Reputation:
In an Android Application I want to get the Inputs from the user by means of three EditText views an then by pressing ta button I want to save them into my database,but when i press the Button an unexpected error makes my app close.how should I manage this?
Here is my Button:
//---btnInsert
Button btnInsert=(Button)findViewById(R.id.btnInsert);
btnInsert.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View arg0) {
DBAdapter db = new DBAdapter(DatabaseAndroid10.this);
long id;
String ISBN;
String Title;
String Publisher;
EditText txtISBN=(EditText)findViewById(R.id.txtISBN);
EditText txtTitle=(EditText)findViewById(R.id.txtTitle);
EditText txtPublisher=(EditText)findViewById(R.id.txtPublisher);
ISBN = txtISBN.getText().toString();
Title=txtTitle.getText().toString();
Publisher=txtPublisher.getText().toString();
id = db.insertTitle(
ISBN,Title,Publisher);
db.close();
}
});
And Here is my DBAdapter:
package com.example.databaseandroid10;
import android.content.ContentValues;
public class DBAdapter
{
public static final String KEY_ROWID = "_id";
public static final String KEY_ISBN = "isbn";
public static final String KEY_TITLE = "title";
public static final String KEY_PUBLISHER = "publisher";
private static final String TAG = "DBAdapter";
private static final String DATABASE_NAME = "books";
private static final String DATABASE_TABLE = "titles";
private static final int DATABASE_VERSION = 1;
private static final String DATABASE_CREATE =
"create table titles (_id integer primary key autoincrement, "
+ "isbn text not null, title text not null, "
+ "publisher text not null);";
private final Context context;
private DatabaseHelper DBHelper;
private SQLiteDatabase db;
public DBAdapter(Context ctx)
{
this.context = ctx;
DBHelper = new DatabaseHelper(context);
}
private static class DatabaseHelper extends SQLiteOpenHelper
{
DatabaseHelper(Context context)
{
super(context, DATABASE_NAME, null, DATABASE_VERSION);
}
@Override
public void onCreate(SQLiteDatabase db)
{
db.execSQL(DATABASE_CREATE);
}
@Override
public void onUpgrade(SQLiteDatabase db, int oldVersion,
int newVersion)
{
Log.w(TAG, "Upgrading database from version " + oldVersion
+ " to "
+ newVersion + ", which will destroy all old data");
db.execSQL("DROP TABLE IF EXISTS titles");
onCreate(db);
}
}
//---opens the database---
public DBAdapter open() throws SQLException
{
db = DBHelper.getWritableDatabase();
return this;
}
//---closes the database---
public void close()
{
DBHelper.close();
}
//---insert a title into the database---
public long insertTitle(String isbn, String title, String publisher)
{
ContentValues initialValues = new ContentValues();
initialValues.put(KEY_ISBN, isbn);
initialValues.put(KEY_TITLE, title);
initialValues.put(KEY_PUBLISHER, publisher);
return db.insert(DATABASE_TABLE, null, initialValues);
}
//---deletes a particular title---
public boolean deleteTitle(long rowId)
{
return db.delete(DATABASE_TABLE, KEY_ROWID +
"=" + rowId, null) > 0;
}
//---retrieves all the titles---
public Cursor getAllTitles()
{
return db.query(DATABASE_TABLE, new String[] {
KEY_ROWID,
KEY_ISBN,
KEY_TITLE,
KEY_PUBLISHER},
null,
null,
null,
null,
null);
}
//---retrieves a particular title---
public Cursor getTitle(long rowId) throws SQLException
{
Cursor mCursor =
db.query(true, DATABASE_TABLE, new String[] {
KEY_ROWID,
KEY_ISBN,
KEY_TITLE,
KEY_PUBLISHER
},
KEY_ROWID + "=" + rowId,
null,
null,
null,
null,
null);
if (mCursor != null) {
mCursor.moveToFirst();
}
return mCursor;
}
//---updates a title---
public boolean updateTitle(long rowId, String isbn,
String title, String publisher)
{
ContentValues args = new ContentValues();
args.put(KEY_ISBN, isbn);
args.put(KEY_TITLE, title);
args.put(KEY_PUBLISHER, publisher);
return db.update(DATABASE_TABLE, args,
KEY_ROWID + "=" + rowId, null) > 0;
}
}
Thanks In Advance
Upvotes: 0
Views: 2037
Reputation: 22291
You are not open database before insert value into database so this error will comes, so
Write below code line
db.open(); // For Open Database
before
id = db.insertTitle(ISBN,Title,Publisher); // For Insert value into Database
it will solve your problem.
Upvotes: 1
Reputation: 132982
PROBLEM ::
Yor are not opening database before adding new values to database
SOLUTION ::
Change your code for opeing database first :
db.open(); // open database here before inserting
id = db.insertTitle(ISBN,Title,Publisher);
db.close(); //close database here after inserting
Upvotes: 1