我有一个带有 tre 列的 sqlite 数据库:id、纬度、经度。纬度和经度是双倍的,例如 43.98722。当我在我的 android 设备中复制这个数据库时,经度和纬度的值变成 4.398722e+07 所以这可能不适用于我的应用程序。我怎么解决这个问题?也许是我的 dbhelper 通过 InputStream 和 OutputStream 复制一个外部数据库犯了这个错误?
问问题
177 次
2 回答
0
public class MyOpenHelper extends SQLiteOpenHelper{
private static String DB_PATH = "/data/data/pack.pullman/databases/";
private static String DB_NAME = "orari";
private SQLiteDatabase myDataBase;
private final Context myContext;
public MyOpenHelper(Context context) {
super(context, DB_NAME, null, 1);
if(android.os.Build.VERSION.SDK_INT >= 4.2){
DB_PATH = context.getApplicationInfo().dataDir + "/databases/";
} else {
DB_PATH = "/data/data/" + context.getPackageName() + "/databases/";
}
this.myContext = context;
}
public void createDataBase() throws IOException{
boolean dbExist = checkDataBase();
if(dbExist){
}else{
this.getReadableDatabase();
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_READWRITE);
}catch(SQLiteException e){
}
if(checkDB != null){
checkDB.close();
}
return checkDB != null ? true : false;
}
private void copyDataBase() throws IOException{
InputStream myInput = myContext.getAssets().open(DB_NAME);
String outFileName = DB_PATH + DB_NAME;
OutputStream myOutput = new FileOutputStream(outFileName);
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_READWRITE);
}
@Override
public synchronized void close() {
if(myDataBase != null)
myDataBase.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
}
}
于 2013-07-12T15:22:19.047 回答
0
public List<Coordinate> vediCoordinate(){
SQLiteDatabase db=oh.getReadableDatabase();
String c[]=new String[]{"lat","long","via"};
cu=db.query("linee", c, null, null, null, null, null);
int rows=cu.getCount();
LinkedList<Coordinate> risultato=new LinkedList<Coordinate>();
cu.moveToFirst();
for(int i=0;i<rows;i++){
risultato.add(i,new Coordinate(cu.getDouble(cu.getColumnIndex("lat")),cu.getDouble(cu.getColumnIndex("long")),cu.getString(cu.getColumnIndex("via"))));
cu.moveToNext();
}
cu.close();
return risultato;
}
于 2013-07-12T15:41:25.877 回答