CenterMapListener.java

package com.opendoorlogistics.codefromweb.jxmapviewer2.fork.swingx.input;

import java.awt.Rectangle;
import java.awt.event.MouseAdapter;
import java.awt.event.MouseEvent;
import java.awt.geom.Point2D;

import javax.swing.SwingUtilities;

import com.opendoorlogistics.codefromweb.jxmapviewer2.fork.swingx.JXMapViewer;

/**
 * Centers the map on the mouse cursor
 * if left is double-clicked or middle mouse
 * button is pressed.
 * @author Martin Steiger
 * @author joshy
 */
public class CenterMapListener extends MouseAdapter
{
	private JXMapViewer viewer;
	
	/**
	 * @param viewer the jxmapviewer
	 */
	public CenterMapListener(JXMapViewer viewer)
	{
		this.viewer = viewer;
	}

	@Override
	public void mousePressed(MouseEvent evt)
	{
		boolean left = SwingUtilities.isLeftMouseButton(evt);
		boolean middle = SwingUtilities.isMiddleMouseButton(evt);
		boolean doubleClick = (evt.getClickCount() == 2);

		if (middle || (left && doubleClick))
		{
			recenterMap(evt);
		}
	}
	
	private void recenterMap(MouseEvent evt)
	{
		Rectangle bounds = viewer.getViewportBounds();
		double x = bounds.getX() + evt.getX();
		double y = bounds.getY() + evt.getY();
		viewer.setCenter(new Point2D.Double(x, y));
                viewer.setZoom(viewer.getZoom() - 1);
		viewer.repaint();
	}
}