source: josm/trunk/src/org/openstreetmap/josm/gui/MapSlider.java@ 627

// License: GPL. Copyright 2007 by Immanuel Scholz and others
package org.openstreetmap.josm.gui;

import java.awt.event.MouseAdapter;
import java.awt.event.MouseEvent;
import java.beans.PropertyChangeEvent;
import java.beans.PropertyChangeListener;

import javax.swing.JSlider;
import javax.swing.event.ChangeEvent;
import javax.swing.event.ChangeListener;

import org.openstreetmap.josm.actions.HelpAction.Helpful;
import org.openstreetmap.josm.data.coor.EastNorth;

class MapSlider extends JSlider implements PropertyChangeListener, ChangeListener, Helpful {
        
    private final MapView mv;
        boolean clicked = false;
        
        public MapSlider(MapView mv) {
                super(0, 20);
                setOpaque(false);
                this.mv = mv;
                addMouseListener(new MouseAdapter(){
                        @Override public void mousePressed(MouseEvent e) {
                                clicked = true;
                        }
                        @Override public void mouseReleased(MouseEvent e) {
                                clicked = false;
                        }
                });
                mv.addPropertyChangeListener("scale", this);
                addChangeListener(this);
        }
        
        public void propertyChange(PropertyChangeEvent evt) {
                if (!getModel().getValueIsAdjusting())
                        setValue(this.mv.zoom());
        }
        
        public void stateChanged(ChangeEvent e) {
                if (!clicked)
                        return;
                EastNorth pos = MapView.world;
                for (int zoom = 0; zoom < getValue(); ++zoom)
                        pos = new EastNorth(pos.east()/2, pos.north()/2);
                if (this.mv.getWidth() < this.mv.getHeight())
                        this.mv.zoomTo(this.mv.center, pos.east()*2/(this.mv.getWidth()-20));
                else
                        this.mv.zoomTo(this.mv.center, pos.north()*2/(this.mv.getHeight()-20));
        }

        public String helpTopic() {
            return "MapView/Slider";
    }
}