跟踪同时按下两个或多个键

试试看

final BooleanProperty spacePressed = new SimpleBooleanProperty(false);
final BooleanProperty rightPressed = new SimpleBooleanProperty(false);
final BooleanBinding spaceAndRightPressed = spacePressed.and(rightPressed);

// How to respond to both keys pressed together:
spaceAndRightPressed.addListener(new ChangeListener<Boolean>() {
    @Override
    public void changed(ObservableValue<Boolean> obs, Boolean werePressed, Boolean arePressed) {
        System.out.println("Space and right pressed together");
    }
});

// Wire up properties to key events:
scene.setOnKeyPressed(new EventHandler<KeyEvent>() {
    @Override
    public void handle(KeyEvent ke) {
        if (ke.getCode() == KeyCode.SPACE) {
            spacePressed.set(true);
        } else if (ke.getCode() == KeyCode.RIGHT) {
            rightPressed.set(true);
        }
    }
});

scene.setOnKeyReleased(new EventHandler<KeyEvent>() {
    @Override
    public void handle(KeyEvent ke) {
        if (ke.getCode() == KeyCode.SPACE) {
            spacePressed.set(false);
        } else if (ke.getCode() == KeyCode.RIGHT) {
            rightPressed.set(false);
        }
    }
});

我自己补充一下：

javafx.scene.input 包有一个方便的 KeyCodeCombination 类，其构造函数接受键和修饰符的组合作为属性。这个类实现了 match(KeyEvent e) 方法

使用示例：

public void start(Stage primaryStage) throws Exception {
    Label l = new Label();
    Pane p = new Pane(l);
    Scene s = new Scene(p, 200, 200);

    KeyCodeCombination kComb = new KeyCodeCombination(KeyCode.A, KeyCombination.ALT_ANY);

    s.setOnKeyPressed(e -> {
        if (kComb.match(e))
            l.setText("Hello");
    });

    primaryStage.setScene(s);
    primaryStage.show();
}