scaledisplaylayer.java

openmap java写的开源数字地图程序. 用applet实现,可以像google map 那样放大缩小地图.

/* **********************************************************************
 *
 *  ROLANDS & ASSOCIATES Corporation
 *  500 Sloat Avenue
 *  Monterey, CA 93940
 *  [phone]
 *
 *  Copyright (C) 2002, 2003 ROLANDS & ASSOCIATES Corporation. All rights reserved.
 *  Openmap is a trademark of BBN Technologies, A Verizon Company
 *
 *
 * **********************************************************************
 *
 * $Source: /cvs/distapps/openmap/src/openmap/com/bbn/openmap/layer/ScaleDisplayLayer.java,v $
 * $Revision: 1.6.2.2 $
 * $Date: 2005/08/09 19:21:28 $
 * $Author: dietrick $
 *
 * **********************************************************************
 */

package com.bbn.openmap.layer;

import java.beans.PropertyVetoException;
import java.util.Properties;

import javax.swing.JPanel;
import javax.swing.JRadioButton;

import com.bbn.openmap.LatLonPoint;
import com.bbn.openmap.omGraphics.OMGraphicList;
import com.bbn.openmap.omGraphics.OMLine;
import com.bbn.openmap.omGraphics.OMText;
import com.bbn.openmap.proj.GreatCircle;
import com.bbn.openmap.proj.Length;
import com.bbn.openmap.proj.Projection;
import com.bbn.openmap.util.PropUtils;

/**
 * Layer objects are components which can be added to the MapBean to
 * make a map.
 * <p>
 * Layers implement the ProjectionListener interface to listen for
 * ProjectionEvents. When the projection changes, they may need to
 * refetch, regenerate their graphics, and then repaint themselves
 * into the new view.
 * <p>
 * ### Layer used by the overview handler <br>
 * scaleLayer.class=com.rolands.jtlsweb.map.layer.ScaleDisplayLayer
 * <br>
 * scaleLayer.prettyName=Scale <br>
 * scaleLayer.lineColor=ff777777 <br>
 * scaleLayer.textColor=ff000000 <br>
 * scaleLayer.unitOfMeasure=nm <br>
 * scaleLayer.locationXoffset=-10 <br>
 * scaleLayer.locationYoffset=-20 <br>
 * scaleLayer.width=150 <br>
 * scaleLayer.height=10 <br>
 * <br>
 * unitOfMeasure - any com.bbn.openmap.proj.Length instance returned
 * by Length.get(string). <br>
 * locationXoffset - offset in pixels from left/right, positive from
 * left edge, negative from right edge <br>
 * locationYoffset - offset in pixels from top/bottom, positive from
 * top edge, negative from bottom edge <br>
 * width - width of scale indidator bar in pixels <br>
 * height - height of scale indidator bar in pixels <br>
 * <br>
 */
public class ScaleDisplayLayer extends OMGraphicHandlerLayer {

    public ScaleDisplayLayer() {
        super();
        setProjectionChangePolicy(new com.bbn.openmap.layer.policy.ListResetPCPolicy(this));
    }

    // Color variables for different line types
    protected java.awt.Color lineColor = null;
    protected java.awt.Color textColor = null;

    // Default colors to use, if not specified in the properties.
    protected String defaultLineColorString = "FFFFFF";
    protected String defaultTextColorString = "FFFFFF";
    protected String defaultUnitOfMeasureString = "km";
    protected int defaultLocationXoffset = -10;
    protected int defaultLocationYoffset = -10;
    protected int defaultWidth = 150;
    protected int defaultHeight = 10;

    // property text values
    public static final String LineColorProperty = "lineColor";
    public static final String TextColorProperty = "textColor";
    public static final String UnitOfMeasureProperty = "unitOfMeasure";
    public static final String LocationXOffsetProperty = "locationXoffset";
    public static final String LocationYOffsetProperty = "locationYoffset";
    public static final String WidthProperty = "width";
    public static final String HeightProperty = "height";

    protected String unitOfMeasure = null;
    protected Length uom = Length.get(defaultUnitOfMeasureString);
    protected String uomAbbr = uom.getAbbr();
    protected int locationXoffset = defaultLocationXoffset;
    protected int locationYoffset = defaultLocationYoffset;
    protected int width = defaultWidth;
    protected int height = defaultHeight;

    /**
     * Sets the properties for the <code>Layer</code>. This allows
     * <code>Layer</code> s to get a richer set of parameters than
     * the <code>setArgs</code> method.
     * 
     * @param prefix the token to prefix the property names
     * @param properties the <code>Properties</code> object
     */
    public void setProperties(String prefix, Properties properties) {
        super.setProperties(prefix, properties);
        prefix = com.bbn.openmap.util.PropUtils.getScopedPropertyPrefix(prefix);

        lineColor = PropUtils.parseColorFromProperties(properties, prefix
                + LineColorProperty, defaultLineColorString);

        textColor = PropUtils.parseColorFromProperties(properties, prefix
                + TextColorProperty, defaultTextColorString);

        String unitOfMeasure = properties.getProperty(prefix
                + UnitOfMeasureProperty);
        setUnitOfMeasure(unitOfMeasure);

        locationXoffset = PropUtils.intFromProperties(properties, prefix
                + LocationXOffsetProperty, defaultLocationXoffset);

        locationYoffset = PropUtils.intFromProperties(properties, prefix
                + LocationYOffsetProperty, defaultLocationYoffset);

        width = PropUtils.intFromProperties(properties,
                prefix + WidthProperty,
                defaultWidth);

        height = PropUtils.intFromProperties(properties, prefix
                + HeightProperty, defaultHeight);
    }

    public synchronized OMGraphicList prepare() {
        int w, h, left_x = 0, right_x = 0, lower_y = 0, upper_y = 0;
        Projection projection = getProjection();
        OMGraphicList graphics = new OMGraphicList();

        w = projection.getWidth();
        h = projection.getHeight();
        if (locationXoffset < 0) {
            left_x = w + locationXoffset - width;
            right_x = w + locationXoffset;
        } else if (locationXoffset >= 0) {
            left_x = locationXoffset;
            right_x = locationXoffset + width;
        }
        if (locationYoffset < 0) {
            upper_y = h + locationYoffset - height;
            lower_y = h + locationYoffset;
        } else if (locationYoffset >= 0) {
            upper_y = locationYoffset;
            lower_y = locationYoffset + height;
        }

        graphics.clear();

        OMLine line = new OMLine(left_x, lower_y, right_x, lower_y);
        line.setLinePaint(lineColor);
        graphics.add(line);

        line = new OMLine(left_x, lower_y, left_x, upper_y);
        line.setLinePaint(lineColor);
        graphics.add(line);

        line = new OMLine(right_x, lower_y, right_x, upper_y);
        line.setLinePaint(lineColor);
        graphics.add(line);

        LatLonPoint loc1 = projection.inverse(left_x, lower_y);
        LatLonPoint loc2 = projection.inverse(right_x, lower_y);

        float dist = GreatCircle.spherical_distance(loc1.radlat_,
                loc1.radlon_,
                loc2.radlat_,
                loc2.radlon_);
        dist = uom.fromRadians(dist);

        if (dist > 1)
            dist = (int) dist;
        String outtext = dist + " " + uomAbbr;

        OMText text = new OMText((left_x + right_x) / 2, lower_y - 3, ""
                + outtext, OMText.JUSTIFY_CENTER);
        text.setLinePaint(textColor);
        graphics.add(text);
        graphics.generate(projection);

        return graphics;
    }

    /**
     * Getter for property unitOfMeasure.
     * 
     * @return Value of property unitOfMeasure.
     */
    public String getUnitOfMeasure() {
        return this.unitOfMeasure;
    }

    /**
     * Setter for property unitOfMeasure.
     * 
     * @param unitOfMeasure New value of property unitOfMeasure.
     * 
     * @throws PropertyVetoException
     */
    public void setUnitOfMeasure(String unitOfMeasure) {
        if (unitOfMeasure == null)
            unitOfMeasure = Length.KM.toString();
        this.unitOfMeasure = unitOfMeasure;

        //There is a bug in the Length.get() method that will not
        // return
        //the correct (or any value) for a requested uom.
        //This does not work:
        //uom = com.bbn.openmap.proj.Length.get(unitOfMeasure);

        //Therefore, The following code correctly obtains the proper
        // Length object.

        Length[] choices = Length.getAvailable();
        uom = null;
        for (int i = 0; i < choices.length; i++) {
            if (unitOfMeasure.equalsIgnoreCase(choices[i].toString())
                    || unitOfMeasure.equalsIgnoreCase(choices[i].getAbbr())) {
                uom = choices[i];
                break;
            }
        }

        // of no uom is found assign Kilometers as the default.
        if (uom == null)
            uom = Length.KM;

        uomAbbr = uom.getAbbr();

    }

    javax.swing.Box palette;
    JRadioButton meterRadioButton;
    JRadioButton kmRadioButton;
    JRadioButton nmRadioButton;
    JRadioButton mileRadioButton;
    javax.swing.ButtonGroup uomButtonGroup;

    private JPanel jPanel3;
    private JPanel jPanel2;
    private JPanel jPanel1;

    /** Creates the interface palette. */
    public java.awt.Component getGUI() {

        if (palette == null) {
            if (com.bbn.openmap.util.Debug.debugging("graticule"))
                com.bbn.openmap.util.Debug.output("GraticuleLayer: creating Graticule Palette.");

            palette = javax.swing.Box.createVerticalBox();
            uomButtonGroup = new javax.swing.ButtonGroup();
            jPanel1 = new JPanel();
            jPanel2 = new JPanel();
            jPanel3 = new JPanel();
            kmRadioButton = new JRadioButton();
            meterRadioButton = new JRadioButton();
            nmRadioButton = new JRadioButton();
            mileRadioButton = new JRadioButton();

            jPanel1.setLayout(new javax.swing.BoxLayout(jPanel1, javax.swing.BoxLayout.Y_AXIS));

            jPanel2.setBorder(new javax.swing.border.TitledBorder("Unit Of Measure"));
            kmRadioButton.setText("KM");
            kmRadioButton.setToolTipText("Kilometers");
            uomButtonGroup.add(kmRadioButton);
            jPanel3.add(kmRadioButton);

            meterRadioButton.setText("M");
            meterRadioButton.setToolTipText("Meters");
            uomButtonGroup.add(meterRadioButton);
            jPanel3.add(meterRadioButton);

            nmRadioButton.setText("NM");
            nmRadioButton.setToolTipText("Nautical Miles");
            uomButtonGroup.add(nmRadioButton);
            jPanel3.add(nmRadioButton);

            mileRadioButton.setText("Mile");
            mileRadioButton.setToolTipText("Statute Miles");
            uomButtonGroup.add(mileRadioButton);
            jPanel3.add(mileRadioButton);

            jPanel2.add(jPanel3);

            jPanel1.add(jPanel2);

            palette.add(jPanel1);

            java.awt.event.ActionListener al = new java.awt.event.ActionListener() {
                public void actionPerformed(java.awt.event.ActionEvent e) {
                    String ac = e.getActionCommand();

                    if (ac.equalsIgnoreCase(UnitOfMeasureProperty)) {
                        JRadioButton jrb = (JRadioButton) e.getSource();
                        setUnitOfMeasure(jrb.getText());
                        doPrepare();
                    } else {
                        com.bbn.openmap.util.Debug.error("Unknown action command \""
                                + ac
                                + "\" in GraticuleLayer.actionPerformed().");
                    }
                }
            };

            kmRadioButton.addActionListener(al);
            kmRadioButton.setActionCommand(UnitOfMeasureProperty);
            meterRadioButton.addActionListener(al);
            meterRadioButton.setActionCommand(UnitOfMeasureProperty);
            nmRadioButton.addActionListener(al);
            nmRadioButton.setActionCommand(UnitOfMeasureProperty);
            mileRadioButton.addActionListener(al);
            mileRadioButton.setActionCommand(UnitOfMeasureProperty);

        }
        if (unitOfMeasure.equalsIgnoreCase("km")) {
            kmRadioButton.setSelected(true);
        } else if (unitOfMeasure.equalsIgnoreCase("m")) {
            meterRadioButton.setSelected(true);
        } else if (unitOfMeasure.equalsIgnoreCase("nm")) {
            nmRadioButton.setSelected(true);
        } else if (unitOfMeasure.equalsIgnoreCase("mile")) {
            mileRadioButton.setSelected(true);
        }
        return palette;
    }

}