Android 需要帮助从资产文件夹复制数据吗
我想使用下面提供的代码将我的资产文件夹中的外部数据库添加到我的应用程序中。在旧版本的上运行应用程序时 android(如仿真器上的android 2.3.3)我收到以下错误: android.database.sqlite.SQLiteException:没有这样的表:android\u元数据 但该代码在较新版本上运行良好 代码如下:Android 需要帮助从资产文件夹复制数据吗,android,Android,我想使用下面提供的代码将我的资产文件夹中的外部数据库添加到我的应用程序中。在旧版本的上运行应用程序时 android(如仿真器上的android 2.3.3)我收到以下错误: android.database.sqlite.SQLiteException:没有这样的表:android\u元数据 但该代码在较新版本上运行良好 代码如下: public class MainDataBase extends SQLiteOpenHelper{ private static String DB_PA
public class MainDataBase extends SQLiteOpenHelper{
private static String DB_PATH = "/data/data/com.nony.dictionary/databases/";
private static String DB_NAME = "allwords.db";
private String TABLE_NAME ="ENGLISH";
private SQLiteDatabase myDataBase;
private final Context myContext;
public MainDataBase(Context context) {
super(context, DB_NAME, null, 1);
this.myContext = context;
}
public void createDataBase() throws IOException{
boolean dbExist = checkDataBase();
if(dbExist){
//do nothing - database already exist
}else{
//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.
SQLiteDatabase db = this.getReadableDatabase();
if (db.isOpen()){
db.close();
}
try {
copyDataBase();
} catch (IOException e) {
throw new Error("Error copying database");
}
}
}
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.
}
if(checkDB != null){
checkDB.close();
}
return checkDB != null ? true : false;
}
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;
//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();
}
public ArrayList<HashMap<String,String>> getalldatas()
{
String select=null;
ArrayList<HashMap<String,String>> allContacts = new ArrayList<HashMap<String,String>> ();
select ="SELECT * FROM "+TABLE_NAME +" ORDER BY ENGWORD" ;
SQLiteDatabase data = this.getReadableDatabase();
Cursor thecusor = data.rawQuery(select, null);
if(thecusor.moveToFirst())
{
do{
HashMap<String, String> createtheMap = new HashMap<String, String> ();
createtheMap.put("_ID", thecusor.getString(0));
createtheMap.put("ENGWORD", thecusor.getString(1));
// Log.d("gggg", thecusor.getString(0)+thecusor.getString(1)+thecusor.getString(2));
allContacts.add(createtheMap);
}while(thecusor.moveToNext());
}
return allContacts;
}
@Override
public void onCreate(SQLiteDatabase arg0) {
// TODO Auto-generated method stub
}
@Override
public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {
// TODO Auto-generated method stub
}
}您的数据库必须有一个名为android\u metadata的表。如果以编程方式创建数据库,将自动生成此特殊表 此表应包含两列: rowid您的主键整数 locale=将我们作为文本或其他区域设置代码
使用任何sqlite数据库打开程序打开资产文件夹中的allwords.db, 然后运行这个查询
CREATE TABLE android_metadata (locale TEXT);
提示:硬编码路径不好,请从context:thnx到d都获取数据库路径。这很神奇…我只是在我的sqlite浏览器上创建了d表,如前所述,它成功了。我将更改d硬编码too@user2694535很高兴帮助你,嗯……我想你也可以投票决定答案;