I created a sample application using android sqlite database, my requirements are How can i use Sqlite database in my android activity? (kindly noitce this link). I used the following code to do this,
MainClass.java
public class MainClass extends Activity implements OnClickListener {
Button NUM_INPUT;
EditText enter_NUM;
int number;
DatabaseHandler db = new DatabaseHandler(this);
@Override
protected void onCreate(Bundle savedInstanceState) {
// TODO Auto-generated method stub
super.onCreate(savedInstanceState);
setContentView(R.layout.sai_answers_home);
NUM_INPUT = (Button) findViewById(R.id.answerButton);
enter_NUM = (EditText) findViewById(R.id.saiAnssersEditText);
NUM_INPUT.setOnClickListener(this);
}
@Override
public void onClick(View v) {
// TODO Auto-generated method stub
if (v.getId() == R.id.answerButton) {
number = Integer.parseInt(this.enter_NUM.getText().toString());
// /System.out.println("EDITTEXTVALUE" + number);
Log.d("Reading: ", "Reading all contacts..");
List<Contact> contacts = db.getAllContacts(number);
for (Contact cn : contacts) {
String log = "Id: " + cn.getID() + " ,Name: " + cn.getName();
// Writing Contacts to log
Log.d("Name: ", log);
}
db.close();
}
}
}
DataBaseHandler.java
public class DatabaseHandler extends SQLiteOpenHelper {
// The Android's default system path of your application database.
private static String DB_PATH = "/data/data/com.sqlite.example/databases/";
private static String DB_NAME = "answers";
private SQLiteDatabase myDataBase;
private final Context myContext;
String myPath;
/**
* Constructor Takes and keeps a reference of the passed context in order to
* access to the application assets and resources.
*
* @param context
*/
public DatabaseHandler(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() 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.
this.getReadableDatabase();
try {
copyDataBase();
} catch (IOException e) {
throw new Error("Error copying database");
}
}
}
/**
* 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 {
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;
}
/**
* 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;
// 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
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) {
}
// Add your public helper methods to access and get content from the
// database.
// You could return cursors by doing "return myDataBase.query(....)" so it'd
// be easy
// to you to create adapters for your views.
public List<Contact> getAllContacts(int muNumber) {
List<Contact> contactList = new ArrayList<Contact>();
// Select All Query
String selectQuery = "SELECT * FROM ANSWER WHERE ID= " + muNumber;
System.out.println("QUERY STRING IS......>>>>>> " + selectQuery);
SQLiteDatabase db = this.getWritableDatabase();
Cursor cursor = db.rawQuery(selectQuery, null);
// looping through all rows and adding to list
if (cursor.moveToFirst()) {
do {
Contact contact = new Contact();
contact.setID(Integer.parseInt(cursor.getString(0)));
contact.setName(cursor.getString(1));
// contact.setPhoneNumber(cursor.getString(2));
// Adding contact to list
contactList.add(contact);
} while (cursor.moveToNext());
}
// return contact list
return contactList;
}
}
answers.db
When i execute this code i got Error, “android.database.sqlite.SQLiteException: no such table: ANSWER: , while compiling: SELECT * FROM ANSWER WHERE ID= 3”. My exact requirement is, when click the Button in MainActivity class, the entered value is passed to database. Finally search into the database and return the corresponding values present in database. For example i entered 2 and click the button, from the database i will get “Orange” how can i achieve this. Thanks in advance.
in the select query you have mentioned “SELECT * FROM ANSWER WHERE ID=”
But you have to mention as ” “SELECT * FROM answer WHERE ID”
Because table name is answer not ANSWER