I have a pet project which is a 2D game engine.
After creating all the backend functionality, I want to implement a UI for it.
My current plan is to do this via MVC because it strikes me as the most feasible way of doing this (logic first, then UI).
Now, I am unsure how to design/implement this with either Swing or JavaFX, as I do not yet fully understand what the underlying concepts of either are.
Can someone describe to me how to implement MVC with Swing or JavaFX?
You can have a model that is a general one can be used by different views.
To demonstrate it let's first introduce a interface that can be used to listen to such model:
//Interface implemented by SwingView and used by Model
interface Observer {
void observableChanged();
}
Consider a very simple model, with one attribute only: an integer value between 0 and a certain max:
//Generic model. Not dependent on the GUI tool kit. Use by Swing as well as JAvaFX
class Model {
private int value;
private static final int MAX_VALUE = 100;
private Observer observer;
int getValue(){
return value;
}
void setValue(int value){
this.value = Math.min(MAX_VALUE, Math.abs(value));
notifyObserver();
}
int getMaxValue() {
return MAX_VALUE;
}
//-- handle observers
void setObserver(Observer observer) {
this.observer = observer;
}
private void notifyObserver() {
if(observer != null) {
observer.observableChanged();
}
}
}
Note that the model calls observer.observableChanged() when value changes it.
Now let's use this model with a Swing gui that displays a random number :
import java.awt.*;
import java.util.Random;
import javax.swing.*;
//Swing app, using a generic model
public class SwingMVC {
public static void main(String[] args) {
new SwingController();
}
}
//SwingController of the MVC pattern."wires" model and view (and in this case also worker)
class SwingController{
public SwingController() {
Model model = new Model();
SwingView swingView = new SwingView(model);
model.setObserver(swingView); //register view as an observer to model
update(model);
}
//change model
private void update(Model model) {
Random rnd = new Random();
//use swing timer so the change is performed on the Event Dispatch Thread
new Timer(1000,(e)-> model.setValue(1+rnd.nextInt(model.getMaxValue()))).start();
}
}
//view of the MVC pattern. Implements observer to respond to model changes
class SwingView implements Observer{
private final Model model;
private final JLabel label;
public SwingView(Model model) {
this.model = model;
JFrame frame = new JFrame();
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.setLocationByPlatform(true);
frame.setLayout(new GridBagLayout());
label = new JLabel(" - ");
label.setFont(new Font(label.getFont().getName(), Font.PLAIN, 48));
label.setHorizontalTextPosition(SwingConstants.CENTER);
frame.add(label);
frame.pack();
frame.setVisible(true);
}
#Override
public void observableChanged() {
//update text in response to change in model
label.setText(String.format("%d",model.getValue()));
}
}
We can use the very same model and achieve the same functionality with a JavaFx gui:
import java.util.Random;
import javafx.animation.PauseTransition;
import javafx.application.Application;
import javafx.scene.Parent;
import javafx.scene.Scene;
import javafx.scene.control.Label;
import javafx.scene.layout.StackPane;
import javafx.scene.text.Font;
import javafx.stage.Stage;
import javafx.util.Duration;
//JavaFa app, using a generic model
public class FxMVC extends Application{
#Override
public void start(Stage primaryStage) throws Exception {
FxController fxController = new FxController();
Scene scene = new Scene(fxController.getParent());
primaryStage.setScene(scene);
primaryStage.show();
}
public static void main(String[] args) {
launch(null);
}
}
class FxController{
private final FxView view;
FxController() {
Model model = new Model();
view = new FxView(model);
model.setObserver(view); //register fxView as an observer to model
update(model);
}
//change model
private void update(Model model) {
Random rnd = new Random();
//use javafx animation tools so the change is performed on the JvaxFx application thread
PauseTransition pt = new PauseTransition(Duration.seconds(1));
pt.play();
pt.setOnFinished(e->{
model.setValue(1+rnd.nextInt(model.getMaxValue()));
pt.play();
});
}
Parent getParent(){
return view;
}
}
//View of the MVC pattern. Implements observer to respond to model changes
class FxView extends StackPane implements Observer{
private final Model model;
private final Label label;
public FxView(Model model) {
this.model = model;
label = new Label(" - ");
label.setFont(new Font(label.getFont().getName(), 48));
getChildren().add(label);
}
#Override
public void observableChanged() { //update text in response to change in model
//update text in response to change in model
label.setText(String.format("%d",model.getValue()));
}
}
On the other hand, you can have a model that is more specific, intended to be used with a specific tool-kit, and gain some advantages by using some tool of that tool kit.
For example a model made using JavaFx properties, in this example SimpleIntegerProperty, which simplifies the listening to model changes (does not make use of the Observer interface):
import java.util.Random;
import javafx.animation.PauseTransition;
import javafx.application.Application;
import javafx.beans.property.SimpleIntegerProperty;
import javafx.beans.value.ChangeListener;
import javafx.scene.*;
import javafx.scene.control.Label;
import javafx.scene.layout.StackPane;
import javafx.scene.text.Font;
import javafx.stage.Stage;
import javafx.util.Duration;
//JavaFa app, using a JavaFx model
public class FxApp extends Application{
#Override
public void start(Stage primaryStage) throws Exception {
FxController fxController = new FxController();
Scene scene = new Scene(fxController.getParent());
primaryStage.setScene(scene);
primaryStage.show();
}
public static void main(String[] args) {
launch(null);
}
}
class FxAppController{
private final FxAppView view;
FxAppController() {
FxAppModel model = new FxAppModel();
view = new FxAppView(model);
update(model);
}
//change model
private void update(FxAppModel model) {
Random rnd = new Random();
//use javafx animation tools so the change is performed on the JvaxFx application thread
PauseTransition pt = new PauseTransition(Duration.seconds(1));
pt.play();
pt.setOnFinished(e->{
model.setValue(1+rnd.nextInt(model.getMaxValue()));
pt.play();
});
}
Parent getParent(){
return view;
}
}
//View does not need to implement listener
class FxAppView extends StackPane{
public FxAppView(FxAppModel model) {
Label label = new Label(" - ");
label.setFont(new Font(label.getFont().getName(), 48));
getChildren().add(label);
model.getValue().addListener((ChangeListener<Number>) (obs, oldV, newV) -> label.setText(String.format("%d",model.getValue())));
}
}
//Model that uses JavaFx tools
class FxAppModel {
private SimpleIntegerProperty valueProperty;
private static final int MAX_VALUE = 100;
SimpleIntegerProperty getValue(){
return valueProperty;
}
void setValue(int value){
valueProperty.set(value);
}
int getMaxValue() {
return MAX_VALUE;
}
}
A Swing gui and a JavaFx gui, each uses a different instance of the same Model:
Related
I am trying to add GUIs, created from individual files and add them into my main code.
While it seems to be working, kind of, however, it is missing some elements. For example, in my GridPane, there are a label and a text, both of which are missing. Likewise, for my treeview, there is a treeitem within, however, that is missing as well.
What I am trying to attempt is to reduce the amount of code in the main field and as well as to call relevant events between the Guis, eg. if I select something in the TreeView, that selected TreeItem information will be populated in the GridPane.
Client.java
import javafx.application.Application;
import javafx.scene.Scene;
import javafx.scene.layout.HBox;
import javafx.stage.Stage;
public class Client extends Application
{
private treeviewGui tvGui;
private gridpaneGui inputFieldsGui;
public void init()
{
tvGui = new treeviewGui();
inputFieldsGui = new gridpaneGui();
}
#Override
public void start(Stage topView)
{
topView.setTitle("Test Application");
HBox mainLayout = new HBox(10);
mainLayout.getChildren().addAll(tvGui, inputFieldsGui);
Scene scene = new Scene(mainLayout);
topView.centerOnScreen();
topView.setScene(scene);
topView.show();
}
public static void main(String[] argv)
{
launch(argv);
}
}
treeviewGui.java
import javafx.scene.control.*;
public class treeviewGui extends TreeView
{
private TreeView treeview;
public treeviewGui()
{
treeview = new TreeView();
preload();
}
private void preload()
{
TreeItem<String> newTI = new TreeItem<>("blah");
treeview.setRoot(newTI);
}
}
gridPane.java
import javafx.scene.control.*;
import javafx.scene.layout.*;
import javafx.geometry.Pos;
import javafx.scene.text.Text;
public class gridpaneGui extends GridPane
{
private GridPane gridPane;
public Text fnameTxt;
public gridpaneGui()
{
gridPane = new GridPane();
gridPane.setAlignment(Pos.CENTER);
gridPane.setHgap(5);
gridPane.setVgap(5);
// First Name
Label fnameLbl = new Label("First Name");
fnameTxt = new Text("-");
gridPane.addRow(0, fnameLbl, fnameTxt);
}
public void setFname(String nameStr)
{
fnameTxt.setText(nameStr);
}
}
How can I make a custom Event that triggers on Stage.setScene()?
In my code, the button switches the Scenes and that works fine. However, I would like to extend the Stage to have an additional Event that is triggered when a button or possibly any other Element triggers a setScene.
Example:
package sample;
import javafx.application.Application;
import javafx.scene.Group;
import javafx.scene.Scene;
import javafx.scene.control.Button;
import javafx.stage.Stage;
public class Main extends Application {
public static void main(String[] args) {
Application.launch(args);
}
#Override
public void start(Stage stage) {
Group g1 = new Group();
Button b1 = new Button("2");
g1.getChildren().setAll(b1);
Scene scene1 = new Scene(g1, 50, 50);
Group g2 = new Group();
Button b2 = new Button("1");
g2.getChildren().setAll(b2);
Scene scene2 = new Scene(g2, 50, 50);
stage.setScene(scene1);
stage.setTitle("JavaFX Application Life Cycle");
b1.setOnAction(actionEvent -> {
System.out.println("1");
stage.setScene(scene2);
});
b2.setOnAction(actionEvent -> {
System.out.println("2");
stage.setScene(scene1);
});
stage.show();
}
}
You can add a ChangeListener<Scene> to your Stage like this:
stage.sceneProperty().addListener((observable, oldScene, newScene) -> {
System.out.println("New scene: " + newScene);
System.out.println("Old scene: " + oldScene);
});
I believe using a listener, as shown in the answer by #M.S., is probably the best and simplest way to react to scene changes. However, you ask about how to make a "custom event" that you can fire when the scene changes; by "event" I assume you mean a subclass of javafx.event.Event. So while I recommend sticking with a simple listener, here's an example of a custom event.
First, you need a custom event class:
import javafx.event.Event;
import javafx.event.EventType;
import javafx.scene.Scene;
import javafx.stage.Window;
public class SceneChangedEvent extends Event {
public static final EventType<SceneChangedEvent> SCENE_CHANGED =
new EventType<>(Event.ANY, "SCENE_CHANGED");
public static final EventType<SceneChangedEvent> ANY = SCENE_CHANGED;
private transient Window window;
private transient Scene oldScene;
private transient Scene newScene;
public SceneChangedEvent(Window window, Scene oldScene, Scene newScene) {
super(window, window, SCENE_CHANGED);
this.window = window;
this.oldScene = oldScene;
this.newScene = newScene;
}
public Window getWindow() {
return window;
}
public Scene getOldScene() {
return oldScene;
}
public Scene getNewScene() {
return newScene;
}
}
I'm not sure what information you want to carry with the event so I just added the source Window as well as the old and new Scenes. If you're wondering about the ANY = SCENE_CHANGED, I'm just following the pattern used by javafx.event.ActionEvent (which also only has a single event-type).
Then you simply need to fire the event when the scene changes. To implement this you're still going to need a change listener. As you mention wanting to extend Stage here's an example of that:
import javafx.beans.NamedArg;
import javafx.beans.property.ObjectProperty;
import javafx.beans.property.SimpleObjectProperty;
import javafx.event.EventHandler;
import javafx.stage.Stage;
import javafx.stage.StageStyle;
public class CustomStage extends Stage {
private final ObjectProperty<EventHandler<? super SceneChangedEvent>> onSceneChanged =
new SimpleObjectProperty<>(this, "onSceneChanged") {
#Override
protected void invalidated() {
setEventHandler(SceneChangedEvent.SCENE_CHANGED, get());
}
};
public final void setOnSceneChanged(EventHandler<? super SceneChangedEvent> handler) {
onSceneChanged.set(handler);
}
public final EventHandler<? super SceneChangedEvent> getOnSceneChanged() {
return onSceneChanged.get();
}
public final ObjectProperty<EventHandler<? super SceneChangedEvent>> onSceneChangedProperty() {
return onSceneChanged;
}
public CustomStage() {
this(StageStyle.DECORATED);
}
public CustomStage(#NamedArg(value = "style", defaultValue = "DECORATED") StageStyle style) {
super(style);
sceneProperty().addListener((obs, ov, nv) -> fireEvent(new SceneChangedEvent(this, ov, nv)));
}
}
This would let you react to the scene changing using any of the following:
CustomStage stage = new CustomStage();
// addEventFilter/addEventHandler
stage.addEventFilter(SceneChangedEvent.SCENE_CHANGED, e -> { ... });
stage.addEventHandler(SceneChangedEvent.SCENE_CHANGED, e -> { ... });
// setOnSceneChanged
stage.setOnSceneChanged(e -> { ... });
Keep in mind that the event will only target the CustomStage instance. In other words, only event handlers added to the CustomStage instance will be notified of the event. And as you can see, this is much more complicated than simply adding a change listener to the scene property of the Stage.
I'm using JavaFX to create a Java application which is able to apply a TranslateTransition to a generic node and recall it continuously.
I retrieved a simple right arrow from this url https://www.google.it/search?q=arrow.png&espv=2&source=lnms&tbm=isch&sa=X&ved=0ahUKEwiGheeJvYrTAhWMB5oKHU3-DxgQ_AUIBigB&biw=1600&bih=764#imgrc=rH0TbMkQY2kUaM:
and used it to create the node to translate.
This is my AnimatedNode class:
package application.model.utils.addon;
import javafx.animation.TranslateTransition;
import javafx.scene.Node;
import javafx.util.Duration;
public class AnimatedNode {
private Node node;
private double positionY;
private TranslateTransition translateTransition;
private boolean animated;
private int reverse = 1;
public AnimatedNode(Node node, double animationTime) {
setPositionY(0.0);
setNode(node);
setTranslateTransition(animationTime);
}
public void play() {
if(translateTransition != null && !isAnimated()) {
setAnimated(true);
new Thread() {
#Override
public void run() {
while(isAnimated()) {
translateTransition.setToY(positionY + 50 * reverse);
translateTransition.play();
reverse = -reverse;
setPositionY(translateTransition.getToY());
}
}
}.start();
}
}
public void stop() {
setAnimated(false);
}
public Node getNode() {
return node;
}
private void setNode(Node node) {
this.node = node;
}
public TranslateTransition getTranslateTransition() {
return translateTransition;
}
private void setTranslateTransition(double animationTime) {
translateTransition = new TranslateTransition();
if(node != null) {
translateTransition.setDuration(Duration.seconds(animationTime));
translateTransition.setNode(node);
}
}
public double getPositionY() {
return positionY;
}
private void setPositionY(double positionY) {
this.positionY = positionY;
}
public boolean isAnimated() {
return animated;
}
private void setAnimated(boolean animated) {
this.animated = animated;
}
}
and this is the Application class
package test;
import application.model.utils.addon.AnimatedNode;
import javafx.application.Application;
import javafx.event.EventHandler;
import javafx.scene.Scene;
import javafx.scene.image.Image;
import javafx.scene.image.ImageView;
import javafx.scene.input.MouseButton;
import javafx.scene.input.MouseEvent;
import javafx.scene.layout.BorderPane;
import javafx.scene.layout.Pane;
import javafx.stage.Stage;
public class Test extends Application {
private final String TITLE = "Test application";
private final double WIDTH = 600;
private final double HEIGHT = 400;
private final String ARROW_PATH = "file:resources/png/arrow.png";
private BorderPane rootPane;
#Override
public void start(Stage primaryStage) {
primaryStage.setTitle(TITLE);
rootPane = new BorderPane();
rootPane.setPrefSize(WIDTH, HEIGHT);
Image image = new Image(ARROW_PATH);
ImageView imageView = new ImageView(image);
imageView.setFitWidth(WIDTH);
imageView.setFitHeight(HEIGHT);
imageView.setPreserveRatio(true);
AnimatedNode animatedNode = new AnimatedNode(imageView, 0.7);
Pane pane = new Pane();
pane.getChildren().add(animatedNode.getNode());
pane.setOnMouseClicked(new EventHandler<MouseEvent>() {
#Override
public void handle(MouseEvent arg0) {
if(arg0.getButton().equals(MouseButton.PRIMARY))
animatedNode.play();
if(arg0.getButton().equals(MouseButton.SECONDARY))
animatedNode.stop();
}
});
rootPane.setCenter(pane);
Scene scene = new Scene(rootPane, WIDTH, HEIGHT);
primaryStage.setScene(scene);
primaryStage.show();
}
public static void main(String[] args) {
launch(args);
}
}
The node is added to a generic pane; the pane has a MouseListener. I can start the TranslateTransition by using the primary button of the mouse and stop it with the secondary one.
I used a Thread in the play() method of AnimatedNode but I still have a continuous delay in the transition.
Is this the best way to perform the transition? Can I improve my code?
Thanks a lot for your support.
Sample
This is a simplified example which demonstrates a continuous animation started and stopped by left and right mouse clicks.
import javafx.animation.*;
import javafx.application.Application;
import javafx.scene.Scene;
import javafx.scene.image.*;
import javafx.scene.layout.Pane;
import javafx.stage.Stage;
import javafx.util.Duration;
public class BouncingCat extends Application {
private static final double WIDTH = 100;
private static final double HEIGHT = 100;
private final String ARROW_PATH =
"http://icons.iconarchive.com/icons/iconka/meow-2/64/cat-rascal-icon.png";
// image source: http://www.iconka.com
#Override
public void start(Stage stage) {
Image image = new Image(ARROW_PATH);
ImageView imageView = new ImageView(image);
TranslateTransition animation = new TranslateTransition(
Duration.seconds(0.7), imageView
);
animation.setCycleCount(Animation.INDEFINITE);
animation.setFromY(0);
animation.setToY(50);
animation.setAutoReverse(true);
Pane pane = new Pane(imageView);
Scene scene = new Scene(pane, WIDTH, HEIGHT);
scene.setOnMouseClicked(e -> {
switch (e.getButton()) {
case PRIMARY:
animation.play();
break;
case SECONDARY:
animation.pause();
break;
}
});
stage.setScene(scene);
stage.show();
}
public static void main(String[] args) {
launch(args);
}
}
Advice
You don't need a Thread when you have a Transition. JavaFX will render updated transition frames automatically each pulse.
I don't advise keeping track of properties in a class, when those same values are already represented in the underlying tools you use.
For example:
replace int reverse = 1; with transition.setAutoReverse(true) or transition.setRate(1) (or -1).
replace animated with transition.getStatus().
instead of double positionY, set the toY of the transition.
I wouldn't advise calling your class AnimatedNode unless it extended node, otherwise it is confusing, instead call it something like AnimationControl.
import javafx.animation.TranslateTransition;
import javafx.scene.Node;
import javafx.util.Duration;
public class AnimationControl {
private final TranslateTransition translateTransition;
public AnimationControl(Duration duration, Node node) {
translateTransition = new TranslateTransition(duration, node);
}
public TranslateTransition getTranslateTransition() {
return translateTransition;
}
}
You only need to encapsulate the node and the transition in the AnimationControl and not other fields unless you need further functionality not apparent in your question and not already provided by Node or Transition. If you have that extra functionality then you can enhance the AnimationControl class above to add it.
Exposing the node and the translate transition is enough, as if the user wants to manage the animation, such as starting and stopping it, then the user can just get it from the AnimationControl class. Depending on your use case, the entire AnimationControl class might be unnecessary as you might not need the encapsulation it provides and might instead prefer to just work directly with the node and the transition (as demoed in the sample).
Is there a possibility to use a controller with a JavaFX GUI without using FXML.
I noticed that the FXML file contains an fx-controller attribute to bind the controller but i don't find it an easy way to work with it.
Any ideas about have an MVC arch with JavaFX without using the FXML file or JavaFX Scene Builder ?
Your question isn't particularly clear to me: you just create the classes and basically tie everything together with listeners. I don't know if this helps, but here is a simple example that just has a couple of text fields and a label displaying their sum. This is what I regard as "classical MVC": the view observes the model and updates the UI elements if the model changes. It registers handlers with the UI elements and delegates to the controller if events happen: the controller in turn processes the input (if necessary) and updates the model.
Model:
package mvcexample;
import javafx.beans.property.IntegerProperty;
import javafx.beans.property.ReadOnlyIntegerWrapper;
import javafx.beans.property.SimpleIntegerProperty;
public class AdditionModel {
private final IntegerProperty x = new SimpleIntegerProperty();
private final IntegerProperty y = new SimpleIntegerProperty();
private final ReadOnlyIntegerWrapper sum = new ReadOnlyIntegerWrapper();
public AdditionModel() {
sum.bind(x.add(y));
}
public final IntegerProperty xProperty() {
return this.x;
}
public final int getX() {
return this.xProperty().get();
}
public final void setX(final int x) {
this.xProperty().set(x);
}
public final IntegerProperty yProperty() {
return this.y;
}
public final int getY() {
return this.yProperty().get();
}
public final void setY(final int y) {
this.yProperty().set(y);
}
public final javafx.beans.property.ReadOnlyIntegerProperty sumProperty() {
return this.sum.getReadOnlyProperty();
}
public final int getSum() {
return this.sumProperty().get();
}
}
Controller:
package mvcexample;
public class AdditionController {
private final AdditionModel model ;
public AdditionController(AdditionModel model) {
this.model = model ;
}
public void updateX(String x) {
model.setX(convertStringToInt(x));
}
public void updateY(String y) {
model.setY(convertStringToInt(y));
}
private int convertStringToInt(String s) {
if (s == null || s.isEmpty()) {
return 0 ;
}
if ("-".equals(s)) {
return 0 ;
}
return Integer.parseInt(s);
}
}
View:
package mvcexample;
import javafx.geometry.HPos;
import javafx.geometry.Pos;
import javafx.scene.Parent;
import javafx.scene.control.Label;
import javafx.scene.control.TextField;
import javafx.scene.control.TextFormatter;
import javafx.scene.control.TextFormatter.Change;
import javafx.scene.layout.ColumnConstraints;
import javafx.scene.layout.GridPane;
import javafx.scene.layout.Priority;
public class AdditionView {
private GridPane view ;
private TextField xField;
private TextField yField;
private Label sumLabel;
private AdditionController controller ;
private AdditionModel model ;
public AdditionView(AdditionController controller, AdditionModel model) {
this.controller = controller ;
this.model = model ;
createAndConfigurePane();
createAndLayoutControls();
updateControllerFromListeners();
observeModelAndUpdateControls();
}
public Parent asParent() {
return view ;
}
private void observeModelAndUpdateControls() {
model.xProperty().addListener((obs, oldX, newX) ->
updateIfNeeded(newX, xField));
model.yProperty().addListener((obs, oldY, newY) ->
updateIfNeeded(newY, yField));
sumLabel.textProperty().bind(model.sumProperty().asString());
}
private void updateIfNeeded(Number value, TextField field) {
String s = value.toString() ;
if (! field.getText().equals(s)) {
field.setText(s);
}
}
private void updateControllerFromListeners() {
xField.textProperty().addListener((obs, oldText, newText) -> controller.updateX(newText));
yField.textProperty().addListener((obs, oldText, newText) -> controller.updateY(newText));
}
private void createAndLayoutControls() {
xField = new TextField();
configTextFieldForInts(xField);
yField = new TextField();
configTextFieldForInts(yField);
sumLabel = new Label();
view.addRow(0, new Label("X:"), xField);
view.addRow(1, new Label("Y:"), yField);
view.addRow(2, new Label("Sum:"), sumLabel);
}
private void createAndConfigurePane() {
view = new GridPane();
ColumnConstraints leftCol = new ColumnConstraints();
leftCol.setHalignment(HPos.RIGHT);
leftCol.setHgrow(Priority.NEVER);
ColumnConstraints rightCol = new ColumnConstraints();
rightCol.setHgrow(Priority.SOMETIMES);
view.getColumnConstraints().addAll(leftCol, rightCol);
view.setAlignment(Pos.CENTER);
view.setHgap(5);
view.setVgap(10);
}
private void configTextFieldForInts(TextField field) {
field.setTextFormatter(new TextFormatter<Integer>((Change c) -> {
if (c.getControlNewText().matches("-?\\d*")) {
return c ;
}
return null ;
}));
}
}
Application class:
package mvcexample;
import javafx.application.Application;
import javafx.scene.Scene;
import javafx.stage.Stage;
public class MVCExample extends Application {
#Override
public void start(Stage primaryStage) {
AdditionModel model = new AdditionModel();
AdditionController controller = new AdditionController(model);
AdditionView view = new AdditionView(controller, model);
Scene scene = new Scene(view.asParent(), 400, 400);
primaryStage.setScene(scene);
primaryStage.show();
}
public static void main(String[] args) {
launch(args);
}
}
I use JavaFX extensively and do not use FXML or scenebuilder. So I can vouch that it can be done.
Below is the auto generated code made by my IDE to get an JavaFX main class. This will be the root of your application. You will then add to it to create your application.
public class NewFXMain extends Application {
#Override
public void start(Stage primaryStage) {
Button btn = new Button();
btn.setText("Say 'Hello World'");
btn.setOnAction(new EventHandler<ActionEvent>() {
#Override
public void handle(ActionEvent event) {
System.out.println("Hello World!");
}
});
StackPane root = new StackPane();
root.getChildren().add(btn);
Scene scene = new Scene(root, 300, 250);
primaryStage.setTitle("Hello World!");
primaryStage.setScene(scene);
primaryStage.show();
}
/**
* #param args the command line arguments
*/
public static void main(String[] args) {
launch(args);
}
}
For the rest of us... Here is a VERY simple example showing how to create a JavaFX form without the use of any FXML files. This example can be used within an app that is already running, so I've skipped the Main class and all that ... it's just meant to show the simplicity of JavaFX.
In a nutshell, you simply create your scene based on a container such as an AnchorPane, then you create your Stage and assign the Scene to the stage ... add your controls then show the stage
package javafx;
import javafx.scene.Scene;
import javafx.scene.control.Button;
import javafx.scene.control.TextArea;
import javafx.scene.control.TextField;
import javafx.scene.layout.AnchorPane;
import javafx.stage.Stage;
public class SimpleFX {
private AnchorPane anchorPane;
private TextArea textArea () {
TextArea textArea = new TextArea();
textArea.setLayoutX(20);
textArea.setLayoutY(20);
textArea.setMaxWidth(450);
textArea.setMinHeight(380);
return textArea;
}
private TextField textField () {
TextField textField = new TextField();
textField.setLayoutX(20);
textField.setLayoutY(410);
textField.setMinWidth(450);
textField.setMinHeight(25);
return textField;
}
private Button button() {
Button button = new Button("Button");
button.setLayoutX(240);
button.setLayoutY(450);
return button;
}
private void addControls () {
anchorPane.getChildren().add(0,textArea());
anchorPane.getChildren().add(1,textField());
anchorPane.getChildren().add(2,button());
}
public void startForm () {
anchorPane = new AnchorPane();
Scene scene = new Scene(anchorPane, 500, 500);
Stage stage = new Stage();
stage.setScene(scene);
addControls();
stage.show();
}
}
I have been stuck on this for a while and I am really at my last hope. I really have no idea what the problem can be. I have a GUI project using what I hope is correct MVP form and my problem is I have a presenter object that becomes null in my view class when being used within any method. So far the gui should load and user should hit the button, the method calls the presenter object's method to do something but it is always null. I tried passing into the view class's constructor, making it a object only within the view class, etc and I can't to fix it. Any help is appreciated. I have no idea what is going on and it does not seem to do this to any other object I think
main.java
package main;
import model.Model;
import presenter.Presenter;
import view.View;
public class Main
{
public static void main(String[] args)
{
View view = new View();
Model model = new Model();
Presenter presenter = new Presenter(view, model);
view.setPresenter(presenter);
// this was a way I found on stack overflow to call
// another class that inhierts the application class
// and be able to have args passed if needed
View.launch(View.class, args);
}
}
View.java
package view;
import javafx.application.Application;
import javafx.event.ActionEvent;
import javafx.fxml.FXML;
import javafx.scene.Scene;
import javafx.scene.control.Button;
import javafx.scene.control.TextField;
import javafx.stage.Stage;
import presenter.Presenter;
public class View extends Application
{
private Presenter presenter;
private Button test;
private Views views;
public final static String LOGINVIEW = "loginscreen";
public final static String LOGINVIEWFILE = "FXMLViewLogin.fxml";
public final static String CHATVIEW = "chatscreen";
public final static String CHATVIEWFILE = "FXMLViewChat.fxml";
public View()
{
// init Views class
views = new Views();
}
public void setPresenter(Presenter pres)
{
this.presenter = pres;
}
#Override
public void start(Stage primaryStage)
{
loadViews();
primaryStage.setScene(setView(LOGINVIEW));
primaryStage.setTitle("");
primaryStage.show();
}
private void loadViews()
{
views.loadScreen(LOGINVIEW, LOGINVIEWFILE);
views.loadScreen(CHATVIEW, CHATVIEWFILE);
}
private Scene setView(String name)
{
return views.setView(name);
}
#FXML
private void test(ActionEvent event)
{
//***********************************************************
// ALWAYS NULL IN THIS EVENT METHOD METHOD AND ANY OTHER METHOD FOR THAT FACT AFTER setPresenter
if(presenter == null)
System.out.println("Why is this null right here?");
}
}
Presenter.java
package presenter;
import view.View;
import model.Model;
public class Presenter
{
private Model model;
private View view;
public Presenter(View view, Model model)
{
this.model = model;
this.view = view;
}
// any methods start here
}
Views.java
package view;
import java.util.HashMap;
import javafx.fxml.FXMLLoader;
import javafx.scene.Parent;
import javafx.scene.Scene;
public class Views
{
private final HashMap<String, Parent> view;
public Views()
{
this.view = new HashMap<>();
}
public void addView(String name, Parent screen)
{
view.put(name, screen);
}
public boolean loadScreen(String name, String file)
{
try
{
FXMLLoader myLoader = new FXMLLoader(getClass().getResource(file));
Parent loadScreen = (Parent) myLoader.load();
addView(name, loadScreen);
return true;
}
catch (Exception e)
{
return false;
}
}
public Scene setView(final String name)
{
Scene scene = null;
if (view.get(name) != null)
scene = new Scene(getParentNode(name));
unloadView(name);
return scene;
}
private boolean unloadView(String name)
{
return view.remove(name) != null;
}
private Parent getParentNode(String name)
{
return view.get(name);
}
}