Question

我在拖动鼠标时使用此代码绘制矩形。问题是我只能从左到右画画。

这是我的代码：

public class functionalTest extends Application {

    BorderPane pane;
    Rectangle rect;
    Group group;
    SimpleDoubleProperty rectinitX = new SimpleDoubleProperty();
    SimpleDoubleProperty rectinitY = new SimpleDoubleProperty();
    SimpleDoubleProperty rectX = new SimpleDoubleProperty();
    SimpleDoubleProperty rectY = new SimpleDoubleProperty();


    @Override
    public void start(Stage stage) {


        pane = new BorderPane();
        Scene scene = new Scene(pane, 800, 600);
        stage.setScene(scene);

        group = new Group();
        Circle circle = new Circle(200, 200, 25);
        circle.setFill(Color.HOTPINK);
        group.getChildren().add(circle);

        scene.setOnMouseDragged(mouseHandler);
        scene.setOnMousePressed(mouseHandler);
        scene.setOnMouseReleased(mouseHandler);

        rect = getNewRectangle();
        rect.widthProperty().bind(rectX.subtract(rectinitX));
        rect.heightProperty().bind(rectY.subtract(rectinitY));
        pane.getChildren().add(rect);
        pane.getChildren().add(group);
        stage.show();

        ArrayList<Node> containedNodesArray = new ArrayList<Node>();
        containedNodesArray = Main.dragBoxSelection(group, rect);

        if (containedNodesArray.size() > 0) {
            System.out.println("Success");
        }
    }

    EventHandler<MouseEvent> mouseHandler = new EventHandler<MouseEvent>() {

        @Override
        public void handle(MouseEvent mouseEvent) {

            if (mouseEvent.getEventType() == MouseEvent.MOUSE_PRESSED) {
                rect.setX(mouseEvent.getX());
                rect.setY(mouseEvent.getY());
                rectinitX.set(mouseEvent.getX());
                rectinitY.set(mouseEvent.getY());
            } else if (mouseEvent.getEventType() == MouseEvent.MOUSE_DRAGGED) {
                rectX.set(mouseEvent.getX());
                rectY.set(mouseEvent.getY());
                System.out.println("RECTX"+rectX.getValue());
                System.out.println("RECTY"+rectY.getValue());
                ArrayList<Node> containedNodesArray = new ArrayList<Node>();
                containedNodesArray = Main.dragBoxSelection(group, rect);

                if (containedNodesArray.size() > 0) {
                    System.out.println("Success");
                }
            } else if (mouseEvent.getEventType() == MouseEvent.MOUSE_RELEASED) {
                // Clone the rectangle
                Rectangle r = getNewRectangle();
                r.setX(rect.getX());
                r.setY(rect.getY());
                r.setWidth(rect.getWidth());
                r.setHeight(rect.getHeight());
                pane.getChildren().add(r);

                // Hide the rectangle
                rectX.set(0);
                rectY.set(0);
            }
        }


    };

    private Rectangle getNewRectangle() {
        Rectangle r = new Rectangle();
        r.setFill(Color.web("blue", 0.1));
        r.setStroke(Color.BLUE);

        return r;
    }

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

任何人都可以帮助我从右到左绘制其他方向，左右向左到左边。

Answer 1

这是你需要做的：

拖动鼠标时：获取dx = mouseEvent.getX() - initial X;如果dx < 0，那么您需要setTranslateX(dx)和setWidth(-dx) 其他setTranslateX(0)和setWidth(dx)

对Y坐标执行相同操作，但这次使用的是高度而不是宽度;

这就是全部。

Answer 2

我将代码更换为： EventHandler mouseHandler = new EventHandler（）{

    @Override
    public void handle(MouseEvent mouseEvent) {

        if (mouseEvent.getEventType() == MouseEvent.MOUSE_PRESSED) {
            rectinitX.set(mouseEvent.getX());
            rectinitY.set(mouseEvent.getY());
        } else if (mouseEvent.getEventType() == MouseEvent.MOUSE_DRAGGED) {
            Double width = mouseEvent.getX() - rectinitX.getValue();
            if (width < 0) {
                rectX.set(mouseEvent.getX());
                rect.setTranslateX(width);
                rect.widthProperty().bind(rectinitX.subtract(rectX));
                System.out.println(rect.getWidth());
            } else {
                rectX.set(mouseEvent.getX());
                rect.setTranslateX(0);
                rect.widthProperty().bind(rectX.subtract(rectinitX));
            }

        } else if (mouseEvent.getEventType() == MouseEvent.MOUSE_RELEASED) {
            // Clone the rectangle
            Rectangle r = getNewRectangle();
            r.setX(rect.getX());
            r.setY(rect.getY());
            r.setWidth(rect.getWidth());
            r.setHeight(rect.getHeight());
            pane.getChildren().add(r);


        }
    }
};

我只是想首先尝试宽度值的解决方案，但它似乎不起作用。你对我的实施有什么意见吗？

Answer 3

您缺少高度参数。

            if (event.getEventType() == MouseEvent.MOUSE_PRESSED) {
            rect.setX(event.getX());
            rect.setY(event.getY());
            rectinitX.set(event.getX());
            rectinitY.set(event.getY());
        } else if (event.getEventType() == MouseEvent.MOUSE_DRAGGED) {
            Double dx = event.getX() - rectinitX.getValue();
            Double dy = event.getY() - rectinitY.getValue();
            if (dx < 0) {
                rectX.set(event.getX());
                rect.setTranslateX(dx);
                rect.widthProperty().bind(rectinitX.subtract(rectX));
            } else {
                rectX.set(event.getX());
                rect.setTranslateX(0);
                rect.widthProperty().bind(rectX.subtract(rectinitX));
            }
            if(dy < 0) {
                rectY.set(event.getY());
                rect.setTranslateY(dy);
                rect.heightProperty().bind(rectinitX.subtract(rectX));
            } else {
                rectY.set(event.getY());
                rect.setTranslateY(0);
                rect.heightProperty().bind(rectY.subtract(rectinitY));
            }

        } else if (event.getEventType() == MouseEvent.MOUSE_RELEASED) {
            // Clone the rectangle
            Rectangle r = getNewRectangle();
            r.setX(rect.getX());
            r.setY(rect.getY());
            r.setWidth(rect.getWidth());
            r.setHeight(rect.getHeight());
            pane.getChildren().add(r);

            // Hide the rectangle
            rectX.set(0);
            rectY.set(0);
  }}}};

这是在不同方向绘制的确切代码，但不幸的是从左下到右顶部工作，我无法弄明白。在默认情况下从左到右完美地工作，但从右到左绘制时存在代码错误。如果有人能够弄清楚，我会被大肆宣传

Answer 4

应该阅读

 if(dy < 0)
 {
   rectY.set(mouseEvent.getY());
   rect.setTranslateY(dy);
   rect.heightProperty().bind(rectinitY.subtract(rectY));
 }

Answer 5

不知道它是否对任何人都有效，但对我来说却没有运气。但是，这在JavaFX 8中确实对我有用：

if( event.getEventType() == MouseDragEvent.MOUSE_DRRAGGED ) {
    double deltaX = event.getX() - initialPt.getX();
    double deltaY = event.getY() - initialPt.getY();

    if( deltaX < 0 ) {
        rect.setX( event.getX() );
        rect.setWidth( -deltaX );
    }
    else {
        rect.setX( initialPt.getX() );
        rect.setWidth( event.getX() - initialPt.getX() );
    }

    if( deltaY < 0 ) {
        rect.setY( event.getY() );
        rect.setHeight( -deltaY );
    }
    else {
        rect.setY( initialPt.getY() );
        rect.setHeight( event.getY() - initialPt.getY() );
    }
}

无需致电setTranslateX()或setTranslateY()。不知道这是否与您使用的FX版本有关。

使用javaFX在所有方向上绘制矩形失败

5 个答案: