如何在android应用程序中获取我自己的SQLiteDatabase文件?
我的android应用程序需要在eclipse项目中使用现有的SQLiteDatabase文件(xxx.db),我应该将该数据库文件放在哪个项目文件夹中?如何在代码中获取数据库?只需将xxx.db文件放在资产文件夹中即可如何在android应用程序中获取我自己的SQLiteDatabase文件?,android,eclipse,sqlite,Android,Eclipse,Sqlite,我的android应用程序需要在eclipse项目中使用现有的SQLiteDatabase文件(xxx.db),我应该将该数据库文件放在哪个项目文件夹中?如何在代码中获取数据库?只需将xxx.db文件放在资产文件夹中即可 public class DatabaseHelper extends SQLiteOpenHelper { private static String TAG = "DataBaseHelper"; // Tag just for the LogCat window
public class DatabaseHelper extends SQLiteOpenHelper {
private static String TAG = "DataBaseHelper"; // Tag just for the LogCat window
// destination path (location) of our database on device
private static String DB_PATH = "";
private static String DB_NAME = "xxx.db";// Database name
private SQLiteDatabase mDataBase;
private final Context mContext;
public DatabaseHelper(Context context) {
super(context, DB_NAME, null, 1);// 1? its Database Version
if (android.os.Build.VERSION.SDK_INT >= 4.2) {
DB_PATH = context.getApplicationInfo().dataDir + "/databases/";
} else {
DB_PATH = context.getFilesDir().getPath() + context.getPackageName() + "/databases/";
}
this.mContext = context;
}
public void createDataBase() throws IOException {
// If database not exists copy it from the assets
boolean mDataBaseExist = checkDataBase();
if (!mDataBaseExist) {
this.getReadableDatabase();
this.close();
try {
// Copy the database from assests
copyDataBase();
Log.e(TAG, "createDatabase database created");
} catch (IOException mIOException) {
throw new Error("ErrorCopyingDataBase");
}
}
}
// Check that the database exists here: /data/data/your package/databases/Da
// Name
private boolean checkDataBase() {
File dbFile = new File(DB_PATH + DB_NAME);
return dbFile.exists();
}
// Copy the database from assets
private void copyDataBase() throws IOException {
InputStream mInput = mContext.getAssets().open(DB_NAME);
String outFileName = DB_PATH + DB_NAME;
OutputStream mOutput = new FileOutputStream(outFileName);
byte[] mBuffer = new byte[1024];
int mLength;
while ((mLength = mInput.read(mBuffer)) > 0) {
mOutput.write(mBuffer, 0, mLength);
}
mOutput.flush();
mOutput.close();
mInput.close();
}
// Open the database, so we can query it
public boolean openDataBase() throws SQLException {
String mPath = DB_PATH + DB_NAME;
mDataBase = SQLiteDatabase.openDatabase(mPath, null,
SQLiteDatabase.CREATE_IF_NECESSARY);
return mDataBase != null;
}
@Override
public synchronized void close() {
if (mDataBase != null)
mDataBase.close();
super.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
}
}
, ... 但它不起作用!您必须将数据库从资产路径复制到数据库路径,首先。@FrankN.Stein我发布了我的代码,但由于问题被标记为重复,我删除了我的代码。我会再发一次。现在这是一个很好的答案,+1.@FrankN.Stein谢谢你,伙计。经过一段时间,我已经在这方面成熟了,我尽力以最好的方式帮助初学者。但是如何在应用程序之外独立创建.db文件呢?