如何将事件从一个节点发送到另一节点 [英] How to send events from one Node to another Node

问题描述

我有一个Pane，它监听滚轮鼠标的滚动；我还有一个滚动条，它会自动侦听滚轮鼠标的滚动.我想知道如何将窗格"捕获的滚动事件发送到滚动条.

I have a Pane which listens for the wheel mouse scroll; as well I have a scroll bar which automatically listens for the wheel mouse scroll. I would like to know how to send to scroll event captured by the Pane to the Scrollbar.

我无法使用滚动窗格，因为我需要对窗格进行自定义实现，我已经尝试使用滚动窗格，但它不能满足我的需求.

I can’t use a scroll pane because I need a custom implementation of the pane, I already tried to use a scroll pane and it did not cover my needs.

我试图触发事件和其他方法，但是我只是可以将事件传递/传播/发送到滚动条.

I tried to fire the event and other method but I just can get the event to be passed/propagated/sent to the scrollbar.

预先感谢

示例应用程序:

package com.test;

import javafx.application.Application;
import javafx.beans.value.ChangeListener;
import javafx.beans.value.ObservableValue;
import javafx.event.Event;
import javafx.event.EventHandler;
import javafx.geometry.Orientation;
import javafx.scene.Scene;
import javafx.scene.control.ScrollBar;
import javafx.scene.input.ScrollEvent;
import javafx.scene.layout.BorderPane;
import javafx.scene.layout.Pane;
import javafx.stage.Stage;

public class ScrollTest extends Application{

   @Override
   public void start(Stage primaryStage) throws Exception {


     final BorderPane root = new BorderPane();

     final Pane pane = new Pane();
     root.setCenter(pane);

     final ScrollBar scrollBar = new ScrollBar();
     root.setRight(scrollBar);


     pane.addEventFilter(ScrollEvent.ANY, new EventHandler<ScrollEvent>(){
        @Override
        public void handle(ScrollEvent arg0) {
           System.out.println("scrolling on the pane");

           Event.fireEvent(scrollBar, arg0);
//           scrollBar.getEventDispatcher().dispatchEvent(arg0, arg1)
        }
     });



     scrollBar.setOrientation(Orientation.VERTICAL);
     scrollBar.valueProperty().addListener(new ChangeListener<Number>() {
        @Override
        public void changed(ObservableValue<? extends Number> ov, Number old_val, final Number new_val) {
           System.out.println("scrollBar.valueProperty() changed");
        }
     });


     primaryStage.setScene(new Scene(root, 600, 600));
     primaryStage.show();
   }

   public static void main(String[] args) {
      launch(args);
   }

}

推荐答案

似乎，您的问题等同于自定义滚动窗格实现的需要.

Seems, you question is equal to the need of custom scroll pane implementation.

我认为，一种可能的方法是-在事件发生时解析事件，并使滚动条更改其值(在窗格上的事件上添加侦听器，解析是向上滚动还是向下滚动，并使用方法递增或递​​减滚动栏).

I think, a possible way - is to parse event, and make scroll bar change its value, when event comes (add listener on event on pane, parse whether scroll up or down, and use method increment or decrement of the scroll bar).

此外，我们使用一些实现来发送滚动事件.将此草稿用于您的实现:

Also, we use some implementation for scroll event sending. Use this scratch for your implementation :

/**
 * Send ScrollEvent in the center of the control
 *
 * @param wrap Wrap, which will receive event
 * @param scrollX Number of pixels to scroll by x coordinate
 * @param scrollY Number of pixels to scroll by y coordinate
 */
protected static void sendScrollEvent(final Scene scene, Node node, double scrollX, double scrollY) {
    double x = node.getLayoutBounds().getWidth() / 4;
    double y = node.getLayoutBounds().getHeight() / 4;
    sendScrollEvent(scene, node, scrollX, scrollY, ScrollEvent.HorizontalTextScrollUnits.NONE, scrollX, ScrollEvent.VerticalTextScrollUnits.NONE, scrollY, x, y, node.getLayoutBounds().getMinX() + x, node.getLayoutBounds().getMinY() + y);
}

protected static void sendScrollEvent(final Scene scene, final Node node,
        double _scrollX, double _scrollY,
        ScrollEvent.HorizontalTextScrollUnits _scrollTextXUnits, double _scrollTextX,
        ScrollEvent.VerticalTextScrollUnits _scrollTextYUnits, double _scrollTextY,
        double _x, double _y,
        double _screenX, double _screenY) {
    //For 2.1.0 :
    //final ScrollEvent scrollEvent = ScrollEvent.impl_scrollEvent(_scrollX, _scrollY, _scrollTextXUnits, _scrollTextX, _scrollTextYUnits, _scrollTextY, _x, _y, _screenX, _screenY, false, false, false, false);
    //For 2.2.0 :
    //Interpretation: EventType<ScrollEvent> eventType, double _scrollX, double _scrollY, double _totalScrollX, double _totalScrollY, HorizontalTextScrollUnits _scrollTextXUnits, double _scrollTextX, VerticalTextScrollUnits _scrollTextYUnits, double _scrollTextY, int _touchPoints, double _x, double _y, double _screenX, double _screenY, boolean _shiftDown, boolean _controlDown, boolean _altDown, boolean _metaDown, boolean _direct, boolean _inertia)
    //For 8.0 before b64 and RT-9383
    //final ScrollEvent scrollEvent = new ScrollEvent.impl_scrollEvent(ScrollEvent.SCROLL, _scrollX, _scrollY, _scrollX, _scrollY, _scrollTextXUnits, _scrollTextX, _scrollTextYUnits, _scrollTextY, 0, _x, _y, _screenX, _screenY, false, false, false, false, false, false);

    //new ScrollEvent(EventType<ScrollEvent> eventType, 
    //double x, double y, double screenX, double screenY, 
    //boolean shiftDown, boolean controlDown, boolean altDown, boolean metaDown, 
    //boolean direct, boolean inertia, double deltaX, double deltaY, double gestureDeltaX, double gestureDeltaY, 
    //ScrollEvent.HorizontalTextScrollUnits textDeltaXUnits, double textDeltaX, 
    //ScrollEvent.VerticalTextScrollUnits textDeltaYUnits, double textDeltaY, int touchCount)
    final ScrollEvent scrollEvent = new ScrollEvent(ScrollEvent.SCROLL,
            _x, _y, _screenX, _screenY,
            false, false, false, false,
            false, false, _scrollX, _scrollY, 0, 0,
            _scrollTextXUnits, _scrollTextX,
            _scrollTextYUnits, _scrollTextY, 0, null /* PickResult?*/);

    Point2D pointOnScene = node.localToScene(node.getLayoutBounds().getWidth() / 4, node.getLayoutBounds().getHeight() / 4);
    final PickResultChooser result = new PickResultChooser();
    scene.getRoot().impl_pickNode(new PickRay(pointOnScene.getX(), pointOnScene.getY()), result);
    Node nodeToSendEvent = result.getIntersectedNode();
    nodeToSendEvent.fireEvent(scrollEvent);
}

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