Java tutorial
/* =========================================================== * JFreeChart : a free chart library for the Java(tm) platform * =========================================================== * * (C) Copyright 2000-2014, by Object Refinery Limited and Contributors. * * Project Info: http://www.jfree.org/jfreechart/index.html * * This library is free software; you can redistribute it and/or modify it * under the terms of the GNU Lesser General Public License as published by * the Free Software Foundation; either version 2.1 of the License, or * (at your option) any later version. * * This library is distributed in the hope that it will be useful, but * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY * or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public * License for more details. * * You should have received a copy of the GNU Lesser General Public * License along with this library; if not, write to the Free Software * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, * USA. * * [Java is a trademark or registered trademark of Sun Microsystems, Inc. * in the United States and other countries.] * * ----------------------------- * FreePathSelectionHandler.java * ----------------------------- * (C) Copyright 2013, 2014, by Michael Zinsmaier and Contributors. * * Original Author: Michael Zinsmaier; * Contributor(s): David Gilbert (for Object Refinery Limited); * * Changes: * -------- * 17-Sep-2013 : Version 1 from MZ (DG); * */ package org.jfree.chart.panel.selectionhandler; import java.awt.Color; import java.awt.Paint; import java.awt.Point; import java.awt.Stroke; import java.awt.event.MouseEvent; import java.awt.geom.GeneralPath; import java.awt.geom.Point2D; import java.awt.geom.Rectangle2D; import java.util.ArrayList; import java.util.List; import org.jfree.chart.ChartPanel; import org.jfree.chart.util.ShapeUtils; /** * A mouse handler that allows data items to be selected. The selection path * can be freely manipulated by dragging the mouse away from the starting * point. This selection handler is intended for intersection based selection. * * Will only work together with a ChartPanel as event source */ public class FreePathSelectionHandler extends RegionSelectionHandler { /** a generated serial id. */ private static final long serialVersionUID = 8051992918085934799L; /** * temporary storage for points */ private List<Point> points; /** * The selection path (in Java2D space). */ private GeneralPath selectionPath; /** * The start mouse point. */ private Point2D lastPoint; /** * Creates a new default instance. */ public FreePathSelectionHandler() { this.selectionPath = new GeneralPath(); this.lastPoint = null; this.points = new ArrayList<Point>(); setFillPaint(Color.GRAY); setOutlinePaint(new Color(0, 160, 230)); } /** * Creates a new instance with a modifier restriction * @param modifier e.g. shift has to be pressed InputEvents.SHIFT_MASK */ public FreePathSelectionHandler(int modifier) { super(modifier); this.selectionPath = new GeneralPath(); this.lastPoint = null; this.points = new ArrayList<Point>(); setFillPaint(Color.GRAY); setOutlinePaint(new Color(0, 160, 230)); } /** * Creates a new selection handler with the specified attributes. * * @param outlineStroke the outline stroke. * @param outlinePaint the outline paint. * @param fillPaint the fill paint. */ public FreePathSelectionHandler(Stroke outlineStroke, Paint outlinePaint, Paint fillPaint) { super(outlineStroke, outlinePaint, fillPaint); this.selectionPath = new GeneralPath(); this.lastPoint = null; this.points = new ArrayList<Point>(); } /** * starts the selection by fixing the start point of the selection path * * @param e the event. */ public void mousePressed(MouseEvent e) { if (!(e.getSource() instanceof ChartPanel)) { return; } ChartPanel panel = (ChartPanel) e.getSource(); Rectangle2D dataArea = panel.getScreenDataArea(); if (dataArea.contains(e.getPoint())) { SelectionManager selectionManager = panel.getSelectionManager(); if (selectionManager != null) { if (!e.isShiftDown()) { selectionManager.clearSelection(); } Point pt = e.getPoint(); this.lastPoint = new Point(pt); this.points.add(pt); } } } /** * adjusts the selection by adding a new line segment from the last to the * actual position * * @param e the event. */ public void mouseDragged(MouseEvent e) { ChartPanel panel = (ChartPanel) e.getSource(); if (this.lastPoint == null) { panel.clearLiveMouseHandler(); return; // we never started a selection } Point pt = e.getPoint(); Point2D pt2 = ShapeUtils.getPointInRectangle(pt.x, pt.y, panel.getScreenDataArea()); if (pt2.distance(this.lastPoint) > 5) { this.points.add(new Point((int) pt2.getX(), (int) pt2.getY())); this.lastPoint = pt2; } selectionPath = createPathFromPoints(this.points); panel.setSelectionShape(selectionPath); panel.setSelectionFillPaint(this.fillPaint); panel.setSelectionOutlinePaint(this.outlinePaint); panel.repaint(); } /** * finishes the selection and calls the {@link SelectionManager} of * the event source. The SelectionManager is then responsible for the processing * of the geometric selection. */ public void mouseReleased(MouseEvent e) { ChartPanel panel = (ChartPanel) e.getSource(); if (this.lastPoint == null) { panel.clearLiveMouseHandler(); return; // we never started a selection } this.selectionPath = createPathFromPoints(this.points); this.selectionPath.closePath(); SelectionManager selectionManager = panel.getSelectionManager(); // do something with the selection shape if (selectionManager != null) { selectionManager.select(this.selectionPath); } panel.setSelectionShape(null); this.selectionPath.reset(); this.points.clear(); this.lastPoint = null; panel.repaint(); panel.clearLiveMouseHandler(); } /** * creates a line shape from a series of points * * @param points * @return the line shape */ private GeneralPath createPathFromPoints(List<Point> points) { GeneralPath path = new GeneralPath(); if (points.size() > 0) { Point p = points.get(0); path.moveTo(p.getX(), p.getY()); } for (int i = 1; i < points.size(); i++) { Point p = points.get(i); path.lineTo((p.getX() - 1), (p.getY() + 1)); path.lineTo((p.getX() + 1), (p.getY() + 1)); } for (int i = (points.size() - 1); i >= 0; i--) { Point p = points.get(i); path.lineTo((p.getX() + 1), (p.getY() - 1)); path.lineTo((p.getX() - 1), (p.getY() - 1)); } return path; } }