PanMouseInputListener.java

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

import java.awt.Cursor;
import java.awt.Point;
import java.awt.event.MouseEvent;
import java.awt.geom.Point2D;

import javax.swing.SwingUtilities;
import javax.swing.event.MouseInputAdapter;

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

/**
 * Used to pan using press and drag mouse gestures
 * @author joshy
 */
public class PanMouseInputListener extends MouseInputAdapter
{
	private Point prev;
	private JXMapViewer viewer;
	
	/**
	 * @param viewer the jxmapviewer
	 */
	public PanMouseInputListener(JXMapViewer viewer)
	{
		this.viewer = viewer;
	}

	@Override
	public void mousePressed(MouseEvent evt)
	{
		prev = evt.getPoint();
	}

	@Override
	public void mouseDragged(MouseEvent evt)
	{
		if (!SwingUtilities.isLeftMouseButton(evt))
			return;

		Point current = evt.getPoint();
		double x = viewer.getCenter().getX() - (current.x - prev.x);
		double y = viewer.getCenter().getY() - (current.y - prev.y);

		if (!viewer.isNegativeYAllowed())
		{
			if (y < 0)
			{
				y = 0;
			}
		}

		int maxHeight = (int) (viewer.getTileFactory().getMapSize(viewer.getZoom()).getHeight() * viewer
				.getTileFactory().getTileSize(viewer.getZoom()));
		if (y > maxHeight)
		{
			y = maxHeight;
		}

		prev = current;
		viewer.setCenter(new Point2D.Double(x, y));
		viewer.repaint();
		viewer.setCursor(Cursor.getPredefinedCursor(Cursor.MOVE_CURSOR));
	}

	@Override
	public void mouseReleased(MouseEvent evt)
	{
		if (!SwingUtilities.isLeftMouseButton(evt))
			return;

		prev = null;
		viewer.setCursor(Cursor.getPredefinedCursor(Cursor.DEFAULT_CURSOR));
	}

	@Override
	public void mouseEntered(MouseEvent e)
	{
		SwingUtilities.invokeLater(new Runnable()
		{
			@Override
			public void run()
			{
				viewer.requestFocusInWindow();
			}
		});
	}
}