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how sort listview filled with sqlite by last modified?

I'm absolute beginner.
I have a listview filled with sqlite table, I have two questions:
1- How can I sort this listview by last modified item ?
2- How can I make a button on my first page to open last modified item without going to listview !?
Here are my codes:
Its listview -
public class MainActivity extends ListActivity {
// Declare Variables
public static final String ROW_ID = "row_id";
private static final String TITLE = "title";
private ListView noteListView;
private CursorAdapter noteAdapter;
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
stopService(new Intent(MainActivity.this, MyService.class));
// Locate ListView
noteListView = getListView();
// Prepare ListView Item Click Listener
noteListView.setOnItemClickListener(viewNoteListener);
// Map all the titles into the ViewTitleNotes TextView
String[] from = new String[]{ TITLE };
int[] to = new int[]{ R.id.ViewTitleNotes };
// Create a SimpleCursorAdapter
noteAdapter = new SimpleCursorAdapter(MainActivity.this,
R.layout.list_zekr, null, from, to);
// Set the Adapter into SimpleCursorAdapter
setListAdapter(noteAdapter);
}
// Capture ListView item click
OnItemClickListener viewNoteListener = new OnItemClickListener() {
public void onItemClick(AdapterView<?> arg0, View arg1, int arg2, long arg3) {
// Open ViewNote activity
Intent viewnote = new Intent(MainActivity.this, CounterActivity.class);
viewnote.putExtra(ROW_ID, arg3);
startActivity(viewnote);
}
};
#Override
protected void onResume() {
super.onResume();
// Execute GetNotes Asynctask on return to MainActivity
new GetNotes().execute((Object[]) null);
}
#Override
protected void onStop() {
Cursor cursor = noteAdapter.getCursor();
// Deactivates the Cursor
if (cursor != null)
cursor.deactivate();
noteAdapter.changeCursor(null);
super.onStop();
}
// Create an options menu
#Override
public boolean onCreateOptionsMenu(Menu menu) {
// Menu Title
menu.add("ذکر جدید")
.setOnMenuItemClickListener(this.AddNewNoteClickListener)
.setShowAsAction(MenuItem.SHOW_AS_ACTION_IF_ROOM);
return super.onCreateOptionsMenu(menu);
}
// Capture menu item click
OnMenuItemClickListener AddNewNoteClickListener = new OnMenuItemClickListener() {
public boolean onMenuItemClick(MenuItem item) {
// Open AddEditNotes activity
Intent addnote = new Intent(MainActivity.this, AddEditNotes.class);
startActivity(addnote);
return false;
}
};
// GetNotes AsyncTask
public class GetNotes extends AsyncTask<Object, Object, Cursor> {
DatabaseConnector dbConnector = new DatabaseConnector(MainActivity.this);
#Override
protected Cursor doInBackground(Object... params) {
// Open the database
dbConnector.open();
return dbConnector.ListAllNotes();
}
#Override
protected void onPostExecute(Cursor result) {
noteAdapter.changeCursor(result);
// Close Database
dbConnector.close();
}
}
}
its my DatabaseConnector :
public class DatabaseConnector {
// Declare Variables
private static final String DB_NAME = "database";
private static final String TABLE_NAME = "tablenotes";
private static final String TITLE = "title";
private static final String ID = "_id";
private static final String NOTE = "note";
private static final String COUNTS = "counts";
private static final String LIMITS = "limits";
private static final int DATABASE_VERSION = 2;
private SQLiteDatabase database;
private DatabaseHelper dbOpenHelper;
public DatabaseConnector(Context context) {
dbOpenHelper = new DatabaseHelper(context, DB_NAME, null, DATABASE_VERSION);
}
// Open Database function
public void open() throws SQLException {
// Allow database to be in writable mode
database = dbOpenHelper.getWritableDatabase();
}
// Close Database function
public void close() {
if (database != null)
database.close();
}
// Create Database function
public void InsertNote(String title, String note, String counts, String limits) {
ContentValues newCon = new ContentValues();
newCon.put(TITLE, title);
newCon.put(NOTE, note);
newCon.put(COUNTS, counts);
newCon.put(LIMITS, limits);
open();
database.insert(TABLE_NAME, null, newCon);
close();
}
// Update Database function
public void UpdateNote(long id, String title, String note, String counts, String limits) {
ContentValues editCon = new ContentValues();
editCon.put(TITLE, title);
editCon.put(NOTE, note);
editCon.put(COUNTS, counts);
editCon.put(LIMITS, limits);
open();
database.update(TABLE_NAME, editCon, ID + "=" + id, null);
close();
}
// Delete Database function
public void DeleteNote(long id) {
open();
database.delete(TABLE_NAME, ID + "=" + id, null);
close();
}
// List all data function
public Cursor ListAllNotes() {
return database.query(TABLE_NAME, new String[]{ ID, TITLE }, null,
null, null, null, TITLE);
}
// Capture single data by ID
public Cursor GetOneNote(long id) {
return database.query(TABLE_NAME, null, ID + "=" + id, null, null,
null, null);
}
}
thanks in advance.
UPDATE !
Ok, I Created a Column in my table with name of "time"
and I can insert the time as INTEGER to it like this: 20160516100740
So now every Row of table has a time like that, NOW WHAT CAN I DO ?
Update !
Ok, I wrote this inside my list activity (MainActivity.java)
but its not working : (
public Cursor listAllSortedNotes() {
String selectQuery = "SELECT * FROM " + TABLE_NAME + " ORDER BY time DESC";
return database.rawQuery(selectQuery, null);

You need to add a field in the database which should be a date string (Sample: yyyy-MM-dd HH:mm:ss). And when you update the data, update it with current date and time. Then you can use select query to get the recent update data by using
SELECT *
FROM Table
ORDER BY datetime (dateColumn) DESC
In your case you can do something like this.
public Cursor listAllSortedNotes() {
String selectQuery = "SELECT * FROM "+ TABLE_NAME + " ORDER BY datetime(dateColumn) DESC";
return database.rawQuery(selectQuery, null);
}

Setting OnClickListener not working

I'm trying to create something like favorite thing in my app
I have made activity with restaurant which can be set as favorite, I've made imagebutton for making restaurant favorite and it's working, cause I have second activity where list is getting info from database and everything is ok. Titles match, adresses match cities too, so database should match too.
I have problem with changing OnClickListener, I want to use info from database to check if String called "database_name" is matching with any string from database.
There is code for it :
mDbHelper = new FeedReaderDbHelper(getApplicationContext());
final SQLiteDatabase db = mDbHelper.getWritableDatabase();
String[] selection = {FeedReaderContract.FeedEntry.COLUMN_NAME_DATABASE};
favoriteButton = (ImageButton) findViewById(R.id.favoriteRestaurant);
Cursor cursor = db.query(FeedReaderContract.FeedEntry.TABLE_NAME, selection,
null, null, null, null, null);
if(cursor.getCount() != 0) {
cursor.moveToFirst();
do {
if(cursor.getString(0).toLowerCase() == database_name.toLowerCase()){
favoriteButton.setBackground(getResources().getDrawable(R.drawable.favoritet));
isFavorite = 1;
}
} while (cursor.moveToNext());
}
It's changing background of this favorite button to filled heart, at least it's supposed to do so. In default it's not filled.
Then I'm changing onClickListener, code for it looks like this :
if(isFavorite == 0) {
favoriteButton.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
isntFavorite();
}
});
} else {
favoriteButton.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
isFavorite();
}
});
}
isFavorite look like this :
private void isFavorite() {
favoriteButton.setBackground(getResources().getDrawable(R.drawable.favoriteu));
String selection = FeedReaderContract.FeedEntry.COLUMN_NAME_DATABASE + " LIKE ?";
mDbHelper = new FeedReaderDbHelper(getApplicationContext());
SQLiteDatabase db = mDbHelper.getWritableDatabase();
String[] selectionArgs = new String[] { database_name };
db.delete(FeedReaderContract.FeedEntry.TABLE_NAME, selection, selectionArgs);
favoriteButton.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
isntFavorite();
}
});
}
And code for isntFavorite looks like this:
private void isntFavorite() {
favoriteButton.setBackground(getResources().getDrawable(R.drawable.favoritet));
mDbHelper = new FeedReaderDbHelper(getApplicationContext());
SQLiteDatabase db = mDbHelper.getWritableDatabase();
ContentValues values = new ContentValues();
values.put(FeedReaderContract.FeedEntry.COLUMN_NAME_TITLE, restaurantName);
values.put(FeedReaderContract.FeedEntry.COLUMN_NAME_ADRESS, restaurantAdress);
values.put(FeedReaderContract.FeedEntry.COLUMN_NAME_CITY, restaurantCity);
values.put(FeedReaderContract.FeedEntry.COLUMN_NAME_DATABASE, database_name);
long newRowId;
newRowId = db.insert(FeedReaderContract.FeedEntry.TABLE_NAME,
null, values);
favoriteButton.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
isFavorite();
}
});
}
The thing is that it's always changing onClickListener to isntFavorite and it's not changing image background to filled heart, even if there is matching data in database. I was trying to change matching title from database to title from activity, and I was sure that they're matching cause there was in list title with the same String as title from activity where I was trying to match them.

You don't need to change OnclickListener just create a boolean to save the state:
final boolean state = isFavorite == 0;
favoriteButton.setOnClickListener(new View.OnClickListener() {
boolean mState = state;
#Override
public void onClick(View v) {
if(mState)isntFavorite();
else isFavorite();
mState=!mState;
}
});
private void isFavorite() {
favoriteButton.setBackground(getResources().getDrawable(R.drawable.favoriteu));
String selection = FeedReaderContract.FeedEntry.COLUMN_NAME_DATABASE + " LIKE ?";
mDbHelper = new FeedReaderDbHelper(getApplicationContext());
SQLiteDatabase db = mDbHelper.getWritableDatabase();
String[] selectionArgs = new String[] { database_name };
db.delete(FeedReaderContract.FeedEntry.TABLE_NAME, selection, selectionArgs);
}
private void isntFavorite() {
favoriteButton.setBackground(getResources().getDrawable(R.drawable.favoritet));
mDbHelper = new FeedReaderDbHelper(getApplicationContext());
SQLiteDatabase db = mDbHelper.getWritableDatabase();
ContentValues values = new ContentValues();
values.put(FeedReaderContract.FeedEntry.COLUMN_NAME_TITLE, restaurantName);
values.put(FeedReaderContract.FeedEntry.COLUMN_NAME_ADRESS, restaurantAdress);
values.put(FeedReaderContract.FeedEntry.COLUMN_NAME_CITY, restaurantCity);
values.put(FeedReaderContract.FeedEntry.COLUMN_NAME_DATABASE, database_name);
long newRowId;
newRowId = db.insert(FeedReaderContract.FeedEntry.TABLE_NAME,
null, values);
}

How to check if database is empty in SQLite Android with DatabaseConnector class

I have a DatabaseConnector class where I want to check if the database is empty and then show an alert and a click on it will close the activity.
This is my DatabaseConnector class
public class DatabaseConnector {
// Declare Variables
private static final String DB_NAME = "MyNotes";
private static final String TABLE_NAME = "tablenotes";
private static final String TITLE = "title";
private static final String ID = "_id";
private static final String NOTE = "note";
private static final int DATABASE_VERSION = 2;
private SQLiteDatabase database;
private DatabaseHelper dbOpenHelper;
public static final String MAINCAT = "maincat";
public static final String SUBCAT = "subcat";
public DatabaseConnector(Context context) {
dbOpenHelper = new DatabaseHelper(context, DB_NAME, null,
DATABASE_VERSION);
}
// Open Database function
public void open() throws SQLException {
// Allow database to be in writable mode
database = dbOpenHelper.getWritableDatabase();
}
// Close Database function
public void close() {
if (database != null)
database.close();
}
// Create Database function
public void InsertNote(String title, String note , String maincat, String subcat) {
ContentValues newCon = new ContentValues();
newCon.put(TITLE, title);
newCon.put(NOTE, note);
newCon.put(MAINCAT, maincat);
newCon.put(SUBCAT, subcat);
open();
database.insert(TABLE_NAME, null, newCon);
close();
}
// Update Database function
public void UpdateNote(long id, String title, String note) {
ContentValues editCon = new ContentValues();
editCon.put(TITLE, title);
editCon.put(NOTE, note);
open();
database.update(TABLE_NAME, editCon, ID + "=" + id, null);
close();
}
// Delete Database function
public void DeleteNote(long id) {
open();
database.delete(TABLE_NAME, ID + "=" + id, null);
close();
}
// List all data function
//String selection = dbOpenHelper.MAINCAT + " = 'quiz'"
// +" AND " + dbOpenHelper.SUBCAT + " = 'test'";
// public Cursor ListAllNotes() {
// return database.query(TABLE_NAME, new String[] { ID, TITLE }, null,
// null, null, null, TITLE);
// }
public Cursor ListAllNotes(String selection) {
return database.query(TABLE_NAME, new String[] { ID, TITLE }, selection,
null, null, null, TITLE);
}
// Capture single data by ID
public Cursor GetOneNote(long id) {
return database.query(TABLE_NAME, null, ID + "=" + id, null, null,
null, null);
}
And here is the ListActivity wherein I want to close the Activity with an alert
public class dbMainactivty extends ListActivity {
// Declare Variables
public static final String ROW_ID = "row_id";
private static final String TITLE = "title";
private ListView noteListView;
private CursorAdapter noteAdapter;
#SuppressWarnings("deprecation")
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
Tracker t = ((AnalyticsSampleApp)this.getApplication()).getTracker(TrackerName.APP_TRACKER);
t.setScreenName("dbMainactivty");
t.send(new HitBuilders.AppViewBuilder().build());
// Locate ListView
noteListView = getListView();
// setContentView(R.layout.list_note);
//noteListView = (ListView) findViewById(R.id.listview);
// Prepare ListView Item Click Listener
noteListView.setOnItemClickListener(viewNoteListener);
// Map all the titles into the ViewTitleNotes TextView
String[] from = new String[] { TITLE };
int[] to = new int[] { R.id.ViewTitleNotes };
// Create a SimpleCursorAdapter
noteAdapter = new SimpleCursorAdapter(dbMainactivty.this,
R.layout.list_note, null, from, to);
// Set the Adapter into SimpleCursorAdapter
setListAdapter(noteAdapter);
}
// Capture ListView item click
OnItemClickListener viewNoteListener = new OnItemClickListener() {
public void onItemClick(AdapterView<?> arg0, View arg1, int arg2,
long arg3) {
// Open ViewNote activity
Intent viewnote = new Intent(dbMainactivty.this, ViewNote.class);
// Pass the ROW_ID to ViewNote activity
viewnote.putExtra(ROW_ID, arg3);
startActivity(viewnote);
}
};
#Override
protected void onResume() {
super.onResume();
// Execute GetNotes Asynctask on return to MainActivity
new GetNotes().execute((Object[]) null);
GoogleAnalytics.getInstance(dbMainactivty.this).reportActivityStart(this);
}
#Override
protected void onStop() {
Cursor cursor = noteAdapter.getCursor();
// Deactivates the Cursor
if (cursor != null)
cursor.deactivate();
noteAdapter.changeCursor(null);
super.onStop();
GoogleAnalytics.getInstance(dbMainactivty.this).reportActivityStop(this);
}
}
#Override
public boolean onOptionsItemSelected(MenuItem item) {
Intent i = null;
switch (item.getItemId()) {
case R.id.action_rate:
String webpage = "http://developer.android.com/index.html";
Intent intent2 = new Intent(Intent.ACTION_VIEW, Uri.parse(webpage));
startActivity(intent2);
overridePendingTransition(R.anim.slide_in, R.anim.slide_out);
case R.id.action_share:
i = new Intent();
i.setAction(Intent.ACTION_SEND);
//i.putExtra(Intent.EXTRA_TEXT, feed.getItem(pos).getTitle().toString()+ " to know the answer download http://developer.android.com/index.html");
i.setType("text/plain");
startActivity(i);
return true;
}
return super.onOptionsItemSelected(item);
};
// GetNotes AsyncTask
private class GetNotes extends AsyncTask<Object, Object, Cursor> {
DatabaseConnector dbConnector = new DatabaseConnector(dbMainactivty.this);
#Override
protected Cursor doInBackground(Object... params) {
// Open the database
dbConnector.open();
return dbConnector.ListAllNotes("maincat LIKE 'quiz' AND subcat LIKE 'test'");
}
#Override
protected void onPostExecute(Cursor result) {
noteAdapter.changeCursor(result);
// Close Database
dbConnector.close();
}
}
#Override
protected void onStart() {
super.onStart();
ConnectivityManager conMgr = (ConnectivityManager) getSystemService(Context.CONNECTIVITY_SERVICE);
if (conMgr.getActiveNetworkInfo() == null) {
AlertDialog.Builder builder = new AlertDialog.Builder(this);
builder.setMessage(
"Please check your Internet Connection.")
.setTitle("tilte")
.setCancelable(false)
.setPositiveButton("Exit",
new DialogInterface.OnClickListener() {
#Override
public void onClick(DialogInterface dialog,
int id) {
//loader.cancel(true);
finish();
}
});
AlertDialog alert = builder.create();
alert.show();
} else {
Cursor cursor = noteAdapter.getCursor();
if(cursor != null && cursor.getCount() > 0){
cursor.moveToFirst();
//do your action
//Fetch your data
GoogleAnalytics.getInstance(dbMainactivty.this).reportActivityStart(this);
Toast.makeText(getBaseContext(), "Yipeee!", Toast.LENGTH_SHORT).show();
}
else {
AlertDialog.Builder builder = new AlertDialog.Builder(this);
builder.setMessage(
"oops nothing pinned yet! ....")
.setTitle("title")
.setCancelable(false)
.setPositiveButton("Exit",
new DialogInterface.OnClickListener() {
#Override
public void onClick(DialogInterface dialog,
int id) {
//loader.cancel(true);
finish();
}
});
AlertDialog alert = builder.create();
alert.show();
Toast.makeText(getBaseContext(), "No records yet!", Toast.LENGTH_SHORT).show();
}
}
}
}
I am trying to check
cursor != null && cursor.getCount()>0 and if it turns false then show the alert that
nothing has been pinned yet
Should show up however even though if the cursor returns data the alert still shows up.

First step, take a look at the lifecycle of your activity: http://www.android-app-market.com/wp-content/uploads/2012/03/Android-Activity-Lifecycle.png
As you can see onResume() is called after onStart() which means that checking the cursor on the onStart() can not work.
Secondly you are starting an AsyncTask (GetNotes) on the onResume() method which means you are running a parallel thread at this point and can't check for the result after calling new GetNotes().execute((Object[]) null);
Your problem is you need to check the emptiness of your cursor (cursor != null && cursor.getCount()>0) AFTER the data is loader which mean after the AsyncTask has completed. In other words, move the check for emptiness on your cursor inside the onPostExecute(Cursor result) method.

Loader not loading data when sqlite data changes

I have a DialogFragment that I'm working on to display two spinners, side by side, one displays a list of drivers, the other a list of vehicles.
The data to populate these spinners is retrieved from a sqlite database. I am trying to use a LoaderManager to keep the spinners updated or in sync with the database tables, (drivers and vehicles).
When I add/delete/edit a record in either the drivers table or vehicles table in the database, the spinners don't get updated, the driver or vehicle remains unchanged in the spinner.
I'm not sure what I'm missing because I thought LoaderManager is supposed to keep the lists updated or in sync with the database tables automatically right?
I created a button called addDriverVehicle() which is supposed to allow the user to add another driver/vehicle in the future but for now I'm using it as a test to delete a driver to kind of simulate the database tables changing just so i can see if the spinner gets updated automatically but it's not happening. The record is being deleted but the spinner continues to show it.
public class DriverVehiclePickersDialogFragment extends DialogFragment implements LoaderManager.LoaderCallbacks<Cursor>, OnItemSelectedListener {
public static final String ARG_LISTENER_TYPE = "listenerType";
public static final String ARG_DIALOG_TYPE = "dialogType";
public static final String ARG_TITLE_RESOURCE = "titleResource";
public static final String ARG_SET_DRIVER = "setDriver";
public static final String ARG_SET_VEHICLE = "setVehicle";
private static final int DRIVERS_LOADER = 0;
private static final int VEHICLES_LOADER = 1;
private DriverVehicleDialogListener mListener;
// These are the Adapter being used to display the driver's and vehicle's data.
SimpleCursorAdapter mDriversAdapter, mVehiclesAdapter;
// Define Dialog view
private View mView;
// Store Driver and Vehicle Selected
private long[] mDrivers, mVehicles;
// Spinners Containing Driver and Vehicle List
private Spinner driversSpinner;
private Spinner vehiclesSpinner;
private static enum ListenerType {
ACTIVITY, FRAGMENT
}
public static enum DialogType {
DRIVER_SPINNER, VEHICLE_SPINNER, DRIVER_VEHICLE_SPINNER
}
public interface DriverVehicleDialogListener {
public void onDialogPositiveClick(long[] mDrivers, long[] mVehicles);
}
public DriverVehiclePickersDialogFragment() {
// Empty Constructor
Log.d("default", "default constructor ran");
}
public static DriverVehiclePickersDialogFragment newInstance(DriverVehicleDialogListener listener, Bundle dialogSettings) {
final DriverVehiclePickersDialogFragment instance;
if (listener instanceof Activity) {
instance = createInstance(ListenerType.ACTIVITY, dialogSettings);
} else if (listener instanceof Fragment) {
instance = createInstance(ListenerType.FRAGMENT, dialogSettings);
instance.setTargetFragment((Fragment) listener, 0);
} else {
throw new IllegalArgumentException(listener.getClass() + " must be either an Activity or a Fragment");
}
return instance;
}
private static DriverVehiclePickersDialogFragment createInstance(ListenerType listenerType, Bundle dialogSettings) {
DriverVehiclePickersDialogFragment fragment = new DriverVehiclePickersDialogFragment();
if (!dialogSettings.containsKey(ARG_LISTENER_TYPE)) {
dialogSettings.putSerializable(ARG_LISTENER_TYPE, listenerType);
}
if (!dialogSettings.containsKey(ARG_DIALOG_TYPE)) {
dialogSettings.putSerializable(ARG_DIALOG_TYPE, DialogType.DRIVER_VEHICLE_SPINNER);
}
if (!dialogSettings.containsKey(ARG_TITLE_RESOURCE)) {
dialogSettings.putInt(ARG_TITLE_RESOURCE, 0);
}
fragment.setArguments(dialogSettings);
return fragment;
}
#Override
public void onAttach(Activity activity) {
super.onAttach(activity);
// Find out how to get the DialogListener instance to send the callback events to
Bundle args = getArguments();
ListenerType listenerType = (ListenerType) args.getSerializable(ARG_LISTENER_TYPE);
switch (listenerType) {
case ACTIVITY: {
// Send callback events to the hosting activity
mListener = (DriverVehicleDialogListener) activity;
break;
}
case FRAGMENT: {
// Send callback events to the "target" fragment
mListener = (DriverVehicleDialogListener) getTargetFragment();
break;
}
}
}
#Override
public void onActivityCreated(Bundle savedInstanceState) {
// TODO Auto-generated method stub
super.onActivityCreated(savedInstanceState);
Button btnAddDriverVehicle = (Button) mView.findViewById(R.id.addDriverVehicleButton);
btnAddDriverVehicle.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
DatabaseHelper1 mOpenHelper = new DatabaseHelper1(getActivity());
try {
SQLiteDatabase db = mOpenHelper.getWritableDatabase();
db.delete("drivers", " driver_number = 70", null);
} catch (SQLException e) {
}
}
});
}
#Override
public Dialog onCreateDialog(Bundle savedInstanceState) {
super.onSaveInstanceState(savedInstanceState);
Bundle args = getArguments();
int titleResource = args.getInt(ARG_TITLE_RESOURCE);
DialogType dialogType = (DialogType) args.getSerializable(ARG_DIALOG_TYPE);
if (args.containsKey(ARG_SET_DRIVER)) {
mDrivers = args.getLongArray(ARG_SET_DRIVER);
}
if (args.containsKey(ARG_SET_VEHICLE)) {
mVehicles = args.getLongArray(ARG_SET_VEHICLE);
}
mView = LayoutInflater.from(getActivity()).inflate(R.layout.driver_vehicle_dialog, null);
if ((dialogType == DialogType.DRIVER_SPINNER) || (dialogType == DialogType.DRIVER_VEHICLE_SPINNER)) {
driversSpinner = (Spinner) mView.findViewById(R.id.driversSpinner);
vehiclesSpinner = (Spinner) mView.findViewById(R.id.vehiclesSpinner);
driversSpinner.setVisibility(View.VISIBLE);
mDriversAdapter = new SimpleCursorAdapter(getActivity(), R.layout.driver_listview_row, null, new String[] { ConsoleContract.Drivers.DRIVER_NUMBER,
ConsoleContract.Drivers.DRIVER_NAME }, new int[] { R.id.driver_number, R.id.driver_name }, 0);
driversSpinner.setAdapter(mDriversAdapter);
driversSpinner.setOnItemSelectedListener(this);
}
if ((dialogType == DialogType.VEHICLE_SPINNER) || (dialogType == DialogType.DRIVER_VEHICLE_SPINNER)) {
vehiclesSpinner.setVisibility(View.VISIBLE);
mVehiclesAdapter = new SimpleCursorAdapter(getActivity(), R.layout.vehicle_listview_row, null, new String[] { ConsoleContract.Vehicles.VEHICLE_NUMBER,
ConsoleContract.Vehicles.VEHICLE_VIN }, new int[] { R.id.vehicle_number, R.id.vehicle_vin }, 0);
vehiclesSpinner.setAdapter(mVehiclesAdapter);
vehiclesSpinner.setOnItemSelectedListener(this);
}
// Prepare the loader. Either re-connect with an existing one, or start a new one.
getLoaderManager().initLoader(DRIVERS_LOADER, null, this);
getLoaderManager().initLoader(VEHICLES_LOADER, null, this);
AlertDialog.Builder builder = new AlertDialog.Builder(getActivity());
builder.setView(mView);
if (titleResource == 0) {
builder.setMessage("Select Driver and Vehicle");
} else {
builder.setMessage(getString(titleResource));
}
builder.setPositiveButton(android.R.string.ok, new OnClickListener() {
public void onClick(DialogInterface dialog, int which) {
mListener.onDialogPositiveClick(mDrivers, mVehicles);
}
});
builder.setNegativeButton(android.R.string.cancel, null);
return builder.create();
}
private static class DatabaseHelper1 extends SQLiteOpenHelper {
private static final String DATABASE_NAME = "test.db";
private static final int DATABASE_VERSION = 1;
DatabaseHelper1(Context context) {
super(context, DATABASE_NAME, null, DATABASE_VERSION);
}
#Override
public void onCreate(SQLiteDatabase db) {
}
#Override
public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {
}
}
#Override
public void onDetach() {
super.onDetach();
mListener = null;
}
// These are the Contacts rows that we will retrieve.
static final String[] DRIVERS_SUMMARY_PROJECTION = new String[] { ConsoleContract.Drivers._ID, ConsoleContract.Drivers.DRIVER_ID, ConsoleContract.Drivers.DRIVER_NUMBER,
ConsoleContract.Drivers.DRIVER_NAME };
static final String[] VEHICLES_SUMMARY_PROJECTION = new String[] { ConsoleContract.Vehicles._ID, ConsoleContract.Vehicles.VEHICLE_ID, ConsoleContract.Vehicles.VEHICLE_NUMBER,
ConsoleContract.Vehicles.VEHICLE_VIN };
#Override
public Loader<Cursor> onCreateLoader(int id, Bundle args) {
// This is called when a new Loader needs to be created. This
// sample only has one Loader, so we don't care about the ID.
// First, pick the base URI to use depending on whether we are
// currently filtering.
Uri baseUri = null;
String select = null, sortOrder = null;
String[] projection = null;
switch (id) {
case DRIVERS_LOADER:
baseUri = ConsoleContract.Drivers.CONTENT_URI;
select = "((" + Drivers.DRIVER_NAME + " NOT NULL) AND (" + Drivers.DRIVER_NAME + " != '' ))";
sortOrder = Drivers.DRIVER_NUMBER;
projection = DRIVERS_SUMMARY_PROJECTION;
break;
case VEHICLES_LOADER:
baseUri = ConsoleContract.Vehicles.CONTENT_URI;
select = "((" + Vehicles.VEHICLE_NUMBER + " NOT NULL) AND (" + Vehicles.VEHICLE_NUMBER + " != '' ))";
sortOrder = Vehicles.VEHICLE_NUMBER;
projection = VEHICLES_SUMMARY_PROJECTION;
break;
}
return new CursorLoader(getActivity(), baseUri, projection, select, null, sortOrder);
}
#Override
public void onLoadFinished(Loader<Cursor> loader, Cursor data) {
// Swap the new cursor in. (The framework will take care of closing the
// old cursor once we return.)
int id = loader.getId();
MatrixCursor newCursor = null;
switch (id) {
case DRIVERS_LOADER:
newCursor = new MatrixCursor(DRIVERS_SUMMARY_PROJECTION);
break;
case VEHICLES_LOADER:
newCursor = new MatrixCursor(VEHICLES_SUMMARY_PROJECTION);
break;
}
newCursor.addRow(new String[] { "0", "0", "", "" });
Cursor[] cursors = { newCursor, data };
Cursor mergedCursor = new MergeCursor(cursors);
switch (id) {
case DRIVERS_LOADER:
mDriversAdapter.swapCursor(mergedCursor);
break;
case VEHICLES_LOADER:
mVehiclesAdapter.swapCursor(mergedCursor);
break;
}
}
#Override
public void onLoaderReset(Loader<Cursor> loader) {
// This is called when the last Cursor provided to onLoadFinished()
// above is about to be closed. We need to make sure we are no
// longer using it.
int id = loader.getId();
switch (id) {
case DRIVERS_LOADER:
mDriversAdapter.swapCursor(null);
break;
case VEHICLES_LOADER:
mVehiclesAdapter.swapCursor(null);
break;
}
}
#Override
public void onItemSelected(AdapterView<?> parent, View view, int pos, long id) {
if (parent.getId() == R.id.driversSpinner) {
mDriver = id;
} else {
mVehicle = id;
}
}
#Override
public void onNothingSelected(AdapterView<?> parent) {
}
}

Make sure in your ContentProvider to call the notifyChange() method inside the insert, delete and update methods.
Here a snippet taken from Grokking Android Blog
public Uri insert(Uri uri, ContentValues values) {
if (URI_MATCHER.match(uri) != LENTITEM_LIST) {
throw new IllegalArgumentException("Unsupported URI for insertion: " + uri);
}
long id = db.insert(DBSchema.TBL_ITEMS, null, values);
if (id > 0) {
// notify all listeners of changes and return itemUri:
Uri itemUri = ContentUris.withAppendedId(uri, id);
getContext().getContentResolver().notifyChange(itemUri, null);
return itemUri;
}
// s.th. went wrong:
throw new SQLException("Problem while inserting into " + DBSchema.TBL_ITEMS + ", uri: " + uri); // use another exception here!!!
}
Conversely your Loader won't "heard" DB changes.

#rciovati's answer is good to me. But for me,I used Cursor Loader in my list view so it also need at query method in My ContentProvider.
In your ContentProvider class, query method also need to call notify after query like the code below-
#Override
public Cursor query(Uri uri, String[] projection, String selection, String[] selectionArgs, String sort) {
SQLiteQueryBuilder queryBuilder=new SQLiteQueryBuilder();
Cursor cursor=queryBuilder.query(dbHelper.getReadableDatabase(),
projection,
selection,
selectionArgs,
null,
null,
sort);
cursor.setNotificationUri(getContext().getContentResolver(), uri);
return cursor;
}

retrieve the ID (in the database) of the element the user have clicked on a listview

this is what i have done, to retrieve the id but it says that getIndexColumn is not defined in the cursor... what i'm doing wrong?
protected void onListItemClick(ListView l, View v, int position, long id) {
Cursor data = (Cursor)l.getItemAtPosition(position);
String cat = Cursor.getString(Cursor.getIndexColumn(MySQLiteHelper.COLUMN_ID));
Intent myIntent = new Intent(MainActivity.this, sondaggioActivity.class);
myIntent.putExtra("categoriaId", cat);
MainActivity.this.startActivity(myIntent);
}
this is the category class:
public class categorie {
private long id;
private String nome;
private long preferita;
public long getId() {
return id;
}
public void setId(long id) {
this.id = id;
}
public String getNome() {
return nome;
}
public void setNome(String nome) {
this.nome = nome;
}
public long getPreferita() {
return preferita;
}
public void setPreferita(long preferita) {
this.preferita = preferita;
}
// Will be used by the ArrayAdapter in the ListView
#Override
public String toString() {
return nome;
}
}
and this is the datasource:
public class pollDataSource {
// Database fields
private SQLiteDatabase database;
private MySQLiteHelper dbHelper;
private String[] allCategorieColumns = { MySQLiteHelper.COLUMN_ID,
MySQLiteHelper.COLUMN_PREF, MySQLiteHelper.COLUMN_NOME };
private String[] allSondaggiColumns = { MySQLiteHelper.COLUMN_ID,
MySQLiteHelper.COLUMN_CATID, MySQLiteHelper.COLUMN_DOMANDA };
private String[] allRisposteColumns = { MySQLiteHelper.COLUMN_ID,
MySQLiteHelper.COLUMN_SONDID, MySQLiteHelper.COLUMN_RISPOSTA,
MySQLiteHelper.COLUMN_SELEZIONATA };
public pollDataSource(Context context) {
dbHelper = new MySQLiteHelper(context);
}
public void open() throws SQLException {
database = dbHelper.getWritableDatabase();
}
public void close() {
dbHelper.close();
}
public categorie createCategoria(String categoria) {
ContentValues values = new ContentValues();
values.put(MySQLiteHelper.COLUMN_NOME, categoria);
values.put(MySQLiteHelper.COLUMN_PREF, 0);
long insertId = database.insert(MySQLiteHelper.TABLE_CATEGORIE, null,
values);
Cursor cursor = database.query(MySQLiteHelper.TABLE_CATEGORIE,
allCategorieColumns, MySQLiteHelper.COLUMN_ID + " = " + insertId, null,
null, null, null);
cursor.moveToFirst();
categorie newCategoria = cursorToCategorie(cursor);
cursor.close();
return newCategoria;
}
public void deleteCategoria(categorie categoria) {
long id = categoria.getId();
System.out.println("Categoria cancellata, id: " + id);
database.delete(MySQLiteHelper.TABLE_CATEGORIE, MySQLiteHelper.COLUMN_ID
+ " = " + id, null);
}
public sondaggi createSondaggio(String domanda, int catid) {
ContentValues values = new ContentValues();
values.put(MySQLiteHelper.COLUMN_DOMANDA, domanda);
values.put(MySQLiteHelper.COLUMN_CATID, catid);
long insertId = database.insert(MySQLiteHelper.TABLE_SONDAGGI, null,
values);
Cursor cursor = database.query(MySQLiteHelper.TABLE_SONDAGGI,
allSondaggiColumns, MySQLiteHelper.COLUMN_ID + " = " + insertId, null,
null, null, null);
cursor.moveToFirst();
sondaggi newSondaggio = cursorToSondaggi(cursor);
cursor.close();
return newSondaggio;
}
public void deleteSondaggio(sondaggi sondaggio) {
long id = sondaggio.getId();
System.out.println("Sondaggio cancellato, id: " + id);
database.delete(MySQLiteHelper.TABLE_SONDAGGI, MySQLiteHelper.COLUMN_ID
+ " = " + id, null);
}
public Cursor getAllCategorie() {
List<categorie> categorie = new ArrayList<categorie>();
Cursor cursor = database.query(MySQLiteHelper.TABLE_CATEGORIE,
allCategorieColumns, null, null, null, null, null);
cursor.moveToFirst();
while (!cursor.isAfterLast()) {
categorie categoria = cursorToCategorie(cursor);
categorie.add(categoria);
cursor.moveToNext();
}
// Make sure to close the cursor
// cursor.close();
return cursor;
}
private categorie cursorToCategorie(Cursor cursor) {
categorie categorie = new categorie();
categorie.setId(cursor.getLong(0));
categorie.setPreferita(cursor.getLong(1));
categorie.setNome(cursor.getString(2));
return categorie;
}
private sondaggi cursorToSondaggi(Cursor cursor) {
sondaggi sondaggi = new sondaggi();
sondaggi.setId(cursor.getLong(0));
sondaggi.setDomanda(cursor.getString(1));
sondaggi.setCatid(cursor.getLong(2));
return sondaggi;
}
}
the main activity:
public class MainActivity extends ListActivity {
private pollDataSource datasource;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
datasource = new pollDataSource(this);
datasource.open();
Cursor values = datasource.getAllCategorie();
String[] categorieColumns =
{
MySQLiteHelper.COLUMN_NOME // Contract class constant containing the word column name
};
int[] mWordListItems = { R.id.categoria_label };
SimpleCursorAdapter adapter = new SimpleCursorAdapter(
getApplicationContext(), // The application's Context object
R.layout.single_list_item, // A layout in XML for one row in the ListView
values, // The result from the query
categorieColumns, // A string array of column names in the cursor
mWordListItems, // An integer array of view IDs in the row layout
0); // Flags (usually none are needed)
setListAdapter(adapter);
}
public void onClick(View view) {
switch (view.getId()) {
case R.id.add:
datasource.createCategoria("peppe");
break;
}
}
#Override
protected void onListItemClick(ListView l, View v, int position, long id) {
Intent myIntent = new Intent(MainActivity.this, sondaggioActivity.class);
myIntent.putExtra("categoriaId", id);
MainActivity.this.startActivity(myIntent);
//Toast.makeText(this, selection, Toast.LENGTH_LONG).show();
}
#Override
public boolean onCreateOptionsMenu(Menu menu) {
// Inflate the menu; this adds items to the action bar if it is present.
getMenuInflater().inflate(R.menu.main, menu);
return true;
}

I assume you have an activity with a list of categories, and onClick of a particular item you want to launch new activity with details of that Item.
I suggest you when you launch the listScreen, query all/some items and maintaine an arrayList of items and save that in some singleton class, then onClick of a particular item pass that index to detail screen via intent.putExtra("index", position) and on detail Screen get that index via getIntent().getIntExtra("index", -1) .now get details of that particular index from arraylist saved in singleton class.
This approach will reduce cost of querying every time from database and data will be available easily.

Change
Cursor data = (Cursor)l.getItemAtPosition(position);
String cat = Cursor.getString(Cursor.getIndexColumn(MySQLiteHelper.COLUMN_ID));
to
Cursor data = (Cursor)l.getItemAtPosition(position);
Long clid = data.getLong(data.getIndexColumn(MySQLiteHelper.COLUMN_ID));
String cat=Long.toString(clid);

those two lines:
Cursor data = (Cursor)l.getItemAtPosition(position);
String cat = Cursor.getString(Cursor.getIndexColumn(MySQLiteHelper.COLUMN_ID));
makes absolutely no sense at all! If you're using a CursorAdapter why are you creating an array of objects? If you're using a ArrayAdapter why are you getting data from cursor?
Also, Cursor don't have any static methods to be called like that. That shouldn't even compile.
If you're using a CursorAdater (or some class that extend it) you the id is passed to you long id here protected void onListItemClick(ListView l, View v, int position, long id)