Dies ist mein erster Beitrag! Ich hoffe du kannst mir helfen! : -)

Ich habe den Code aus dem NotePadExample des Entwicklerdokuments verwendet, um eine Datenbank zu erstellen. Jetzt möchte ich eine zweite Tabelle hinzufügen, um verschiedene Daten zu speichern. Ich kann problemlos Notizen hinzufügen, und die Notizentabelle wird auf ähnliche Weise wie meine Routentabelle erstellt. Ich habe den angegebenen Code einfach "kopiert" und bearbeitet, aber wenn ich versuche, ihn in die neue Tabelle einzufügen, erhalte ich die Fehlermeldung:

"0ERROR / Database (370): android.database.sqlite.SQLiteException: keine solche Tabelle: routes:, beim Kompilieren: INSERT INTO routes (Zeile, Ankunft, Dauer, Start) VALUES (?,?,?,?); "

Kann jemand bitte einen kurzen Blick auf meine DbAdapter-Klasse werfen, insbesondere auf die onCreate () -Methode. und gib mir einen Tip oder eine Lösung? Ich sehe wirklich kein Problem. Mein Code wird fehlerfrei kompiliert.

CODE

public class DbAdapter {

public static final String KEY_FROM  = "title";
public static final String KEY_TO    = "body";
public static final String KEY_ROWID = "_id";

public static final String KEY_START    = "start";
public static final String KEY_ARRIVAL  = "arrival";
public static final String KEY_LINE     = "line";
public static final String KEY_DURATION = "duration";

private static final String DATABASE_NAME           = "data";
private static final String DATABASE_NOTESTABLE     = "notes";
private static final String DATABASE_ROUTESTABLE    = "routes";

private static final String TAG = "DbAdapter";
private DatabaseHelper mDbHelper;
private SQLiteDatabase mDb;

/**
 * Database creation sql statement
 */
private static final String DATABASE_CREATE_NOTES =
        "create table notes (_id integer primary key autoincrement, "
                + "title text not null, body text not null)";

private static final String DATABASE_CREATE_ROUTES =
    "create table routes (_id integer primary key autoincrement, "
            + "start , arrival , " 
            + "line , duration );";

private static final int DATABASE_VERSION = 3;

private final Context mCtx;

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_NOTES);
        Log.d(TAG, "created notes table");

        db.execSQL(DATABASE_CREATE_ROUTES);
        Log.d(TAG, "created routes table");
    }

    @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 notes");
        db.execSQL("DROP TABLE IF EXISTS routes");
        onCreate(db);
    }
}

/**
 * Constructor - takes the context to allow the database to be
 * opened/created
 * 
 * @param ctx the Context within which to work
 */
public DbAdapter(Context ctx) {
    this.mCtx = ctx;
}

/**
 * Open the notes database. If it cannot be opened, try to create a new
 * instance of the database. If it cannot be created, throw an exception to
 * signal the failure
 * 
 * @return this (self reference, allowing this to be chained in an
 *         initialization call)
 * @throws SQLException if the database could be neither opened or created
 */
public DbAdapter open() throws SQLException {
    mDbHelper = new DatabaseHelper(mCtx);
    mDb = mDbHelper.getWritableDatabase();
    return this;
}

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


/**
 * Create a new note using the title and body provided. If the note is
 * successfully created return the new rowId for that note, otherwise return
 * a -1 to indicate failure.
 * 
 * @param title the title of the note
 * @param body the body of the note
 * @return rowId or -1 if failed
 */
public long createNote(String title, String body) {

    ContentValues initialValues = new ContentValues();
    initialValues.put(KEY_FROM, title);
    initialValues.put(KEY_TO, body);

    return mDb.insert(DATABASE_NOTESTABLE, null, initialValues);
}

/**
 * Create a new route using the title and body provided. If the route is
 * successfully created return the new rowId for that route, otherwise return
 * a -1 to indicate failure.
 * 
 * @param start the start time of the route
 * @param arrival the arrival time of the route
 * @param line the line number of the route
 * @param duration the routes duration 
 * @return rowId or -1 if failed
 */

public long createRoute(String start, String arrival, String line, String duration){

    ContentValues initialValues = new ContentValues();
    initialValues.put(KEY_START, start);
    initialValues.put(KEY_ARRIVAL, arrival);
    initialValues.put(KEY_LINE, line);
    initialValues.put(KEY_DURATION, duration);

    return mDb.insert(DATABASE_ROUTESTABLE, null, initialValues);
}

/**
 * Delete the note with the given rowId
 * 
 * @param rowId id of note to delete
 * @return true if deleted, false otherwise
 */
public boolean deleteNote(long rowId) {
    return mDb.delete(DATABASE_NOTESTABLE, KEY_ROWID + "=" + rowId, null) > 0;
}

/**
 * Return a Cursor over the list of all notes in the database
 * 
 * @return Cursor over all notes
 */
public Cursor fetchAllNotes() {
    return mDb.query(DATABASE_NOTESTABLE, new String[] {KEY_ROWID, KEY_FROM,
            KEY_TO}, null, null, null, null, null);
}

/**
 * Return a Cursor over the list of all routes in the database
 * 
 * @return Cursor over all routes
 */
public Cursor fetchAllRoutes() {
    return mDb.query(DATABASE_ROUTESTABLE, new String[] {KEY_ROWID, KEY_START,
            KEY_ARRIVAL, KEY_LINE, KEY_DURATION}, null, null, null, null, null);
}

/**
 * Return a Cursor positioned at the note that matches the given rowId
 * 
 * @param rowId id of note to retrieve
 * @r,eturn Cursor positioned to matching note, if found
 * @throws SQLException if note could not be found/retrieved
 */
public Cursor fetchNote(long rowId) throws SQLException {
    Cursor mCursor =
            mDb.query(true, DATABASE_NOTESTABLE, new String[] {KEY_ROWID,
                    KEY_FROM, KEY_TO}, KEY_ROWID + "=" + rowId, null,
                    null, null, null, null);
    if (mCursor != null) {
        mCursor.moveToFirst();
    }
    return mCursor;

}

/**
 * Return a Cursor positioned at the route that matches the given rowId
 * 
 * @param rowId id of route to retrieve
 * @return Cursor positioned to matching route
 * @throws SQLException if note could not be found/retrieved
 */
public Cursor fetchRoute(long rowId) throws SQLException {
    Cursor mCursor =
            mDb.query(true, DATABASE_ROUTESTABLE, new String[] {KEY_ROWID,
                    KEY_START, KEY_ARRIVAL, KEY_LINE, KEY_DURATION}, KEY_ROWID + "=" + rowId, null,
                    null, null, null, null);
    if (mCursor != null) {
        mCursor.moveToFirst();
    }
    return mCursor;

}

/**
 * Update the note using the details provided. The note to be updated is
 * specified using the rowId, and it is altered to use the title and body
 * values passed in
 * 
 * @param rowId id of note to update
 * @param title value to set note title to
 * @param body value to set note body to
 * @return true if the note was successfully updated, false otherwise
 */
public boolean updateNote(long rowId, String title, String body) {
    ContentValues args = new ContentValues();
    args.put(KEY_FROM, title);
    args.put(KEY_TO, body);
    return mDb.update(DATABASE_NOTESTABLE, args, KEY_ROWID + "=" + rowId, null) > 0;
}

public void deleteRoutesTable(SQLiteDatabase db){
    db.delete("routes", null, null);
}
}

HINZUFÜGE

Ich möchte eine Methode wie @ implementier

public void deleteTableRoutes(SQLiteDataBase db){
 db.delete("routes", null, null);
}

Mein Problem: Ich möchte diese Funktion von einem Punkt aus aufrufen, an dem ich keinen Verweis auf meine Datenbank habe (soweit ich weiß), um sie als Argument für meine deleteTableRoutes (SQLiteDataBase) zu übergeben ...