Wenn ich auf einen Path2D-Kreis in meinem JPanel klicke und diesen ziehe, wird die Größe geändert. Das Problem ist, dass der Kreis beim ersten Klicken und Ziehen auf eine kleinere Größe springt, die Größe jedoch beim Klicken und Ziehen korrekt geändert wird. Der einfachste Weg, dies zu demonstrieren, besteht darin, den folgenden ausführbaren Code auszuführen.

Ich weiß, ich muss diesen Code reparieren:

@Override
public void mouseDragged(MouseEvent e) {
    int mouseX = e.getX();
    int mouseY = e.getY();
    if (resizing) {
        System.out.println("resizing");
        Rectangle bounds = shapes.get(currentIndex).getBounds();
        int shapeX = bounds.x;
        int shapeY = bounds.y;
        shapes.get(currentIndex).reset();
        shapes.get(currentIndex).append(
                new Ellipse2D.Double(shapeX, shapeY, mouseX
                        - shapeX, mouseX - shapeX), true);
        repaint();
    }
}

Ich bin mir nicht sicherWi, obwohl. Ich klicke auf den äußeren Rand des Kreises und setze dann dasLänge und Breit der Grenzen des Kreises an der Stelle, an der sich der neue Mauspunkt befindet ... Was ich aber tun muss, ist der äußere Rand der Kreiskoordinaten zu den neuen Mauspunkten. Irgendwelche Ideen, wie man den richtigen Punkt berechnet?

Full Code

import java.awt.BasicStroke;
import java.awt.Color;
import java.awt.Cursor;
import java.awt.EventQueue;
import java.awt.Graphics;
import java.awt.Graphics2D;
import java.awt.Panel;
import java.awt.Point;
import java.awt.Rectangle;
import java.awt.event.MouseAdapter;
import java.awt.event.MouseEvent;
import java.awt.geom.Ellipse2D;
import java.awt.geom.Path2D;
import java.awt.geom.Point2D;
import java.awt.geom.Rectangle2D;
import java.util.ArrayList;
import java.util.List;
import javax.swing.JFrame;
import static javax.swing.JFrame.EXIT_ON_CLOSE;
import javax.swing.JPanel;
import javax.swing.UIManager;
import javax.swing.UnsupportedLookAndFeelException;

public class Editor {

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

    public Editor() {
        EventQueue.invokeLater(new Runnable() {
            @Override
            public void run() {
                try {
                    UIManager.setLookAndFeel(UIManager
                            .getSystemLookAndFeelClassName());
                } catch (ClassNotFoundException | InstantiationException
                        | IllegalAccessException
                        | UnsupportedLookAndFeelException ex) {
                    ex.printStackTrace();
                }

                JFrame frame = new UMLWindow();
                frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
                frame.setBounds(30, 30, 1000, 700);
                frame.getContentPane().setBackground(Color.white);
                frame.setVisible(true);
                frame.setLocationRelativeTo(null);
                frame.setVisible(true);
            }
        });
    }

    public static class UMLWindow extends JFrame {

        Shapes shapeList = new Shapes();
        Panel panel;

        private static final long serialVersionUID = 1L;

        public UMLWindow() {
            addMenus();
            panel = new Panel();
        }

        public void addMenus() {

            getContentPane().add(shapeList);

            setSize(300, 200);
            setLocationRelativeTo(null);
            setDefaultCloseOperation(EXIT_ON_CLOSE);

            shapeList.addCircle(100, 100);
        }
    }

    // Shapes class, used to draw the shapes on the panel
    // as well as implements the MouseListener for dragging
    public static class Shapes extends JPanel {

        private static final long serialVersionUID = 1L;

        private List<Path2D> shapes = new ArrayList<Path2D>();
        int currentIndex;

        private Point mousePoint;

        public Shapes() {
            MyMouseAdapter myMouseAdapter = new MyMouseAdapter();
            addMouseListener(myMouseAdapter);
            addMouseMotionListener(myMouseAdapter);
        }

        public void addCircle(int width, int height) {
            Path2D circ = new Path2D.Double();
            circ.append(new Ellipse2D.Double(442, 269, width, height), true);
            shapes.add(circ);
            repaint();
        }

        @Override
        protected void paintComponent(Graphics g) {
            super.paintComponent(g);

            Graphics2D g2 = (Graphics2D) g;
            g2.setStroke(new BasicStroke(2));
            for (Path2D shape : shapes) {
                g2.setColor(Color.BLACK);
                g2.draw(shape);
            }
        }

        public Rectangle2D getActiveBounds(float angel, Rectangle bounds) {

            Point2D p = getPointOnEdge(angel, bounds);

            return new Rectangle2D.Double(p.getX() - 4, p.getY() - 4, 8, 8);

        }

        public Point2D getPointOnEdge(float angel, Rectangle bounds) {

            float radius = Math.max(bounds.width, bounds.height) / 2;

            float x = radius;
            float y = radius;

            double rads = Math.toRadians((angel + 90));

            // Calculate the outter point of the line
            float xPosy = (float) (x + Math.cos(rads) * radius);
            float yPosy = (float) (y + Math.sin(rads) * radius);

            return new Point2D.Float(xPosy + bounds.x, yPosy + bounds.y);

        }

        class MyMouseAdapter extends MouseAdapter {
            Boolean hovering = false;
            Boolean resizing = true;

            @Override
            public void mouseMoved(MouseEvent e) {
                mousePoint = e.getPoint();
                for (int i = 0; i < shapes.size(); i++) {
                    Path2D shape = shapes.get(i);
                    Rectangle2D bottomRight = getActiveBounds(-45,
                            shape.getBounds());

                    if (mousePoint != null) {

                        if (bottomRight.contains(mousePoint)) {
                            Cursor cursor = Cursor
                                    .getPredefinedCursor(Cursor.SE_RESIZE_CURSOR);
                            setCursor(cursor);
                            hovering = true;
                        } else {
                            Cursor cursor = Cursor
                                    .getPredefinedCursor(Cursor.DEFAULT_CURSOR);
                            setCursor(cursor);
                            hovering = false;
                        }
                    }
                }

                repaint();
            }

            @Override
            public void mousePressed(MouseEvent e) {
                if (hovering) {
                    resizing = true;
                    System.out.println("Starting to resize");
                }
            }

            @Override
            public void mouseDragged(MouseEvent e) {
                int mouseX = e.getX();
                int mouseY = e.getY();
                if (resizing) {
                    System.out.println("resizing");
                    Rectangle bounds = shapes.get(currentIndex).getBounds();
                    int shapeX = bounds.x;
                    int shapeY = bounds.y;
                    shapes.get(currentIndex).reset();
                    shapes.get(currentIndex).append(
                            new Ellipse2D.Double(shapeX, shapeY, mouseX
                                    - shapeX, mouseX - shapeX), true);
                    repaint();
                }
            }

            @Override
            public void mouseReleased(MouseEvent e) {
                if (resizing) {
                    System.out.println("Done resizing");
                    resizing = false;
                }
            }

        }
    }

}