Question

来源：

    flowLine = new Line();
    flowLine.setStrokeWidth(3);
    flowLine.setStroke(Color.RED);
    flowGroup.getChildren().addAll(flowLine);

    targetNodeItem.setOnMousePressed(new EventHandler<MouseEvent>() {
        @Override
        public void handle(MouseEvent mEvent) {

            drawPoint = new Point2D(mEvent.getSceneX(), mEvent.getSceneY());
            startX = drawPoint.getX();
            startY = drawPoint.getY();
        }           
    });

    targetNodeItem.setOnMouseDragged(new EventHandler<MouseEvent>() {
        @Override
        public void handle(MouseEvent mEvent) {

            flowLine.setStartX(startX);
            flowLine.setStartY(startY);
            flowLine.setEndX(mEvent.getSceneX());
            flowLine.setEndY(mEvent.getSceneY());
        }
    });

targetNodeItem是节点。

我想从该节点拖动并生成FlowLine，但生成为图像（http://2url.kr/2lfjlsfa）的FlowLine坐标不正确。

=============================================== ===================================

检查一下 - ＆gt;＆gt;＆gt; http://youtu.be/iZOL0Fs-umk

请帮助我

Answer 1

你的代码让我在没有坐标问题的情况下绘制一条线......

我用过：

public class MouseDrag extends Application
{
    private Point2D drawPoint;
    private double startX;
    private double startY;

    @Override
    public void start(Stage primaryStage) throws Exception
    {
        Pane root = new Pane();
        Scene scene = new Scene(root, 200, 200);

        Group flowGroup = new Group();        
        final Line line = new Line();
        line.setStrokeWidth(3);
        line.setStroke(Color.RED);

        Label nodeOne = new Label("One");
        nodeOne.setOnMousePressed((event) ->
        {
            drawPoint = new Point2D(event.getSceneX(), event.getSceneY());
            startX = drawPoint.getX();
            startY = drawPoint.getY();
            line.setStartX(startX);
            line.setStartY(startY);

        });

        nodeOne.setOnMouseDragged((event) ->
        {
            line.setEndX(event.getSceneX());
            line.setEndY(event.getSceneY());

            System.out.println("X/Y: " + event.getSceneX() + "/" + event.getSceneY());
        });

        Label nodeTwo = new Label("Two");
        nodeTwo.setLayoutX(100);
        nodeTwo.setLayoutY(100);

        flowGroup.getChildren().addAll(nodeOne, nodeTwo, line);
        root.getChildren().addAll(flowGroup);

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

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

Answer 2

JavaFX 8 MouseEvent API

请注意，您可以从MouseEvent中提取多个X和Y值。在这种情况下，您正在使用getSceneX()和getSceneY()，它会为您提供相对于包含Scene的坐标。

另外：＆＃34; MouseDragged＆＃34;被多次调用，这会对setStartX(...) + setStartY(...)产生大量不必要的调用。考虑将其移动到＆＃34; MousePressed＆＃34;，只调用一次（见下文）。 HTH

targetNodeItem.setOnMousePressed(new EventHandler<MouseEvent>() {
    @Override
    public void handle(MouseEvent mEvent) {
        flowLine.setStartX(mEvent.getX());
        flowLine.setStartY(mEvent.getY());
    }           
});

targetNodeItem.setOnMouseDragged(new EventHandler<MouseEvent>() {
    @Override
    public void handle(MouseEvent mEvent) {
        //System.out.println("X: " + mEvent.getX() + " Y: " + mEvent.getY());
        flowLine.setEndX(mEvent.getX());
        flowLine.setEndY(mEvent.getY());
    }
});

如何将MouseEvent的局部坐标转换为MouseEvent的场景坐标？在JAVAFX

2 个答案: