SQLiteOpenHelper constructor problem
I Created SQLite Database in SQLiteBrowser. I want to refer it in android app so I put DB file in assets folder n used the following code to copy DB to App memory. M using eclipse for android app development.
But SQLiteOpenHelper constructor is giving error. The constructor DB_Import(DB_test1) is undefined
package com.example.DB_test1;
public class DB_test1 extends Activity{
/** Called when the activity is first created. */
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(sa开发者_开发技巧vedInstanceState);
setContentView(R.layout.main);
DB_Import my_Import;
//SQLiteDatabase myDb = null;
my_Import=new DB_Import(this);
try {
my_Import.createDatabase();
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
Following is another class file.
package com.example.DB_test1;
public class DB_Import extends SQLiteOpenHelper{
private final Context myContext;
String DB_PATH = "data/data/com.example.DB_test/databases/";
String DB_NAME = "Dict_temp";
private SQLiteDatabase myDatabase;
public DB_Import(Context context) {
super(context, "data/data/com.example.DB_test/databases/", null, 1);
this.myContext = context;
}
public void createDatabase()throws IOException{
// TODO Auto-generated method stub
boolean dbExist = checkDatabase(); ////////////////Check if database Exist
if (dbExist) {
//openDatabase();
}else {
this.getReadableDatabase();
try {
copyDatabase(); ///////////////Copies the database from assets to android
} catch (IOException e) {
// TODO Auto-generated catch block
throw new Error("Error copying database");
}
}
}
Try this code:
public class DataBaseHelper extends SQLiteOpenHelper{
private Context mycontext;
private String DB_PATH = "/data/data/gr.peos/databases/";
//private String DB_PATH = mycontext.getApplicationContext().getPackageName()+"/databases/";
private static String DB_NAME = "BLib.sqlite";//the extension may be .sqlite or .db
public SQLiteDatabase myDataBase;
/*private String DB_PATH = "/data/data/"
+ mycontext.getApplicationContext().getPackageName()
+ "/databases/";*/
public DataBaseHelper(Context context) throws IOException {
super(context,DB_NAME,null,1);
this.mycontext=context;
boolean dbexist = checkdatabase();
if(dbexist)
{
//System.out.println("Database exists");
opendatabase();
}
else
{
System.out.println("Database doesn't exist");
createdatabase();
}
}
public void createdatabase() throws IOException{
boolean dbexist = checkdatabase();
if(dbexist)
{
//System.out.println(" Database exists.");
}
else{
this.getReadableDatabase();
try{
copydatabase();
}
catch(IOException e){
throw new Error("Error copying database");
}
}
}
private boolean checkdatabase() {
//SQLiteDatabase checkdb = null;
boolean checkdb = false;
try{
String myPath = DB_PATH + DB_NAME;
File dbfile = new File(myPath);
//checkdb = SQLiteDatabase.openDatabase(myPath,null,SQLiteDatabase.OPEN_READWRITE);
checkdb = dbfile.exists();
}
catch(SQLiteException e){
System.out.println("Database doesn't exist");
}
return checkdb;
}
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("/data/data/gr.peos/databases/BLib.sqlite");
// transfer byte to inputfile to 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_READWRITE);
}
public synchronized void close(){
if(myDataBase != null){
myDataBase.close();
}
super.close();
}
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