source: osm/applications/editors/josm/plugins/slippy_map_chooser/src/OsmMapControl.java@ 9537

// This code has been adapted and copied from code that has been written by Immanuel Scholz and others for JOSM.
// License: GPL. Copyright 2007 by Tim Haussmann

import java.awt.Point;
import java.awt.event.KeyEvent;
import java.awt.event.MouseAdapter;
import java.awt.event.MouseEvent;
import java.awt.event.MouseListener;
import java.awt.event.MouseMotionListener;

import javax.swing.JComponent;
import javax.swing.JPanel;
import javax.swing.KeyStroke;

/**
 * This class controls the user input by listening to mouse and key events.
 * Currently implemented is: - zooming in and out with scrollwheel - zooming in
 * and centering by double clicking - selecting an area by clicking and dragging
 * the mouse
 * 
 * @author Tim Haussmann
 */
public class OsmMapControl extends MouseAdapter implements MouseMotionListener, MouseListener {

        // start and end point of selection rectangle
        private Point iStartSelectionPoint;
        private Point iEndSelectionPoint;

        // the SlippyMapChooserComponent
        private final SlippyMapChooser iSlippyMapChooser;

        private SizeButton iSizeButton = null;

        /**
         * Create a new OsmMapControl
         */
        public OsmMapControl(SlippyMapChooser navComp, JPanel contentPane, SizeButton sizeButton) {
                this.iSlippyMapChooser = navComp;
                iSlippyMapChooser.addMouseListener(this);
                iSlippyMapChooser.addMouseMotionListener(this);

                String[] n = { ",", ".", "up", "right", "down", "left" };
                int[] k =
                                { KeyEvent.VK_COMMA, KeyEvent.VK_PERIOD, KeyEvent.VK_UP, KeyEvent.VK_RIGHT,
                                                KeyEvent.VK_DOWN, KeyEvent.VK_LEFT };

                if (contentPane != null) {
                        for (int i = 0; i < n.length; ++i) {
                                contentPane.getInputMap(JComponent.WHEN_IN_FOCUSED_WINDOW).put(
                                                KeyStroke.getKeyStroke(k[i], KeyEvent.CTRL_DOWN_MASK),
                                                "MapMover.Zoomer." + n[i]);
                        }
                }
                iSizeButton = sizeButton;
        }

        /**
         * Start drawing the selection rectangle if it was the 1st button (left
         * button)
         */
        @Override
        public void mousePressed(MouseEvent e) {
                if (e.getButton() == MouseEvent.BUTTON1) {
                        if (!iSizeButton.hit(e.getPoint())) {
                                iStartSelectionPoint = e.getPoint();
                                iEndSelectionPoint = e.getPoint();
                        }
                }
        }

        @Override
        public void mouseDragged(MouseEvent e) {
                if (iStartSelectionPoint != null) {
                        iEndSelectionPoint = e.getPoint();
                        iSlippyMapChooser.setSelection(iStartSelectionPoint, iEndSelectionPoint);
                }
        }

        /**
         * When dragging the map change the cursor back to it's pre-move cursor. If
         * a double-click occurs center and zoom the map on the clicked location.
         */
        @Override
        public void mouseReleased(MouseEvent e) {
                if (e.getButton() == MouseEvent.BUTTON1) {
                        if (iSizeButton.hit(e.getPoint())) {
                                iSizeButton.toggle();
                                iSlippyMapChooser.resizeSlippyMap();
                        } else {
                                if (e.getClickCount() == 1) {
                                        iSlippyMapChooser.setSelection(iStartSelectionPoint, e.getPoint());

                                        // reset the selections start and end
                                        iEndSelectionPoint = null;
                                        iStartSelectionPoint = null;
                                }
                        }
                }
        }

}