button button = new Button("Click");
layout.getChildren().addAll(button);
mainLayout.setTop(layout);
Scene scene = new Scene(mainLayout, 600, 600);
primaryStage.setScene(scene);
primaryStage.show();
}
}
If I have another class with a scene, how can I update the GUI class to show the scene by pressing the button?

The preferred mechanism would probably be to get the stage dynamically from a trigger event, for example:
button.setOnAction(event -> {
Scene newScene = // ... commands which define the new scene.
Stage stage = ((Node) event.getTarget()).getScene().getStage();
// or alternatively, just:
// Stage stage = button.getScene().getStage();
stage.setScene(newScene);
});
An alternative is to provide a static accessor to the main stage in the Application.
Change your GUI class to add an accessor for the stage:
public class GUI extends Application {
private static Stage guiStage;
public static Stage getStage() {
return guiStage;
}
#Override
public void start(Stage primaryStage) {
guiStage = primaryStage;
// other app initialization logic . . .
}
}
In your class which needs to change the scene for the GUI stage to a new scene, invoke:
Scene newScene = // ... commands which define the new scene.
GUI.getStage().setScene(newScene);
Using a static accessor in this specific instance is generally OK, because you can only have a single Application instance launched for a given JVM execution. The only real drawback is that you have a coded dependency between the class creating your new scene and your Application class. But, for some application types, this won't matter.

JavaFX : Getting back to main page without FXML

I am learning JavaFx on my own and have not reached FXML yet. I am stuck at one application where I plan to have it go back to the main scene of the Application after the user enters their credentials on a second scene. I managed to bring up the second scene from the main one but I could not get from the second scene to the main one. I tried getting the main scene and pane using a getter but no luck. Can you guys teach the right way?
Thank you in advance.
public class Landing extends Application {
BorderPane bp;
Scene scene;
#Override
public void start(Stage primaryStage) throws Exception {
primaryStage.setTitle("Welcome to our Telco!");
bp = new BorderPane();
VBox vbox = new VBox();
Button login = new Button("Login");
login.setMinWidth(100);
Button acc = new Button("Account Information");
acc.setMinWidth(100);
vbox.getChildren().addAll(acc);
bp.setCenter(vbox);
acc.setOnAction(e ->{
AccountInfo account = new AccountInfo();
primaryStage.setTitle("Account Information"); // Set the stage title
primaryStage.getScene().setRoot(account.getbp());; // Place the scene in the stage
});
scene = new Scene(bp, 750, 550);
primaryStage.setScene(scene);
primaryStage.show();
}
public Pane getbp() {
return bp;
}
public Scene getSc(){
return scene;
}
the button to get the main scene
public class AccountInfo {
BorderPane pane;
Landing main = new Landing();
Scene scene;
AccountInfo() {
Button c = (new Button("Back"));
c.setStyle("-fx-background-color: pink");
c.setOnAction((ActionEvent e) -> {
main.getbp();
main.getSc();
});
public Pane getbp() {
return pane;
}
}

Landing is not a scene, it is an Application. So far from what you've shown, there is only one scene in your whole application. You must never try to instantiate (and subsequently run) more than one instance of any Application class within the same JavaFX application lifetime. You are dangerously going towards this direction when you do Landing main = new Landing(); in your AccountInfo class.
From Javadoc for Application.launch:
Throws: IllegalStateException - if this method is called more than
once.
What you need is to have the first scene for login (i.e. enter credentials). When login is successful, you create a new scene object and populate that scene with your next "view", then set that new scene to the stage.
public class Landing extends Application {
BorderPane bp;
Scene scene;
#Override
public void start(Stage primaryStage) throws Exception {
primaryStage.setTitle("Welcome to our Telco!");
bp = new BorderPane();
VBox vbox = new VBox();
Button login = new Button("Login");
login.setMinWidth(100);
Button acc = new Button("Account Information");
acc.setMinWidth(100);
vbox.getChildren().addAll(acc);
bp.setCenter(vbox);
acc.setOnAction(e -> {
primaryStage.setTitle("Account Information"); // Set the stage title
BorderPane infoScenePane = new BorderPane();
Scene infoScene = new Scene(infoScenePane);
primaryStage.setScene(infoScene);
});
scene = new Scene(bp, 750, 550);
primaryStage.setScene(scene);
primaryStage.show();
}
}

JavaFx: How to keep the window maximizing?

My app, if I click the "maximize button", it will maximize the window. But if I go to another scene(in the same stage), the window will restore to the original size. So, how can I control it to keep maximizing?

I used primaryStage.setMaximized(true); after calling show(); method in Java 8 implementation. It keeps other scenes maximizing.

I had the same problem. I fixed it creating a root stage with that only contains a menu bar and a tool bar, like this:
I initialized this window in the start method with:
FXMLLoader loader = new FXMLLoader();
loader.setLocation(Main.class.getResource("view/RootLayout.fxml"));
rootLayout = (BorderPane) loader.load();
RootController controller= loader.getController();
// Show the scene containing the root layout.
Scene scene = new Scene(rootLayout);
primaryStage.setScene(scene);
primaryStage.show();
Later, when you want to load a FXML file or scene into the root container, you could make it with the next lines in another method:
FXMLLoader loader = new FXMLLoader();
loader.setLocation(Main.class.getResource("view/principal.fxml"));
AnchorPane principalOverview = (AnchorPane) loader.load();
// Set person overview into the center of root layout.
rootLayout.setCenter(principalOverview);
// Get the controller instance
controllerPrincipal = loader.getController();
in that way every scene you add to the root stage will get the size of the root.

This is how I did it:
#FXML
private Button goBtn;
Stage stage = (Stage) goBtn.getScene().getWindow();
Scene scene = goBtn.getScene();
try {
FXMLLoader loader = new FXMLLoader(getClass().getResource("Activity.fxml"));
scene.setRoot(loader.load());
stage.setScene(scene);
stage.show();
} catch (IOException e) {
e.printStackTrace();
}

JavaFX Anchor Constraints

I have an FXML file which has a split pane and 2 rectangles in it. I have both rectangles anchored properly via the FXML but from the code I am generating new rectangles but I can't seem to get the constraints on them working, I set them to the same settings as the rectangles in the FXML(constraint wise) but nothing. I think the issue is the rectangles in the FXML are inside a Split Pane where as the ones generated from the Java code are in the Main AnchorPane. Here is the code any ideas?
public void start(Stage stage) throws Exception {
//GridPane root = new GridPane();
AnchorPane root = fxmlLoader.load(getClass().getClassLoader().getResource("fxml/TestConveyorView.fxml")).getRoot();
Box box = new Box(1);
Rectangle rect = new Rectangle(50,50, box.getStatus().getColor());
rect.setX(385.0);
AnchorPane.setLeftAnchor(rect, 385.0);
AnchorPane.setRightAnchor(rect, 294.0);
root.getChildren().addAll(rect);
Scene scene = new Scene(root);
// BackgroundImage background = new BackgroundImage(null, BackgroundRepeat.REPEAT, BackgroundRepeat.REPEAT, BackgroundPosition.DEFAULT, BackgroundSize.DEFAULT);
stage.setScene(scene);
stage.show();
}

Fixed by removing all the extra code in the main class like below.
public void start(Stage stage) throws Exception {
AnchorPane root = fxmlLoader.load(getClass().getClassLoader().getResource("fxml/TestConveyorView.fxml")).getRoot();
Scene scene = new Scene(root);
// BackgroundImage background = new BackgroundImage(null, BackgroundRepeat.REPEAT, BackgroundRepeat.REPEAT, BackgroundPosition.DEFAULT, BackgroundSize.DEFAULT);
stage.setScene(scene);
stage.show();
}
And adding these to things to my controller
#FXML
AnchorPane Splitright;
Splitright.getChildren().add(rectangle);
As it turns out the shapes were just being thrown on top of everything not actually being placed in the proper AnchorPane, which is what I suspected was happening.