8Motions blog

Good news, OpenCellID is taking off in a great way. Nick Gering from Device54 contributed by providing some informations about some cells located in London and Barcelona! So thanks Nick for the contribution

Ok, following some requests, here is another tutorial on how to use the J2memap library. First, note that if you just want to display a KML file on mobile, you can use 8Motions directly, no need to create your own application.

Anyway, here we are going to show you how to create a very simple app that display a KML file on a cell phone. First, download the J2memap library (you need to be registered to download it), and put thelibraryCLDC11.jar (or 10.jar) as a library of your project. In netbeans, you do Properties,add jar/zip,select the jar file.

Here I take a KML file, but it could be also a GPX file, LOC or GEORSS file….

Then, here is the code:

package com.eightmotions.LoadTrack;
import javax.microedition.midlet.*;
import javax.microedition.lcdui.*;
import com.eightmotions.util.*;
import com.eightmotions.map.*;
/**
 *
 * @author tlandspurg
 * @version
 */
public class LoadTrack extends MIDlet implements TrackNotifier {

    MapCanvas m_map;
    Display m_display;
    public void startApp() {
        UtilMidp.checkMIDP(this); //Initialise the utility library…

        // Initialize the map, get the display, and put the map on it
        m_map=new MapCanvas();
        m_display=Display.getDisplay(this);
        m_display.setCurrent(m_map);     

        // Load a track, and display this track to a map
        Track track=Track.getTrack(m_display,“http://www.8motions.com/map/showKml/107″,“Loading Track”,m_map);
        // Listen for track loaded event…
        track.setNotifier(this);
    }

    public void pauseApp() { }

    public void destroyApp(boolean unconditional) {   }

    /* When the track has been loaded, display it… */
    public void onTrackLoaded(Track tr) {
        m_map.displayTrack(tr,true);
    }

    public void onTrackCreated(Track t) { };

    public void onTrackSaved(Track t) {};
}

Here is the result:

Jon Spinney from Maperture blog pointed on my previous post the effort of Christopher Schmidt from GSMLoc to create the same kind of database. So thanks to both of them, I’ve integrated the previous database of GPS cell, and we are now at 15301 cells covered with 541728 mesurements…

Here is a project that I wanted to introduce to you: OpenCellID.The purpose of this project is to create an OpenSource database of GSM cells.

Why? Because this can be used as a “cheap” way to get your location. There is not a lot of phones that provides this access to JavaMe application (mostly SonyEricsson), but this may change in the near future.
The idea is do it in a transparent way for end user, thanks to 8Motions or other applications. This is not a new idea, as Google probably made the same for his GoogleMap mobile application. The only issue, is that the application needs to access to two informations:

• the cellID
• the GPS position

and for now, no handset provides this. N95 for instance, haves a GPS but does not provide CellID information in JavaME. Latest SonyEricsson phone, provides CellID, but not GPS position. I think that new GPS enabled handsets will provide both, but for new you need to use a SonyEricsson phone and an external bluetooth receiver….

You can check the result of collected data on the OpenCellID.org web site….

There were other initiatives like this, but the idea is to provide the Datas as an OpenSource information. The code of the project is hosted on Google Code.

Identificateurs Technorati : cellid, mobile, opencellid, gsm, towers