Question

我有Pane：

pane.addEventFilter(MouseEvent.ANY, new EventsHandler(e -> System.out.println(""), e -> { 
     createEvents(e.getX(), e.getY());
})});

方法createEvents：

Circle circle = new Circle(x, y, 5);
circle.addEventFilter(MouseEvent.MOUSE_CLICKED, event -> System.out.println("Clicked!"));
pane.getChildren().add(circle);

当我点击一个圆圈时，它会调用两个事件：字符串单击并创建一个新事件。你怎么没有将点击事件传递给父母？

我的EvendsHandler添加窗格：

public class EventsHandler implements EventHandler<MouseEvent> {

    private final EventHandler<MouseEvent> onDraggedEventHandler;
    private final EventHandler<MouseEvent> onClickedEventHandler;

    private boolean dragging = false;

    public EventsHandler(EventHandler<MouseEvent> onDraggedEventHandler, EventHandler<MouseEvent> onClickedEventHandler) {
        this.onDraggedEventHandler = onDraggedEventHandler;
        this.onClickedEventHandler = onClickedEventHandler;
    }

    @Override
    public void handle(MouseEvent event) {
        if (event.getEventType() == MouseEvent.MOUSE_PRESSED) {
            dragging = false;
        } else if (event.getEventType() == MouseEvent.DRAG_DETECTED) {
            dragging = true;
        } else if (event.getEventType() == MouseEvent.MOUSE_DRAGGED) {
            // maybe filter on dragging (== true)
            onDraggedEventHandler.handle(event);
        } else if (event.getEventType() == MouseEvent.MOUSE_CLICKED) {
            if (!dragging) {
                onClickedEventHandler.handle(event);
            }}}}

Answer 1

您正在使用事件过滤器。在从根到目标节点的遍历中调用过滤器。由于在调用节点自己的过滤器之前调用了祖先的所有过滤器，因此节点的过滤器不可能阻止父过滤器的执行。

您应该使用事件 处理程序 ，这些事件在从目标节点遍历到根节点时被调用，并允许您通过使用事件处理程序来阻止执行父事件处理程序事件：

pane.addEventHandler(MouseEvent.ANY, new EventsHandler(e -> System.out.println(""), e -> { 
     createEvents(e.getX(), e.getY());
})});

circle.addEventHandler(MouseEvent.MOUSE_CLICKED, event -> {
    System.out.println("Clicked!");
    event.consume();
});

注意：如果您只为特定事件类型注册单个事件处理程序，则可以指定例如onMouseClicked属性而非使用addEventHandler：

circle.setOnMouseClicked(event -> {
    System.out.println("Clicked!");
    event.consume();
});

JavaFX如何不将事件传递给父级

1 个答案: