Download sqlite file and use it in my android app

Question

I am trying to DL a .sqlite file in my android app, store it and then use it. If I understood correctly I first need to DL the db from an url, put it in the assets folder and then copy it to the : "/data/data/{package_name}/databases/" folder. I found this answer helping me to copy the DB from the assets directory but I still can't download the DB at first. Simple export and import of a SQLite database on Android

I am fairly new in android dev, if someone know a step by step tutorial or an open source app doing that it would be really great.

Answer 1

To manually create database, use Contract Android class.Use SQLiteBrowser Download .sqlite file using Monitor in the Android Studio to get the data.

Answer 2

First: Create a folder have name: assets in app/assets
Then: Copy db.sqlite to folder assets

1. Create SqliteHelper.class

public class SqliteHelper extends SQLiteOpenHelper {

public static String DB_PATH = "/data/data/package.your.name/databases/";
private static String DB_NAME = "your_name_db.sqlite";
private final Context context;

public SqliteHelper(Context context) {
    super(context, DB_NAME, null, 1);
    this.context = context;
}

/**
 * copy database from assets to the device if not existed
**/
public boolean isCreatedDatabase() throws IOException {
    // Default là đã có DB
    boolean result = true;
    // Nếu chưa tồn tại DB thì copy từ Asses vào Data
    if (!checkExistDataBase()) {
         this.getReadableDatabase();
        try {
            copyDataBase();
            result = false;
        } catch (Exception e) {
            throw new Error("Error copying database");
        }
        // nó chưa tồn tại thì file sharedpreferences cũng chưa tồn tại tạo luôn
        //isCreateSP();
    }
    return result;
}


/**
 * check database exist on the device?
 */
private boolean checkExistDataBase() {

    try {
        String myPath = DB_PATH + DB_NAME;
        File fileDB = new File(myPath);
        if (fileDB.exists()) {
            return true;
        } else
            return false;
    } catch (Exception e) {
        return false;
    }
}

/**
 * copy database from assets folder to the device
 * 
 * @throws IOException
 */
private void copyDataBase() throws IOException {
    InputStream myInput = context.getAssets().open(DB_NAME);
    OutputStream myOutput = new FileOutputStream(DB_PATH + DB_NAME);
    byte[] buffer = new byte[1024];
    int length;
    while ((length = myInput.read(buffer)) > 0) {
        myOutput.write(buffer, 0, length);
    }
    myOutput.flush();
    myOutput.close();
    myInput.close();
}

@Override
public void onCreate(SQLiteDatabase db) {
    // TODO Auto-generated method stub

}

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

}
}

2. in MainActivity.class, create method isCreateDB : "copy data from asset to data/data/...."

public class MainActivity extends Activity {

@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_test);

    isCreateDB();
}

    /*
 * Copy db from asset vào database
 */
private boolean isCreateDB() {
    SqliteHelper data = new SqliteHelper(this);
    try {

        return data.isCreatedDatabase();

    } catch (IOException e) {
        Toast.makeText(this, "Error copying database", Toast.LENGTH_LONG).show();
        e.printStackTrace();
        return false;
    }
}