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JavaFX animation does not work in a Stack Pane

I am working on a class assignment, a pong game.
Below is the requirement.
A rectangular paddle moves back and forth via mouse drag along the bottom of the pane;
If the ball connects with the paddle, then it bounces at a 90-degree angle back into the pane space;
The mouse and keyboard actions do not work properly, no response to mouse and keys.
I can't figure out the problem. Any helps will be really appreciated.
PongForOne.java
public class PongForOne extends Application {
#Override
public void start(Stage primaryStage) {
BallPane ball = new BallPane();
PaddlePane paddle = new PaddlePane();
StackPane stkPane = new StackPane();
stkPane.getChildren().addAll(paddle,ball);
paddle.setOnMouseDragged(e -> {
PaddlePane.paddle.setX(e.getX());
});
paddle.setOnKeyPressed(e -> {
switch(e.getCode()){
case LEFT: PaddlePane.paddle.setX(PaddlePane.paddle.getX() - 10); break;
case RIGHT: PaddlePane.paddle.setX(PaddlePane.paddle.getX() + 10); break;
default: break;
}
});
Scene scene = new Scene(stkPane, 300, 400);
primaryStage.setTitle("Hello World!");
primaryStage.setScene(scene);
primaryStage.show();
ball.requestFocus();
paddle.requestFocus();
}
public static void main(String[] args) {
launch(args);
}
}
BallPane.java
public class BallPane extends Pane {
private final double radius = 20;
private double x = radius, y = radius;
private double dx = 1, dy = 1;
private int numBallHitsPaddle = 0;
private int numBallMissPaddle = 0;
private final Circle circle = new Circle(x,y, radius);
private final Text text= new Text (x, y, Integer.toString(numBallHitsPaddle));
private final Timeline animation;
public BallPane(){
circle.setFill(Color.GREEN);
getChildren().addAll(circle, text);
animation = new Timeline(new KeyFrame(Duration.millis(5), e -> moveBall()));
animation.setCycleCount(Timeline.INDEFINITE);
animation.play();
}
public void play(){
animation.play();
}
public void pause(){
animation.pause();
}
public void increaseSpeed(){
animation.setRate(animation.getRate() + 0.1);
}
public void decreaseSpeed(){
animation.setRate(
animation.getRate() > 0 ? animation.getRate() - 0.1 : 0);
}
public void colorChange(){
circle.setFill(Color.color(Math.random(), Math.random(), Math.random()));
}
public DoubleProperty rateProperty(){
return animation.rateProperty();
}
public boolean ballHitsPaddle(){
boolean status = false;
if (x + radius > PaddlePane.getPaddleX() && x - radius < PaddlePane.getPaddleX() + PaddlePane.getPaddleWidth() && y + radius == PaddlePane.getPaddleY()){
status = true;
}
return status;
}
/**
* defines ball's movement
* changes color every time when ball hits paddle and counts the number of hit
*/
public void moveBall(){
if (x < radius || x > getWidth() - radius){
dx *= -1;
}
if ( y > getHeight() - radius){
x = getWidth() / 2;
y = 50;
dx *= -1;
numBallMissPaddle++;
}
if (y < radius || ballHitsPaddle()){
if(ballHitsPaddle()) {
text.setText(Integer.toString(++numBallHitsPaddle));
colorChange();
}
dy *= -1;
}
x += dx;
y += dy;
circle.setCenterX(x);
circle.setCenterY(y);
text.setX(x - 4);
text.setY(y + 3);
}
}
PaddlePane.java
public class PaddlePane extends Pane{
private static final double width = 40, hight = 5;
public static Rectangle paddle = new Rectangle(width, hight);
public PaddlePane(){
paddle.xProperty().bind(widthProperty().divide(2).subtract(width / 2));
paddle.yProperty().bind(heightProperty().subtract(100));
getChildren().add(paddle);
}
public static double getPaddleX(){
return paddle.getX();
}
public static double getPaddleY(){
return paddle.getY();
}
public static double getPaddleWidth(){
return paddle.getWidth();
}
public static double getPaddleHeight(){
return paddle.getHeight();
}
public void colorChange(){
paddle.setFill(Color.color(Math.random(), Math.random(), Math.random()));
}
}

JavaFX reach created object in same view

I got pane where when it loads, it creates rectangles from file (each object is reactangle). That object saves information about rectangles X/Y etc. When it's created I give that rectangle ID to map with hashmap (HashMap<Integer, Radar>) Integer is (rectangle.setId(i.toString());). So base problem here is that after I'm done dragging rectagles I want to save theirs current location. For that reason I tried using
Rectangle rectangle = (Rectangle) pane.lookup(i.toString());
but it just returns null
public class MainWindow {
#FXML
private MenuItem menuItemSave;
#FXML
private AnchorPane pane;
private ViewManager viewManager;
private static final int cubeSize = 10;
private HashMap<Integer, Radar> radarHashMap;
public void initManager(ViewManager viewManager) {
this.viewManager = viewManager;
loadRadars();
}
private double orgSceneX, orgSceneY;
private double orgTranslateX, orgTranslateY;
EventHandler<MouseEvent> rectangleOnMousePressedEventHandler =
new EventHandler<MouseEvent>() {
#Override
public void handle(MouseEvent t) {
orgSceneX = t.getSceneX();
orgSceneY = t.getSceneY();
orgTranslateX = (((Rectangle) (t.getSource())).getTranslateX());
orgTranslateY = (((Rectangle) (t.getSource())).getTranslateY());
}
};
EventHandler<MouseEvent> rectangleOnMouseDraggedEventHandler =
new EventHandler<MouseEvent>() {
#Override
public void handle(MouseEvent t) {
double offsetX = t.getSceneX() - orgSceneX;
double offsetY = t.getSceneY() - orgSceneY;
double newTranslateX = orgTranslateX + offsetX;
double newTranslateY = orgTranslateY + offsetY;
((Rectangle) (t.getSource())).setTranslateX(newTranslateX);
((Rectangle) (t.getSource())).setTranslateY(newTranslateY);
}
};
private void loadRadars() {
radarHashMap = updateCourses();
for (Integer i : radarHashMap.keySet()) {
Rectangle rectangle = new Rectangle(radarHashMap.get(i).getX(), radarHashMap.get(i).getY(), cubeSize, cubeSize);
rectangle.setFill(Color.YELLOW);
rectangle.setCursor(Cursor.HAND);
rectangle.setId(i.toString());
rectangle.setOnMousePressed(rectangleOnMousePressedEventHandler);
rectangle.setOnMouseDragged(rectangleOnMouseDraggedEventHandler);
pane.getChildren().add(rectangle);
}
}
#FXML
void SaveChanges(ActionEvent event) {
for (Integer i : radarHashMap.keySet()) {
Rectangle rectangle = (Rectangle) pane.lookup(i.toString());
System.out.println(rectangle.getId());
System.out.println(rectangle.getY());
}
}
}

Rectangle rectangle = (Rectangle) pane.lookup("#"+i.toString());

Graphics Stuttering in Java (Space Invaders)

I am creating a Space Invaders Game with just one Invader. The images are stuttering and are only visible ~10% of the time. What is wrong with my code?
package spaceinvader;
import javax.swing.*;
import java.awt.event.*;
import java.awt.*;
public class spaceInvaders extends JApplet implements KeyListener, ActionListener
{
//Declare components and variables
JPanel mainPanel = new JPanel();
ImageIcon carImage = new ImageIcon("ship.png");
ImageIcon invaderImage = new ImageIcon("invader.png");
int intPosX = 240;
int intPosY = 330;
int intXAmount = 15;
boolean shipMoveLeft = false;
boolean shipMoveRight = false;
Timer shipTimer = new Timer(100,this);
int intBulletX = -50;
int intBulletY = -50;
boolean bulletMove = false;
boolean bulletActive = false;
Timer bulletTimer = new Timer(50,this);
int intInvaderX = 0;
int intInvaderY = 0;
int invaderXAmount = 10;
boolean invaderMove = true;
Timer invaderTimer= new Timer(1000,this);
public void init()
{
addKeyListener(this);
setFocusable(true);
resize(600,400);
setContentPane(mainPanel);
shipTimer.start();
bulletTimer.start();
invaderTimer.start();
}
public void actionPerformed(ActionEvent e)
{
requestFocus();
if(shipMoveLeft)
intPosX += intXAmount;
else if(shipMoveRight)
intPosX -= intXAmount;
if(bulletMove && bulletActive){
intBulletY -= 15;
if(intBulletY <= -50){
bulletMove = false;
bulletActive = false;
}
}
if(invaderMove){
intInvaderX += invaderXAmount;
if(intInvaderX > getWidth() - 60 || intInvaderX < 0){
intInvaderY += 40;
invaderXAmount *= -1;
}
}
repaint();
}
public void keyPressed(KeyEvent e)
{
int key = e.getKeyCode();
if (key == 37){
shipMoveRight = true;
}
else if (key == 39){
shipMoveLeft = true;
}
else if (key == 32){
if(bulletActive == false){
intBulletX = intPosX;
intBulletY = intPosY;
}
bulletMove = true;
bulletActive = true;
}
}
public void keyReleased(KeyEvent e)
{
shipMoveLeft = false;
shipMoveRight = false;
}
public void keyTyped(KeyEvent e)
{
}
public void paint(Graphics gr)
{
super.paint(gr);
gr.setColor(Color.red);
gr.fillOval(intBulletX, intBulletY, 10, 25);
carImage.paintIcon(this,gr, intPosX, intPosY); //Draw image in new spot
invaderImage.paintIcon(this,gr, intInvaderX, intInvaderY);
}
}

So there are a number of issues which jump out immediately...
Applets are a dead end, most browsers will actively block them and/or have dropped support for the plugin
You're adding a JPanel to the applet, but overriding the applet's paint method, because of the way painting can work, the panel can be painted independently of the applet, causing it to paint over whatever you might have painted
You don't need multiple timers, you just need to have better delta values (smaller been faster)
KeyListener is a poor choice for detecting keyboard input, it's rather low level and has focus related issues which are easily overcome by using the Key Bindings API
I'd start by having a look at Performing Custom Painting, Painting in AWT and Swing and How to Use Key Bindings for more details.
So how would you start fixing it? Start by using a JPanel as you basic container, override it's paintComponent and place all your paint logic here.
Use a single Timer to manage the updates
There are any number of approaches you can take, but I'd start with defining some contracts that define what can go on in the game
public interface GameSpace extends ImageObserver {
public Dimension getGameSpace();
public boolean hasInput(Input input);
}
public interface Entity {
public void paint(GameSpace gameSpace, Graphics2D g2d);
public boolean update(GameSpace gameSpace);
public Rectangle getBounds();
}
public abstract class AbstractEntity implements Entity {
private int x;
private int y;
public int getX() {
return x;
}
public int getY() {
return y;
}
public void setX(int x) {
this.x = x;
}
public void setY(int y) {
this.y = y;
}
protected abstract int getWidth();
protected abstract int getHeight();
public Rectangle getBounds() {
return new Rectangle(getX(), getY(), getWidth(), getHeight());
}
}
public abstract class AbstractImageEntity extends AbstractEntity {
protected abstract BufferedImage getImage();
#Override
protected int getWidth() {
return getImage().getWidth();
}
#Override
protected int getHeight() {
return getImage().getHeight();
}
}
This separates some of management of key elements, allowing for a more flexible design. You might have a lot more entities, one's which could move, ones which could not, some which are painted, some which are not, but all which provide support for the core engine to get work done.
Once you have that you can start defining some core entities you need
public class ShipEntity extends AbstractImageEntity {
private BufferedImage ship;
public ShipEntity(GameSpace gameSpace) throws IOException {
ship = ImageIO.read(getClass().getResource("/resources/ship.png"));
setY(gameSpace.getGameSpace().height - getBounds().height);
setX((gameSpace.getGameSpace().width - getBounds().width) / 2);
}
#Override
public BufferedImage getImage() {
return ship;
}
#Override
public void paint(GameSpace gameSpace, Graphics2D g2d) {
g2d.drawImage(ship, getX(), getY(), gameSpace);
}
#Override
public boolean update(GameSpace gameSpace) {
int x = getX();
if (gameSpace.hasInput(Input.LEFT)) {
x -= 2;
}
if (gameSpace.hasInput(Input.RIGHT)) {
x += 2;
}
if (x < 0) {
x = 0;
} else if (x + getWidth() > gameSpace.getGameSpace().width) {
x = gameSpace.getGameSpace().width - getWidth();
}
setX(x);
return true;
}
}
public class InvaderEntity extends AbstractImageEntity {
private BufferedImage invader;
public InvaderEntity() throws IOException {
invader = ImageIO.read(getClass().getResource("/resources/Invader.png"));
}
#Override
protected BufferedImage getImage() {
return invader;
}
#Override
public void paint(GameSpace gameSpace, Graphics2D g2d) {
g2d.drawImage(invader, getX(), getY(), gameSpace);
}
#Override
public boolean update(GameSpace gameSpace) {
return true;
}
}
public class ProjectileEntity extends AbstractEntity {
private int delta;
public ProjectileEntity(int delta) {
this.delta = delta;
}
#Override
protected int getWidth() {
return 10;
}
#Override
protected int getHeight() {
return 10;
}
#Override
public void paint(GameSpace gameSpace, Graphics2D g2d) {
g2d.setColor(Color.RED);
int width = getWidth();
int height = getHeight();
g2d.fillOval(getX() - width / 2, getY() - height / 2, width, height);
}
#Override
public boolean update(GameSpace gameSpace) {
int y = getY() + delta;
setY(getY() + delta);
return y + getHeight() >= 0 && y + getHeight() <= gameSpace.getGameSpace().height;
}
}
Basically, they contain the logic required for getting their jobs done.
Finally, you need to setup the actual game UI
public class GamePane extends JPanel implements GameSpace {
private Set<Input> inputs;
private Entity playerEntity;
private List<Entity> projectileEntities;
private List<Entity> invaderEntities;
private long timeOfLastProjectile = -1;
public GamePane() throws IOException {
setBackground(Color.BLACK);
inputs = new HashSet<>(2);
playerEntity = new ShipEntity(this);
projectileEntities = new ArrayList<>(25);
invaderEntities = new ArrayList<>(25);
InvaderEntity invader = new InvaderEntity();
invader.setX((getGameSpace().width - invader.getBounds().width) / 2);
invader.setY((getGameSpace().height - invader.getBounds().height) / 2);
invaderEntities.add(invader);
addKeyBinding(Input.LEFT, "left", KeyEvent.VK_LEFT);
addKeyBinding(Input.RIGHT, "right", KeyEvent.VK_RIGHT);
addKeyBinding(Input.SPACE, "space", KeyEvent.VK_SPACE);
Timer timer = new Timer(15, new ActionListener() {
#Override
public void actionPerformed(ActionEvent e) {
updateState();
processCollisions();
repaint();
}
});
timer.start();
}
#Override
public Dimension getPreferredSize() {
return new Dimension(800, 800);
}
protected void updateState() {
playerEntity.update(this);
if (hasInput(Input.SPACE)) {
long time = System.currentTimeMillis() - timeOfLastProjectile;
if (time < 0 || time > 1000) {
timeOfLastProjectile = System.currentTimeMillis();
Rectangle bounds = playerEntity.getBounds();
ProjectileEntity projectile = new ProjectileEntity(-1);
int x = bounds.x + ((bounds.width - projectile.getWidth()) / 2);
int y = bounds.y - projectile.getHeight();
projectile.setX(x);
projectile.setY(y);
projectileEntities.add(projectile);
}
}
for (Entity entity : invaderEntities) {
entity.update(this);
}
List<Entity> outOfBounds = new ArrayList<>(25);
for (Entity entity : projectileEntities) {
if (!entity.update(this)) {
outOfBounds.add(entity);
}
}
projectileEntities.removeAll(outOfBounds);
}
protected void processCollisions() {
Set<Entity> hitInvaders = new HashSet<>(25);
Set<Entity> hitProjectiles = new HashSet<>(25);
for (Entity invader : invaderEntities) {
for (Entity projectile : projectileEntities) {
if (projectile.getBounds().intersects(invader.getBounds())) {
// Maybe lots of cool explosiions
hitInvaders.add(invader);
hitProjectiles.add(projectile);
}
}
}
invaderEntities.removeAll(hitInvaders);
projectileEntities.removeAll(hitProjectiles);
}
protected void addKeyBinding(Input input, String name, int virtualKey) {
ActionMap am = getActionMap();
InputMap im = getInputMap(WHEN_IN_FOCUSED_WINDOW);
im.put(KeyStroke.getKeyStroke(virtualKey, 0, false), name + ".pressed");
im.put(KeyStroke.getKeyStroke(virtualKey, 0, true), name + ".released");
am.put(name + ".pressed", new KeyAction(inputs, input, true));
am.put(name + ".released", new KeyAction(inputs, input, false));
}
#Override
public Dimension getGameSpace() {
return getPreferredSize();
}
#Override
public boolean hasInput(Input input) {
return inputs.contains(input);
}
#Override
protected void paintComponent(Graphics g) {
super.paintComponent(g);
Graphics2D g2d = (Graphics2D) g.create();
playerEntity.paint(this, g2d);
g2d.dispose();
for (Entity entity : invaderEntities) {
g2d = (Graphics2D) g.create();
entity.paint(this, g2d);
g2d.dispose();
}
for (Entity entity : projectileEntities) {
g2d = (Graphics2D) g.create();
entity.paint(this, g2d);
g2d.dispose();
}
}
}
public class KeyAction extends AbstractAction {
private Input input;
private Set<Input> inputs;
private boolean pressed;
public KeyAction(Set<Input> inputs, Input input, boolean pressed) {
this.input = input;
this.inputs = inputs;
this.pressed = pressed;
}
#Override
public void actionPerformed(ActionEvent e) {
if (pressed) {
inputs.add(input);
} else {
inputs.remove(input);
}
}
}
Now you could go a little further and generate an "engine" class which controls the entities and performs all the required updating, but I'm lazy ;)
That's a really rough idea of some the basic concepts you need to develop to be able to move forward, hope it helps

Extend content of a Scrollpane if smaller than viewport

I want to make a ScrollPane with a custom Pane inside, that has two Children. One that holds my objects and one just for the background. I want to make it so if I zoom out, and the content is smaller than the viewport, then the size of the content would expand, filling in the new place in the viewport. And if I zoom back then it would remain the same, and I have now a larger content in area. The new width of the content would be: originalWidth + viewportWidth - scaledWidth.
I have made the grid, and the zooming works, but I can't make it so that it resizes the content. I have tried to set the content size when zooming to the current viewport size, but it does not work.
Question:
What am I doing wrong?
The layout is defined in fxml. Another than ScrollPane content set to fill height and width nothing out of ordinary there.
CustomPane class:
public class CustomPane extends StackPane implements Initializable {
#FXML
StackPane view;
#FXML
AnchorPane objectPane;
#FXML
GriddedPane background;
private DoubleProperty zoomFactor = new SimpleDoubleProperty(1.5);
private BooleanProperty altStatus = new SimpleBooleanProperty(false);
public CustomPane() {
super();
FXMLLoader loader = new FXMLLoader();
loader.setLocation(getClass().getClassLoader().getResource("CustomCanvas.fxml"));
loader.setController(this);
loader.setRoot(this);
try {
loader.load();
} catch (IOException e) {
e.printStackTrace();
}
}
#Override
public void initialize(URL location, ResourceBundle resources) {
objectPane.setStyle("-fx-background-color: transparent");
objectPane.prefWidthProperty().bind(prefWidthProperty());
objectPane.prefHeightProperty().bind(prefHeightProperty());
objectPane.getChildren().add(new Circle(512, 378, 20, Color.RED));
}
public void zoom(ScrollPane parent, Node node, double factor, double x, double y) {
Timeline timeline = new Timeline(60);
// determine scale
double oldScale = node.getScaleX();
double scale = oldScale * factor;
double f = (scale / oldScale) - 1;
// determine offset that we will have to move the node
Bounds bounds = node.localToScene(node.getBoundsInLocal());
double dx = (x - (bounds.getWidth() / 2 + bounds.getMinX()));
double dy = (y - (bounds.getHeight() / 2 + bounds.getMinY()));
// timeline that scales and moves the node
timeline.getKeyFrames().clear();
timeline.getKeyFrames().addAll(
new KeyFrame(Duration.millis(100), new KeyValue(node.translateXProperty(), node.getTranslateX() - f * dx)),
new KeyFrame(Duration.millis(100), new KeyValue(node.translateYProperty(), node.getTranslateY() - f * dy)),
new KeyFrame(Duration.millis(100), new KeyValue(node.scaleXProperty(), scale)),
new KeyFrame(Duration.millis(100), new KeyValue(node.scaleYProperty(), scale))
);
timeline.play();
Bounds viewportBounds = parent.getViewportBounds();
if (bounds.getWidth() < viewportBounds.getWidth()) {
setMinWidth(viewportBounds.getWidth());
requestLayout();
}
if (getMinHeight() < viewportBounds.getHeight()) {
setMinHeight(viewportBounds.getHeight());
requestLayout();
}
}
public final Double getZoomFactor() {
return zoomFactor.get();
}
public final void setZoomFactor(Double zoomFactor) {
this.zoomFactor.set(zoomFactor);
}
public final DoubleProperty zoomFactorProperty() {
return zoomFactor;
}
public boolean getAltStatus() {
return altStatus.get();
}
public BooleanProperty altStatusProperty() {
return altStatus;
}
public void setAltStatus(boolean altStatus) {
this.altStatus.set(altStatus);
}
}
Controller class:
public class Controller implements Initializable {
public ScrollPane scrollPane;
public CustomPane customPane;
public AnchorPane anchorPane;
public Tab tab1;
#Override
public void initialize(URL location, ResourceBundle resources) {
scrollPane.viewportBoundsProperty().addListener((observable, oldValue, newValue) -> {
customPane.setMinSize(newValue.getWidth(), newValue.getHeight());
});
scrollPane.requestLayout();
tab1.getTabPane().addEventFilter(KeyEvent.KEY_PRESSED, event1 -> {
if (event1.getCode() == KeyCode.ALT)
customPane.setAltStatus(true);
});
tab1.getTabPane().addEventFilter(KeyEvent.KEY_RELEASED, event1 -> {
if (event1.getCode() == KeyCode.ALT)
customPane.setAltStatus(false);
});
scrollPane.setOnScroll(event -> {
double zoomFactor = 1.5;
if (event.getDeltaY() <= 0)
zoomFactor = 1 / zoomFactor;
customPane.setZoomFactor(zoomFactor);
if (customPane.getAltStatus())
customPane.zoom(scrollPane, customPane, customPane.getZoomFactor(), event.getSceneX(), event.getSceneY());
});
}
}
GriddedPane class:
public class GriddedPane extends Pane implements Initializable {
DoubleProperty gridWidth = new SimpleDoubleProperty(this, "gridWidth", 10);
DoubleProperty gridHeight = new SimpleDoubleProperty(this, "gridHeight", 10);
public GriddedPane() {
super();
}
#Override
public void initialize(URL location, ResourceBundle resources) {
}
#Override
protected void layoutChildren() {
getChildren().clear();
setMouseTransparent(true);
toBack();
for (int i = 0; i < getHeight(); i += getGridWidth())
getChildren().add(makeLine(0, i, getWidth(), i, "x"));
for (int i = 0; i < getWidth(); i += getGridHeight())
getChildren().add(makeLine(i, 0, i, getHeight(), "y"));
}
public void redrawLines() {
for (Node n : getChildren()) {
Line l = (Line) n;
if (l.getUserData().equals("x")) {
l.setEndX(getWidth());
} else if (l.getUserData().equals("y")) {
l.setEndY(getHeight());
}
}
}
private Line makeLine(double sx, double sy, double ex, double ey, String data) {
final Line line = new Line(sx, sy, ex, ey);
if (ex % (getGridWidth() * 10) == 0.0) {
line.setStroke(Color.BLACK);
line.setStrokeWidth(0.3);
} else if (ey % (getGridHeight() * 10) == 0.0) {
line.setStroke(Color.BLACK);
line.setStrokeWidth(0.3);
} else {
line.setStroke(Color.GRAY);
line.setStrokeWidth(0.1);
}
line.setUserData(data);
return line;
}
public double getGridWidth() {
return gridWidth.get();
}
public DoubleProperty gridWidthProperty() {
return gridWidth;
}
public void setGridWidth(double gridWidth) {
this.gridWidth.set(gridWidth);
}
public double getGridHeight() {
return gridHeight.get();
}
public DoubleProperty gridHeightProperty() {
return gridHeight;
}
public void setGridHeight(double gridHeight) {
this.gridHeight.set(gridHeight);
}
}

Not really sure if I unterstood what you want to achieve. But if your goal is to make the content of the scrollPane never get smaller than the scrollPane's width, this does the job for me:
public class Zoom extends Application {
#Override
public void start(Stage primaryStage) {
ImageView imageView = new ImageView(new Image(someImage));
ScrollPane scrollPane = new ScrollPane(imageView);
StackPane root = new StackPane(scrollPane);
imageView.fitWidthProperty().bind(scrollPane.widthProperty());
imageView.fitHeightProperty().bind(scrollPane.heightProperty());
scrollPane.setOnScroll(evt -> {
boolean zoomOut = evt.getDeltaY() < 0;
double zoomFactor = zoomOut ? -0.2 : 0.2;
imageView.setScaleX(imageView.getScaleX() + zoomFactor);
imageView.setScaleY(imageView.getScaleY() + zoomFactor);
if (zoomOut) {
Bounds bounds = imageView.getBoundsInParent();
if (bounds.getWidth() < scrollPane.getWidth()) {
imageView.setScaleX(1);
imageView.setScaleY(1);
}
}
});
primaryStage.setScene(new Scene(root));
primaryStage.show();
}
public static void main(String[] args) {
launch(args);
}
}

Draw circle in border of rectangle in JavaFX

I want add some circles in border of a rectangle in event onMouseMoved.
Need to develop a graph using JavaFX and these circles will serve to connect the edges to the graph nodes.
See the image below:
I'm using JavaFX.
See you the code:
public class SampleDragAndDrop extends Application {
public static void main(String[] args) throws Exception {
launch(args);
}
#Override
public void start(final Stage stage) throws Exception {
DoubleProperty entity1X = new SimpleDoubleProperty(100);
DoubleProperty entity1Y = new SimpleDoubleProperty(100);
Entity entity1 = new Entity(Color.STEELBLUE, entity1X, entity1Y);
Screen screen = Screen.getPrimary();
Rectangle2D bounds = screen.getVisualBounds();
stage.setX(bounds.getMinX());
stage.setY(bounds.getMinY());
stage.setWidth(bounds.getWidth());
stage.setHeight(bounds.getHeight());
stage.setTitle("Draw circle in rectangle");
stage.setScene(new Scene(new Group(entity1), 400, 400, Color.ALICEBLUE));
stage.show();
}
class Anchor extends Circle {
Anchor(Color color, DoubleProperty x, DoubleProperty y) {
super(x.get(), y.get(), 20);
setFill(color.deriveColor(1, 1, 1, 0.5));
setStroke(color);
setStrokeWidth(2);
setStrokeType(StrokeType.OUTSIDE);
x.bind(centerXProperty());
y.bind(centerYProperty());
}
class Entity extends Rectangle {
Entity(Color color, DoubleProperty x, DoubleProperty y) {
setX(x.get());
setY(y.get());
setWidth(120);
setHeight(50);
setFill(color.deriveColor(1, 1, 1, 0.5));
setStroke(color);
setStrokeWidth(2);
setStrokeType(StrokeType.OUTSIDE);
setArcWidth(20);
setArcHeight(20);
x.bind(xProperty());
y.bind(yProperty());
enableDrag();
}
private void enableDrag() {
final Entity.Delta dragDelta = new Entity.Delta();
setOnMousePressed(new EventHandler<MouseEvent>() {
#Override
public void handle(MouseEvent mouseEvent) {
// record a delta distance for the drag and drop operation.
dragDelta.x = getX() - mouseEvent.getX();
dragDelta.y = getY() - mouseEvent.getY();
getScene().setCursor(Cursor.MOVE);
}
});
setOnMouseReleased(new EventHandler<MouseEvent>() {
#Override
public void handle(MouseEvent mouseEvent) {
getScene().setCursor(Cursor.HAND);
}
});
setOnMouseDragged(new EventHandler<MouseEvent>() {
#Override
public void handle(MouseEvent mouseEvent) {
double newX = mouseEvent.getX() + dragDelta.x;
if (newX > 0 && newX < getScene().getWidth()) {
setX(newX);
}
double newY = mouseEvent.getY() + dragDelta.y;
if (newY > 0 && newY < getScene().getHeight()) {
setY(newY);
}
}
});
setOnMouseEntered(new EventHandler<MouseEvent>() {
#Override
public void handle(MouseEvent mouseEvent) {
if (!mouseEvent.isPrimaryButtonDown()) {
getScene().setCursor(Cursor.HAND);
}
}
});
setOnMouseExited(new EventHandler<MouseEvent>() {
#Override
public void handle(MouseEvent mouseEvent) {
if (!mouseEvent.isPrimaryButtonDown()) {
getScene().setCursor(Cursor.DEFAULT);
}
}
});
setOnMouseMoved(new EventHandler<MouseEvent>(){
#Override
public void handle(MouseEvent mouseEvent) {
// Create circles in rectangle here
}
});
}
private class Delta {
double x, y;
}
}
}
How can I do?
Thank you!

This works:
// Create circles in rectangle here
// Not sure you really need these?
DoubleProperty leftX = new SimpleDoubleProperty();
DoubleProperty leftY = new SimpleDoubleProperty();
Anchor leftAnchor = new Anchor(Color.STEELBLUE, leftX, leftY);
leftAnchor.centerXProperty().bind(xProperty());
leftAnchor.centerYProperty().bind(yProperty().add(heightProperty().divide(2)));
((Group)getParent()).getChildren().add(leftAnchor);