无法将现有的SQLite数据库导入Android应用程序

Question

I have developed an iPhone app and right now I am working in cloning it for Android. I have used a SQLite database in my iPhone app which has about 1000s of pre-filled rows. Now I want to import this database to Android app. I have already added the database in databases folder in assets. I have checked some tutorials on the net and have done following coding for this:

MainActivity:

public class MainActivity extends ListActivity {
    private Cursor employees;
    private MyDatabase db;
    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);

        DataBaseHelper myDbHelper;
        myDbHelper = new DataBaseHelper(this);

        try {

            myDbHelper.createDataBase();

    } catch (SQLException ioe) {

        //throw new Error("Unable to create database");

    }

    try {

        myDbHelper.openDataBase();

    }catch(SQLException sqle){

        throw sqle;

    }
    }

    @Override
    protected void onDestroy() {
        super.onDestroy();
        employees.close();
        db.close();
    }
}

DatabaseHelper

public class DataBaseHelper extends SQLiteOpenHelper{
    //http://www.reigndesign.com/blog/using-your-own-sqlite-database-in-android-applications/
    //The Androids default system path of your application database.

    private static String DB_PATH = "/data/data/com.example.database/databases";

    private static String DB_NAME = "fit.sqlite";

    private SQLiteDatabase myDataBase; 

    private final Context myContext;

    /**
     * Constructor
     * Takes and keeps a reference of the passed context in order to access to the application assets and resources.
     * @param context
     */
    public DataBaseHelper(Context context) {

        super(context, DB_NAME, null, 1);
        this.myContext = context;
    }

    /**
     * Creates a empty database on the system and rewrites it with your own database.
     * */
    public void createDataBase() {

        boolean dbExist;
        try {

             dbExist = checkDataBase();


        } catch (SQLiteException e) {

            e.printStackTrace();
            throw new Error("database dose not exist");

        }

        if(dbExist){
        //do nothing - database already exist
        }else{

            try {

                copyDataBase();


            } catch (IOException e) {

                e.printStackTrace();
                throw new Error("Error copying database");

            }
    //By calling this method and empty database will be created into the default system path
    //of your application so we are gonna be able to overwrite that database with our database.
        this.getReadableDatabase();


    }

    }

    /**
     * Check if the database already exist to avoid re-copying the file each time you open the application.
     * @return true if it exists, false if it doesn't
     */
    private boolean checkDataBase(){

        SQLiteDatabase checkDB = null;

        try{
            String myPath = DB_PATH +"/"+ DB_NAME;

            checkDB = SQLiteDatabase.openDatabase(myPath, null, SQLiteDatabase.OPEN_READONLY);
        }catch(SQLiteException e){

        //database does't exist yet.
            //throw new Error("database doest exist yet.");

        }

        if(checkDB != null){

        checkDB.close();

        }

        return checkDB != null ? true : false;
    }

    /**
     * Copies your database from your local assets-folder to the just created empty database in the
     * system folder, from where it can be accessed and handled.
     * This is done by transfering bytestream.
     * */
    private void copyDataBase() throws IOException{

        //Open your local db as the input stream
        InputStream myInput = myContext.getAssets().open(DB_NAME);

        // Path to the just created empty db
        String outFileName = DB_PATH +"/"+ DB_NAME;
        File databaseFile = new File( DB_PATH);
         // check if databases folder exists, if not create one and its subfolders
        if (!databaseFile.exists()){
            databaseFile.mkdir();
        }

        //Open the empty db as the output stream
        OutputStream myOutput = new FileOutputStream(outFileName);

        //transfer bytes from the inputfile to the outputfile
        byte[] buffer = new byte[1024];
        int length;
        while ((length = myInput.read(buffer))>0){
        myOutput.write(buffer, 0, length);
        }

        //Close the streams
        myOutput.flush();
        myOutput.close();
        myInput.close();

    }

    public void openDataBase() throws SQLException{

        //Open the database
        String myPath = DB_PATH + DB_NAME;
        myDataBase = SQLiteDatabase.openDatabase(myPath, null, SQLiteDatabase.OPEN_READONLY);

    }

    @Override
    public synchronized void close() {

            if(myDataBase != null)
                myDataBase.close();

            super.close();

    }

    @Override
    public void onCreate(SQLiteDatabase db) {

    }

    @Override
    public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {

    }
}

But I am getting following error:

05-29 08:34:25.257: E/SQLiteLog(27579): (14) cannot open file at line 30176 of [00bb9c9ce4]
05-29 08:34:25.317: E/SQLiteLog(27579): (14) os_unix.c:30176: (2) open(/data/data/com.example.database/databases/fit.sqlite) - 
05-29 08:34:25.426: E/SQLiteDatabase(27579): Failed to open database '/data/data/com.example.database/databases/fit.sqlite'.
05-29 08:34:25.426: E/SQLiteDatabase(27579): android.database.sqlite.SQLiteCantOpenDatabaseException: unknown error (code 14): Could not open database
05-29 08:34:25.437: W/System.err(27579): java.io.FileNotFoundException: fit.sqlite
05-29 08:34:25.496: W/System.err(27579):    

Answer 1

确保已将此行添加到AndroidManifest.xml文件中：并且永远不会通过try和catch处理错误，并且避免将任何内容放入catch的主体中，至少放入此内容如果您不知道如何防止崩溃e.printStackTrace();