SQLite database tutorial doesn't work ... no idea why? [on hold]

So I'm following a tutorial about a very basic SQLite database on Android. The code shows NO ERRORS and I can open the application when I execute it. But it's supposed to show the list in my database but it doesn't ... and I don't understand why.

main.xml:

<?xml version="1.0" encoding="UTF-8"?>
<LinearLayout android:layout_height="fill_parent" 
    android:layout_width="fill_parent" 
    android:orientation="vertical" 
    xmlns:android="http://ift.tt/nIICcg"> 

    <TextView android:layout_height="wrap_content" 
        android:layout_width="fill_parent" 
        android:text="@string/hello_world"/> 
    <TextView android:layout_height="wrap_content" 
            android:layout_width="fill_parent" 
            android:id="@+id/contentlist"/> 

            </LinearLayout>

Main_Activity:

import android.app.Activity;
import android.os.Bundle;
import android.widget.TextView;

public class AndroidSQLite extends Activity {

    private SQLiteAdapter mySQLiteAdapter;


    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        TextView listContent = (TextView)findViewById(R.id.contentlist);


        mySQLiteAdapter = new SQLiteAdapter(this);
        mySQLiteAdapter.openToWrite();
        mySQLiteAdapter.deleteAll();
        mySQLiteAdapter.insert("ABCDE");
        mySQLiteAdapter.insert("FGHIJK");
        mySQLiteAdapter.insert("1234567");
        mySQLiteAdapter.insert("890");
        mySQLiteAdapter.insert("Testing");
        mySQLiteAdapter.close();


        mySQLiteAdapter = new SQLiteAdapter(this);
        mySQLiteAdapter.openToRead();
        String contentRead = mySQLiteAdapter.queueAll();
        mySQLiteAdapter.close();

        listContent.setText(contentRead);

    }
}

Adapter.java:

import android.content.ContentValues;
import android.content.Context;
import android.database.Cursor;
import android.database.sqlite.SQLiteDatabase;
import android.database.sqlite.SQLiteOpenHelper;
import android.database.sqlite.SQLiteDatabase.CursorFactory;

public class SQLiteAdapter {

    public static final String MYDATABASE_NAME = "MY_DATABASE";
    public static final String MYDATABASE_TABLE = "MY_TABLE";
    public static final int MYDATABASE_VERSION = 1;
    public static final String KEY_CONTENT = "Content";


    private static final String SCRIPT_CREATE_DATABASE =
        "create table " + MYDATABASE_TABLE + " ("
        + KEY_CONTENT + " text not null);";

    private SQLiteHelper sqLiteHelper;
    private SQLiteDatabase sqLiteDatabase;

    private Context context;

    public SQLiteAdapter(Context c){
        context = c;
    }

    public SQLiteAdapter openToRead() throws android.database.SQLException {
        sqLiteHelper = new SQLiteHelper(context, MYDATABASE_NAME, null, MYDATABASE_VERSION);
        sqLiteDatabase = sqLiteHelper.getReadableDatabase();
        return this;    
    }

    public SQLiteAdapter openToWrite() throws android.database.SQLException {
        sqLiteHelper = new SQLiteHelper(context, MYDATABASE_NAME, null, MYDATABASE_VERSION);
        sqLiteDatabase = sqLiteHelper.getWritableDatabase();
        return this;    
    }

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

    public long insert(String content){

        ContentValues contentValues = new ContentValues();
        contentValues.put(KEY_CONTENT, content);
        return sqLiteDatabase.insert(MYDATABASE_TABLE, null, contentValues);
    }

    public int deleteAll(){
        return sqLiteDatabase.delete(MYDATABASE_TABLE, null, null);
    }

    public String queueAll(){
        String[] columns = new String[]{KEY_CONTENT};
        Cursor cursor = sqLiteDatabase.query(MYDATABASE_TABLE, columns, 
                null, null, null, null, null);
        String result = "";

        int index_CONTENT = cursor.getColumnIndex(KEY_CONTENT);
        for(cursor.moveToFirst(); !(cursor.isAfterLast()); cursor.moveToNext()){
            result = result + cursor.getString(index_CONTENT) + "\n";
        }

        return result;
    }

    public class SQLiteHelper extends SQLiteOpenHelper {

        public SQLiteHelper(Context context, String name,
                CursorFactory factory, int version) {
            super(context, name, factory, version);
        }

        @Override
        public void onCreate(SQLiteDatabase db) {
            // TODO Auto-generated method stub
            db.execSQL(SCRIPT_CREATE_DATABASE);
        }

        @Override
        public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {
            // TODO Auto-generated method stub

        }

    }

}