我开发了一款iPhone应用程序，现在我正在为Android克隆它。我在我的iPhone应用程序中使用了一个SQLite数据库，它有大约1000个预先填充的行。现在我想将此数据库导入Android应用程序。我已经在资产的数据库文件夹中添加了数据库。我已经检查了网上的一些教程并完成了以下编码：
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) {
}
}
但我收到以下错误：
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):
答案 0 :(得分：9)
确保此行已添加到AndroidManifest.xml文件中：
并且永远不要通过尝试捕获错误并且避免将任何东西放入捕获体中至少放置这个如果您不知道如何防止崩溃e.printStackTrace();