coordmousemode.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.

// **********************************************************************
// 
// <copyright>
// 
//  BBN Technologies
//  10 Moulton Street
//  Cambridge, MA 02138
//  [phone]
// 
//  Copyright (C) BBNT Solutions LLC. All rights reserved.
// 
// </copyright>
// **********************************************************************
// 
// $Source: /cvs/distapps/openmap/src/openmap/com/bbn/openmap/event/CoordMouseMode.java,v $
// $RCSfile: CoordMouseMode.java,v $
// $Revision: 1.5.2.2 $
// $Date: 2004/10/14 18:26:44 $
// $Author: dietrick $
// 
// **********************************************************************

package com.bbn.openmap.event;

import java.awt.event.MouseEvent;

import com.bbn.openmap.InformationDelegator;
import com.bbn.openmap.LatLonPoint;
import com.bbn.openmap.MapBean;
import com.bbn.openmap.util.Debug;

/**
 * The CoordMouseMode is an abstract MouseMode extension to
 * AbstractMouseMode that can be used for Modes that want to use the
 * BeanContext to hook up with the InformationDelegator, and to send
 * coordinate updates to be displayed in the infoline.
 */
public abstract class CoordMouseMode extends AbstractMouseMode {

    /**
     * The info delegator that will display the distance information
     */
    public InformationDelegator infoDelegator = null;

    public CoordMouseMode() {}

    /**
     * @param modeID the id for the mouse mode.
     * @param shouldConsumeEvents the mode setting, where the
     *        mousemode should pass the events on to other listeners
     *        or not, depending if one of the listeners used it or
     *        not.
     */
    public CoordMouseMode(String modeID, boolean shouldConsumeEvents) {
        super(modeID, shouldConsumeEvents);
    }

    /**
     * Set the information delegator.
     * 
     * @param id the information delegator that displays the distance
     *        values.
     */
    public void setInfoDelegator(InformationDelegator id) {
        infoDelegator = id;
    }

    /**
     * Return the information delegator.
     */
    public InformationDelegator getInfoDelegator() {
        return infoDelegator;
    }

    /**
     * Fires a mouse location to the InformationDelegator, and then
     * calls the super class method which calls the MouseSupport
     * method.
     * 
     * @param e MouseEvent to be handled
     */
    public void mouseMoved(MouseEvent e) {
        fireMouseLocation(e);
        super.mouseMoved(e);
    }

    /**
     * Fires a mouse location to the InformationDelegator, and then
     * calls the super class method which calls the MouseSupport
     * method.
     * 
     * @param e mouse event.
     */
    public void mouseDragged(MouseEvent e) {
        fireMouseLocation(e);
        super.mouseDragged(e);
    }

    /**
     * If the MouseMode has been made inactive, clean out any input
     * that might have been made to the info line.
     */
    public void setActive(boolean active) {
        if (Debug.debugging("mousemode")) {
            Debug.output("CoordMouseMode(" + getPrettyName()
                    + "): made active (" + active + ")");
        }
        if (!active && infoDelegator != null) {
            infoDelegator.requestInfoLine(new InfoDisplayEvent(this, "", InformationDelegator.COORDINATE_INFO_LINE));
        }
    }

    /**
     * Sends the mouse event location, x/y and lat/lon, to the
     * InformationDelegator.
     */
    public void fireMouseLocation(MouseEvent e) {
        int x = e.getX();
        int y = e.getY();
        LatLonPoint llp = null;
        Debug.message("mousemodedetail",
                "CoordMouseMode: firing mouse location");

        if (infoDelegator != null) {
            if (e.getSource() instanceof MapBean) {
                llp = ((MapBean) e.getSource()).getProjection().inverse(x, y);
            }
            String infoLine;
            infoLine = createCoordinateInformationLine(x, y, llp);

            // setup the info event
            InfoDisplayEvent info = new InfoDisplayEvent(this, infoLine, InformationDelegator.COORDINATE_INFO_LINE);
            // ask the infoDelegator to display the info
            infoDelegator.requestInfoLine(info);
        }
    }

    /**
     * Method to create the information string reflecting information
     * at the LatLonPoint provided. By default, will return a string
     * for the x and y, and the lat/lon. If llp is null, just the x, y
     * will be returned. This method can be changed, or overridden to
     * change what kind of coordinates (UTM, DMS, MGRS) are reflected
     * here.
     */
    protected String createCoordinateInformationLine(int x, int y,
                                                     LatLonPoint llp) {
        if (llp != null) {
            return "Lat, Lon (" + df.format(llp.getLatitude()) + ", "
                    + df.format(llp.getLongitude()) + ") - x, y (" + x + ","
                    + y + ")";
        } else {
            return "x, y (" + x + "," + y + ")";
        }
    }

    /**
     * Called when a CoordMouseMode is added to a BeanContext, or when
     * another object is added to the BeanContext after that. The
     * CoordMouseMode looks for an InformationDelegator to use to fire
     * the coordinate updates. If another InforationDelegator is added
     * when one is already set, the later one will replace the current
     * one.
     * 
     * @param someObj an object being added to the BeanContext.
     */
    public void findAndInit(Object someObj) {
        if (someObj instanceof InformationDelegator) {
            Debug.message("mousemode",
                    "NavMouseMode: found InformationDelegator");
            setInfoDelegator((InformationDelegator) someObj);
        }
    }

    /**
     * BeanContextMembershipListener method. Called when objects have
     * been removed from the parent BeanContext. If an
     * InformationDelegator is removed from the BeanContext, and it's
     * the same one that is currently held, it will be removed.
     * 
     * @param someObj an object being removed from the BeanContext.
     */
    public void findAndUndo(Object someObj) {
        if (someObj instanceof InformationDelegator) {
            if (getInfoDelegator() == (InformationDelegator) someObj) {
                setInfoDelegator(null);
            }
        }
    }
}