Question

I got this class, which creates database at the 1st run of the app. I wanted to fill one table with some example values from strings.xml. Basically I’d do this like:

private static final String CATEGORIES_FILL = "INSERT INTO categories VALUES ('', " + getString(R.string.fuel) + "); " +
                                              "INSERT INTO categories VALUES ('', " + getString(R.string.food) + "); " +
                                              "INSERT INTO categories VALUES ('', " + getString(R.string.treatment) + "); " +
                                              "INSERT INTO categories VALUES ('', " + getString(R.string.salary) + "); ";

The problem is, the class is not an activity, and string must be static so I can use

db.execSQL(CATEGORIES_FILL);

Please correct my approach so I could use strings.xml to do that.

I assume I could do that in my activity class surrounding it with try block, but I don’t like the idea of executing this every time I open the activity.

Fragment of database class

private static class DatabaseHelper extends SQLiteOpenHelper {


    DatabaseHelper(Context context) {
        super(context, DATABASE_NAME, null, DATABASE_VERSION);


        final String CATEGORIES_FILL = "INSERT INTO categories VALUES ('', " + context.getString(R.string.fuel) + "); " +
        "INSERT INTO categories VALUES ('', " + context.getString(R.string.food) + "); " +
        "INSERT INTO categories VALUES ('', " + context.getString(R.string.treatment) + "); " +
        "INSERT INTO categories VALUES ('', " + context.getString(R.string.salary) + "); "; 
    }

    /* Tworzenie tabel
     * @see android.database.sqlite.SQLiteOpenHelper#onCreate(android.database.sqlite.SQLiteDatabase)
     */
    @Override
    public void onCreate(SQLiteDatabase db) {
        db.execSQL(DATABASE_CREATE);
        db.execSQL(CATEGORIES_FILL); //need the way to access this final here
        db.execSQL(EXPENSES_CREATE);
        db.execSQL(INCOMES_CREATE);
        db.execSQL(BUGS_CREATE);            
    }

Answer 1

Something vaguely like this.

Add to res/values/<yourchoiceoffilename>.xml & add your string references to a string-array.

<resources>
    <string-array name="categories">
        <item>@string/fuel</item>
        <item>@string/food</item>
        <item>@string/treatment</item>
        <item>@string/salary</item>
    </string-array>
</resources>

Create a SQLiteStatement on your database.

SQLiteDatabase db = ...;
SQLiteStatement insert = db.compileStatement("INSERT INTO categories (yourcolumnnamehere) VALUES (?)");

//process each string
for (String category : getResources().getStringArray(R.array.categories)) 
{
    insert.bindValue(1, category);
    long id = insert.executeInsert(); // In case you care about the row id.
}

Edit: And, consider doing something like following to your class (I’ve probably left a bug or two in there, but you should get the gist of it):

private static class DatabaseHelper extends SQLiteOpenHelper {
    ...
    // Replace 'yourcolumnnamehere' with whatever your column is actually named.
    private static final String INSERT_CATEGORY = "INSERT INTO categories (yourcolumnamehere) VALUES (?)"
    ...
    ...

    private final String[] mCategories;
    DatabaseHelper(Context context) {
        super(context, DATABASE_NAME, null, DATABASE_VERSION);
        mCategories = context.getResources().getStringArray(R.array.categories);
    }

    @Override
    public void onCreate(SQLiteDatabase db) {
        db.execSQL(DATABASE_CREATE);

        // Here you create the SQLiteStatement that will be used
        // to add categories. The values are stored in mCategories.
        SQLiteStatement statement = db.compileStatement(INSERT_CATEGORY);
        for (String category : mCategories) {
            statement.bindValue(1, category);
            statement.executeInsert();
        }
        statement.close();

        db.execSQL(EXPENSES_CREATE);
        db.execSQL(INCOMES_CREATE);
        db.execSQL(BUGS_CREATE);            
    }