Question

i am trying to create a Map Activity and i have been able to successfully have a static string of coordinates to be read from the main activity, however this is hard coded and i wish you insert these coordinates into an SQLite Database and for them to be read.
I have tried looking around but i simply cant get the answer that i am looking for, and i would grateful if someone could help me out please

Heres my Main Activity – GMapsActivity.java:

    /** Called when the activity is first created. */
@Override
public void onCreate(Bundle savedInstanceState) 
{   
    super.onCreate(savedInstanceState);
    setContentView(R.layout.main);

    mapView = (MapView)findViewById(R.id.map_view);
    mapView.setBuiltInZoomControls(true);
    //mapView.setStreetView(true);
    mapController = mapView.getController();

    String coordinates[] = {"51.52241608253253","-0.1318359375"};
    double lat = Double.parseDouble(coordinates[0]);
    double lng = Double.parseDouble(coordinates[1]);
    GeoPoint general = new GeoPoint((int) (lat * 1E6), (int) (lng * 1E6) );
    mapController.setZoom(10);
    mapController.animateTo(general);

    mapOverlays = mapView.getOverlays();
    drawable = this.getResources().getDrawable(R.drawable.blue);
    itemizedOverlay = new NewItemizedOverlay(drawable, this);

    GeoPoint point = new GeoPoint((int)(51.555890943494276*1E6), (int)(-0.39989858865737915*1E6));
    OverlayItem overlayitem = new OverlayItem(point, "Greenword Veterinary" , "57 Station Approach, South Ruislip, Ruislip, Middlesex, HA4 6SL, 020 8845 8144");
    itemizedOverlay.addOverlay(overlayitem);

    GeoPoint point2 = new GeoPoint((int)(51.598707*1E6), (int)(-0.393416*1E6));
    OverlayItem overlayitem2 = new OverlayItem(point2, "MediVet Pinner" , "2A Pinner Green, Pinner, Middlesex, HA5 2AA, 020 8866 0727");
    itemizedOverlay.addOverlay(overlayitem2);

    GeoPoint point3 = new GeoPoint((int)(51.670865*1E6), (int)(-0.397034*1E6));
    OverlayItem overlayitem3 = new OverlayItem(point3, "MediVet Watford" , "237 Saint Albans Road, Watford, Hertfordshire WD24 5BP, 01923 243 429");
    itemizedOverlay.addOverlay(overlayitem3);
    mapOverlays.add(itemizedOverlay);

    myLocationOverlay = new MyLocationOverlay(this, mapView);
    mapView.getOverlays().add(myLocationOverlay);

And this is my database creator – DatabaseManager.java

package com.javacodegeeks.android.googlemaps;
import android.content.Context;
import android.database.sqlite.SQLiteDatabase;
import android.database.sqlite.SQLiteDatabase.CursorFactory;
import android.database.sqlite.SQLiteOpenHelper;

public class DatabaseManager {

public static final String KEY_ID = "_id";
public static final String KEY_LAT = "vetlat";
public static final String KEY_LONGI = "vetlongi";
public static final String KEY_NAME = "vetname";
public static final String KEY_INFO = "vetinfo";

private static final String DATABASE_NAME = "myvet.db";
private static final String DATABASE_TABLE = "vetLocations";
private static final int DATABASE_VERSION = 1;

private DbHelper ourHelper;
private final Context ourContext;
private SQLiteDatabase ourDB;

private static class DbHelper extends SQLiteOpenHelper
{

    public DbHelper(Context context) 
    {
        super(context, DATABASE_NAME, null, DATABASE_VERSION);
        // TODO Auto-generated constructor stub
    }

    @Override
    public void onCreate(SQLiteDatabase db) 
    {
        // TODO Auto-generated method stub
        db.execSQL("CREATE TABLE " + DATABASE_TABLE + " (" + 
                KEY_ID + " INTEGER PRIMARY KEY AUTOINCREMENT, " + 
                KEY_LAT + "REAL NOT NULL," + 
                KEY_LONGI + "REAL NOT NULL," +
                KEY_NAME + "TEXT NOT NULL," +
                KEY_INFO + "TEXT NOT NULL);"
        );
    }

    @Override
    public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {
        // TODO Auto-generated method stub
        db.execSQL("DROP TABLE IF EXISTS " + DATABASE_TABLE);
        onCreate(db);
    }

}

public DatabaseManager(Context c)
{
    ourContext = c;
}

public DatabaseManager open()
{
    ourHelper = new DbHelper(ourContext);
    ourDB = ourHelper.getReadableDatabase();
    return this;
}

public void close()
{
    ourHelper.close();
}

}

I am new to Android Programming so i would be grateful is someone could actually show me snippets of code as opposed to general directions since i dont really understand them lol

EDIT:
I have created database entries in an SQLite browser
How would i be able to make the main activity file read the values from that file?

A general idea that the code would try and call the values such as:
SELECT * FROM the DB
Put into Array
then loop it

points = ((int)([lat_value_from_db1*E6]), ((int)([longi_value_from_db1*E6]);
overlay = (points, [name_value_from_db], [info_value_from_db]);
itemizedOverylay.addOverlay(allOverlays);

Its just im really not sure how to implement this :/

I would really appreciate any form of help

Thank You in advance

Answer 1

First, create a class as an object of database record DatabaseObject.java:

public class DatabaseObject {

       int _id;
       double _lat;
       double _lng;
       String _name;
       String _info;

        // Empty constructor
        public DatabaseObject(){

        }
        // constructor
        public DatabaseObject(int id, double lat, double lng,String name ,String info){
            this._id = id;
            this._lat=lat;
            this._lng=lng;
            this._name=name;
            this._info=info;
        }
        public DatabaseObject(double lat, double lng,String name ,String info){
             this._lat=lat;
                this._lng=lng;
                this._name=name;
                this._info=info;
        }
        // constructor

        // getting ID
        public int getID(){
            return this._id;
        }

        // setting id
        public void setID(int id){
            this._id = id;
        }


        public double getlat(){
            return this._lat;
        }

        public void setlat(double lat){
            this._lat = lat;
        }

        public double getlng(){
            return this._lng;
        }

        public void setlng(double lng){
            this._lng = lng;
        }

        public String getname(){
            return this._name;
        }

        // setting id
        public void setname(String name){
            this._name = name;
        }

        public String getinfo(){
            return this._info;
        }

        // setting id
        public void setinfo(String info){
            this._infor= info;
        }   
}

Then add these two functions in your DatabaseManager.java:

// Getting one database object by id
public DatabaseObject get_DatabaseObject(int id) {
       SQLiteDatabase db = this.getReadableDatabase();

        Cursor cursor = db.query(TABLE_NAME, new String[] { KEY_ID,
                KEY_LAT, KEY_LONGI,KEY_NAME,KEY_INFO }, KEY_ID + "=?",
                new String[] { String.valueOf(id) }, null, null,null,null);
        if (cursor != null)
            cursor.moveToFirst();

        DatabaseObject data = new DatabaseObject(Integer.parseInt(cursor.getString(0)),
                Double.parseDouble(cursor.getString(1)), Double.parseDouble(cursor.getString(2)),cursor.getString(3), cursor.getString(4));
        // return database object
       return data;
   }

    // Getting All database objects
    public List<DatabaseObject> getAllDatabaseObject() {
        List<DatabaseObject> contactList = new ArrayList<DatabaseObject>();
       //  Select All Query
        String selectQuery = "SELECT  * FROM " + TABLE_NAME;

        SQLiteDatabase db = this.getWritableDatabase();
        Cursor cursor = db.rawQuery(selectQuery, null);

        // looping through all rows and adding to list
        if (cursor.moveToFirst()) {
           do {
               DatabaseObject data = new DatabaseObject();
               data.setID(Integer.parseInt(cursor.getString(0)));
                data.setLAT( Double.parseDouble(cursor.getString(1)));
                data.setLONGI( Double.parseDouble(cursor.getString(2)));
                data.setNAME(cursor.getString(3));
               data.setINFO(cursor.getString(4));

              //   Adding contact to list
               contactList.add(data);
            } while (cursor.moveToNext());
        }

        // return database object list
       return dataList;
    }

And now use these in any activity like this:

1- Declare this as global variable:

DatabaseManager db = new DatabaseManager(this);

2- Retrieve all objects:

List<DatabaseObject> K = db.getAllDatabaseObject(); 

3- Use it in loop this way:

for (DatabaseObject cn : K) {
        point = new GeoPoint((int)(cn.getlat()*E6), (int)(cn.getlng()*E6));
        overlayitem = new OverlayItem(point, cn.getname(), cn.getinfo());
        itemizedOverlay.addOverlay(overlayitem);
        mapOverlays.add(itemizedOverlay);
}