codice:
package org.test_db;
import android.content.ContentValues;
import android.content.Context;
import android.database.Cursor;
import android.database.SQLException;
import android.database.sqlite.SQLiteDatabase;
import android.database.sqlite.SQLiteOpenHelper;
import android.util.Log;
public class DBadapter
{
public static final String KEY_ROWID = "_id";
public static final String KEY_LP = "languageprogram";
public static final String KEY_BODY = "body";
public static final String KEY_AUTHOR = "author";
private static final String TAG = "DBAdapter";
private static final String DATABASE_NAME = "helloworld_db";
private static final String DATABASE_TABLE = "record_type";
private static final int DATABASE_VERSION = 1;
private static final String DATABASE_CREATE =
"create table record_type (_id integer primary key autoincrement, "
+ "languageprogram text not null, body text not null, "
+ "author text not null);";
private final Context context;
private DatabaseHelper DBHelper;
private SQLiteDatabase db;
public DBadapter(Context ctx)
{
this.context = ctx;
DBHelper = new DatabaseHelper(context);
}
private static class DatabaseHelper extends SQLiteOpenHelper
{
DatabaseHelper(Context context)
{
super(context, DATABASE_NAME, null, DATABASE_VERSION);
}
@Override
public void onCreate(SQLiteDatabase db)
{
db.execSQL(DATABASE_CREATE);
}
@Override
public void onUpgrade(SQLiteDatabase db, int oldVersion,
int newVersion)
{
Log.w(TAG, "Upgrading database from version " + oldVersion
+ " to "
+ newVersion + ", which will destroy all old data");
db.execSQL("DROP TABLE IF EXISTS bodys");
onCreate(db);
}
}
//---opens the database---
public DBadapter open() throws SQLException
{
db = DBHelper.getWritableDatabase();
return this;
}
//---closes the database---
public void close()
{
DBHelper.close();
}
//---insert a body into the database---
public long insertTitle(String languageprogram, String body, String author)
{
ContentValues initialValues = new ContentValues();
initialValues.put(KEY_LP, languageprogram);
initialValues.put(KEY_BODY, body);
initialValues.put(KEY_AUTHOR, author);
return db.insert(DATABASE_TABLE, null, initialValues);
}
//---deletes a particular body---
public boolean deleteTitle(long rowId)
{
return db.delete(DATABASE_TABLE, KEY_ROWID +
"=" + rowId, null) > 0;
}
//---retrieves all the bodys---
public Cursor getAllTitles()
{
return db.query(DATABASE_TABLE, new String[] {
KEY_ROWID,
KEY_LP,
KEY_BODY,
KEY_AUTHOR},
null,
null,
null,
null,
null);
}
//---retrieves a particular body---
public Cursor getTitle(long rowId) throws SQLException
{
Cursor mCursor =
db.query(true, DATABASE_TABLE, new String[] {
KEY_ROWID,
KEY_LP,
KEY_BODY,
KEY_AUTHOR
},
KEY_ROWID + "=" + rowId,
null,
null,
null,
null,
null);
if (mCursor != null) {
mCursor.moveToFirst();
}
return mCursor;
}
//---retrieves a particular body---
public Cursor getTitlefromlc(String lp) throws SQLException
{
Cursor mCursor =
db.query(true, DATABASE_TABLE, new String[] {
KEY_ROWID,
KEY_LP,
KEY_BODY,
KEY_AUTHOR
},
"WHERE " + KEY_LP + " = " + "'" + lp + "'",
null,
null,
null,
null,
null);
if (mCursor != null) {
mCursor.moveToFirst();
}
return mCursor;
}
//---updates a body---
public boolean updateTitle(long rowId, String languageprogram,
String body, String author)
{
ContentValues args = new ContentValues();
args.put(KEY_LP, languageprogram);
args.put(KEY_BODY, body);
args.put(KEY_AUTHOR, author);
return db.update(DATABASE_TABLE, args,
KEY_ROWID + "=" + rowId, null) > 0;
}
}
è una classe di esempio che ho trovato in rete e sto modificando per studiarmi android;comunque ho provato a lanciare una query direttamente al db e funziona,la query è questa: