如何使用我自己的sqlite数据库？

有人告诉我,如果我试图在SQLiteOpenHelper的onCreate()中复制文件,那就太晚了.因此复制文件代码无法复制完整的文件.

所以我需要先使用adb或ddms拉数据库吗？

那么,任何人都可以教我如何使用我自己的数据库？
你能告诉我这个设置吗？

>创建一个实用程序类,通过将静态数据库从资产复制到正确的目录中来创建静态数据库,但不会因为SQLiteOpenHelper格式而陷入困境.
>使用相同的实用程序类通过使用SQLiteDatabase.openDatabase()打开数据库

编辑：这是我创建的这个实用程序类的一个版本;它不是很完整,但你会得到漂移.

public class DbUtils {
    private static final String DB_PATH = "/data/data/com.mypackage.myapp/databases/";
    private static final String DB_NAME = "my.db";

    public static void createDatabaseIfNotExists(Context context) throws IOException {
        boolean createDb = false;

        File dbDir = new File(DB_PATH);
        File dbFile = new File(DB_PATH + DB_NAME);
        if (!dbDir.exists()) {
            dbDir.mkdir();
            createDb = true;
        }
        else if (!dbFile.exists()) {
            createDb = true;
        }
        else {
            // Check that we have the latest version of the db
            boolean doUpgrade = false;

            // Insert your own logic here on whether to upgrade the db; I personally
            // just store the db version # in a text file,but you can do whatever
            // you want.  I've tried MD5 hashing the db before,but that takes a while.

            // If we are doing an upgrade,basically we just delete the db then
            // flip the switch to create a new one
            if (doUpgrade) {
                dbFile.delete();
                createDb = true;
            }
        }

        if (createDb) {
            // Open your local db as the input stream
            InputStream myInput = context.getAssets().open(DB_NAME);

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

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

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

    public static SQLiteDatabase getStaticDb() {
        return SQLiteDatabase.openDatabase(DB_PATH + DB_NAME,null,SQLiteDatabase.OPEN_READONLY);
    }
}

（编辑：李大同）

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