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Update ListView in Fragment after AlertDialog dismiss

I have a Fragment containing ListView. I'm adding some values to the database with a dialog and I want to update this ListView after dialog is dismissed. Also, when I change the tab, the ListView is not updated but when the application is turned on and off, the ListView is updated.
Fragment and Dialog classes are as follows:
Fragment:
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
// Inflate the layout for this fragment
View rootView = inflater.inflate(R.layout.fragment_teams, container, false);
listViewTeams = rootView.findViewById(R.id.listView_teams);
TeamDatabase teamDatabase = new TeamDatabase(getContext());
teamDatabase.open();
arrayListTeam = teamDatabase.getAllTeams();
teamDatabase.close();
int resID = R.layout.team_list_item;
teamListArrayAdapter = new TeamListArrayAdapter(getContext(), resID, arrayListTeam);
listViewTeams.setAdapter(teamListArrayAdapter);
return rootView;
}
Dialog onClick Method:
#Override
public void onClick(View view) {
int id = view.getId();
switch (id){
case R.id.button_alertDialogAddTeam_cancel:
this.dismiss();
break;
case R.id.button_alertDialogAddTeam_ok:
Team team = new Team();
team.setName(editTextTeamName.getText().toString());
team.setCode(editTextTeamCode.getText().toString());
TeamDatabase teamDatabase = new TeamDatabase(getContext());
teamDatabase.open();
if(teamDatabase.addNewTeam(team)) {
Toast.makeText(getContext(), team.getCode() + " - " +
team.getName() + " was added successfully", Toast.LENGTH_SHORT).show();
}
this.dismiss();
break;
}
}
TeamDatabase class:
public static final String TABLE_NAME = "team";
private static final String KEY_ID = "id";
private static final String KEY_NAME = "name";
private static final String KEY_CODE = "code";
private static final String KEY_EMBLEM = "emblem";
private Context context;
public static final String CREATE_TABLE = "CREATE TABLE "+
TABLE_NAME + " ("+
KEY_ID + " INTEGER NOT NULL PRIMARY KEY AUTOINCREMENT UNIQUE, "+
KEY_NAME + " TEXT NOT NULL, "+
KEY_CODE + " TEXT NOT NULL, " +
KEY_EMBLEM + " TEXT);";
public TeamDatabase(Context context) {
super(context);
this.context = context;
}
public boolean addNewTeam(Team team){
ContentValues contentValues = new ContentValues();
contentValues.put(KEY_NAME, team.getName());
contentValues.put(KEY_CODE, team.getCode());
return db.insert(TABLE_NAME, null, contentValues) > 0;
}
public ArrayList<Team> getAllTeams()
{
ArrayList<Team> teams = new ArrayList<Team>();
Cursor cursor = db.query(TABLE_NAME, new String[]{KEY_ID,
KEY_NAME,
KEY_CODE}, null, null, null, null, null);
while(cursor.moveToNext()) {
Team team = new Team();
team.setId(cursor.getInt(cursor.getColumnIndex(KEY_ID)));
team.setName(cursor.getString(cursor.getColumnIndex(KEY_NAME)));
team.setCode(cursor.getString(cursor.getColumnIndex(KEY_CODE)));
teams.add(team);
}
return teams;
}
DatabaseHelper class:
private static final String DATABASE_NAME = "fixtureCreator.db";
private static final int DATABASE_VERSION = 1;
public SQLiteDatabase db;
public DatabaseHelper(Context context){
super(context, DATABASE_NAME, null, DATABASE_VERSION);
}
#Override
public void onCreate(SQLiteDatabase sqLiteDatabase) {
sqLiteDatabase.execSQL(TeamDatabase.CREATE_TABLE);
}
#Override
public void onUpgrade(SQLiteDatabase sqLiteDatabase, int oldVersion, int newVersinon) {
Log.w("TaskDBAdapter", "Upgrading from version " +
oldVersion + " to " + newVersinon + ", which will destroy all old data");
sqLiteDatabase.execSQL("DROP TABLE IF EXISTS " + TeamDatabase.TABLE_NAME);
onCreate(sqLiteDatabase);
}
public DatabaseHelper open() throws SQLException {
try{
db = this.getWritableDatabase();
}catch (SQLException e){
db = this.getReadableDatabase();
}
return this;
}
public void close(){
db.close();
}

On clicking the item in your first Activity, start your second Activity with startActivityForResult()
And then in Second Activity, after dismissing the dialog,in onClick of that button call,
intent.putExtra("new data", "item text");
setResult(RESULT_OK, intent);
finish();
Now you come back to your first Activity and here you have to implement onActivityResult() callback.
You can extract data from that intent's extras and set that respective item in your array and call notifyDataSetChanged().
This is ideally how you should be doing it.

The problem can be solved using fetching the data after saving it each time you click on the Dialog and then call notifyDataSetChanged() on your adapter. However, there is more elegant way of achieving this kind of behaviour, which will solve both of your problems using content observer.
In case of having a content observer in your database table you need to declare a URI first which references your table.
public static final Uri DB_TABLE_TEAM_URI = Uri
.parse("sqlite://" + Constants.ApplicationPackage + "/" + DB_TABLE_TEAM);
// DB_TABLE_TEAM refers to the database table that you have for storing teams.
Now in your addNewTeam function you need to do the following.
public boolean addNewTeam(Team team) {
// .. Save the team in database
// Notify the observer about the change in the content
context.getContentResolver().notifyChange(DBConstants.DB_TABLE_TEAM_URI, null);
}
You need to call notifyChange() function whenever you add or update an entry in your team table.
Now in your Activity or Fragment you need to register your observer on your cursor having the team data fetched from your team table.
cursor = teamDatabase.getAllTeamsInCursor();
this.registerContentObserver(cursor, DBConstants.DB_TABLE_TEAM_URI);
Now populate your ListView using the cursor by passing it to your adapter of ListView. The list will be updated automatically once a new data has been inserted in your team table.
Update
Modify the addNewTeam function in your TeamDatabase class as follows.
public static final Uri DB_TABLE_TEAM_URI = Uri
.parse("sqlite://" + Constants.ApplicationPackage + "/" + DB_TABLE_TEAM);
public boolean addNewTeam(Team team){
ContentValues contentValues = new ContentValues();
contentValues.put(KEY_NAME, team.getName());
contentValues.put(KEY_CODE, team.getCode());
boolean success = db.insert(TABLE_NAME, null, contentValues) > 0;
context.getContentResolver().notifyChange(DBConstants.DB_TABLE_TEAM_URI, null);
return success;
}
To implement the functionalities with LoaderCallbacks you first need to implement the interface of LoaderCallbacks in your Fragment. So the declaration of your Fragment will look like.
public class TeamsFragment extends Fragment implements LoaderManager.LoaderCallbacks<Cursor> {
// .... Code
}
Now you need to override the functions that comes along with the interface of LoaderCallbacks.
#Override
public Loader<Cursor> onCreateLoader(int id, Bundle args) {
return new SQLiteCursorLoader(getActivity()) {
#Override
public Cursor loadInBackground() {
// Initialize your database
TeamDatabase teamDatabase = new TeamDatabase(getActivity());
Cursor cursor = teamDatabase.getAllTeams();
if (cursor != null) {
// Register the content observer here
this.registerContentObserver(cursor, DBConstants.DB_TABLE_TEAM_URI);
}
return cursor;
}
};
}
#Override
public void onLoadFinished(Loader<Cursor> loader, Cursor data) {
// Set the cursor in your adapter. Handle null values in your setCursor function in your adapter. The cursor might return null when the table is empty.
teamAdapter.setCursor(cursor);
teamAdapter.notifyDataSetChanged();
}
#Override
public void onLoaderReset(Loader<Cursor> loader) {
}
Now in your onCreateView function in the Fragment, you need to initiate the loader to fetch data from the table.
getLoaderManager().initLoader(0, null, this).forceLoad();
And destroy the loader and un-register the receiver in the onDestroyView function.
#Override
public void onDestroyView() {
getLoaderManager().destroyLoader(0);
super.onDestroyView();
}
I was missing the SQLiteCursorLoader class to be added here.
package com.wooz.observer.databases;
import android.content.ContentResolver;
import android.content.Context;
import android.database.ContentObserver;
import android.database.Cursor;
import android.net.Uri;
import android.os.Handler;
import android.support.v4.content.AsyncTaskLoader;
import android.support.v4.content.Loader;
import java.io.FileDescriptor;
import java.io.PrintWriter;
import java.util.Arrays;
public abstract class SQLiteCursorLoader extends AsyncTaskLoader<Cursor> {
private final ForceLoadContentObserver mObserver;
private Uri mUri;
private String[] mProjection;
private String mSelection;
private String[] mSelectionArgs;
private String mSortOrder;
private Cursor mCursor;
/* Runs on a worker thread */
#Override
public abstract Cursor loadInBackground();
/**
* Registers an observer to get notifications from the content provider
* when the cursor needs to be refreshed.
*/
public void registerContentObserver(Cursor cursor, Uri observerUri) {
cursor.registerContentObserver(mObserver);
cursor.setNotificationUri(getContext().getContentResolver(), observerUri);
}
/* Runs on the UI thread */
#Override
public void deliverResult(Cursor cursor) {
try {
if (isReset()) {
// An async query came in while the loader is stopped
if (cursor != null) {
cursor.close();
}
return;
}
Cursor oldCursor = mCursor;
mCursor = cursor;
if (isStarted()) {
super.deliverResult(cursor);
}
if (oldCursor != null && oldCursor != cursor && !oldCursor.isClosed()) {
oldCursor.close();
}
} catch (Exception e) {
e.printStackTrace();
}
}
/**
* Creates an empty unspecified CursorLoader. You must follow this with
* calls to {#link #setUri(Uri)}, {#link #setSelection(String)}, etc
* to specify the query to perform.
*/
public SQLiteCursorLoader(Context context) {
super(context);
mObserver = new ForceLoadContentObserver();
}
/**
* Creates a fully-specified CursorLoader. See
* {#link ContentResolver#query(Uri, String[], String, String[], String)
* ContentResolver.query()} for documentation on the meaning of the
* parameters. These will be passed as-is to that call.
*/
public SQLiteCursorLoader(Context context, Uri uri, String[] projection, String selection,
String[] selectionArgs, String sortOrder) {
super(context);
mObserver = new ForceLoadContentObserver();
mUri = uri;
mProjection = projection;
mSelection = selection;
mSelectionArgs = selectionArgs;
mSortOrder = sortOrder;
}
/**
* Starts an asynchronous load of the contacts list data. When the result is ready the callbacks
* will be called on the UI thread. If a previous load has been completed and is still valid
* the result may be passed to the callbacks immediately.
* <p>
* Must be called from the UI thread
*/
#Override
protected void onStartLoading() {
if (mCursor != null) {
deliverResult(mCursor);
}
if (takeContentChanged() || mCursor == null) {
forceLoad();
}
}
/**
* Must be called from the UI thread
*/
#Override
protected void onStopLoading() {
// Attempt to cancel the current load task if possible.
cancelLoad();
}
#Override
public void onCanceled(Cursor cursor) {
if (cursor != null && !cursor.isClosed()) {
cursor.close();
}
}
#Override
protected void onReset() {
super.onReset();
// Ensure the loader is stopped
onStopLoading();
if (mCursor != null && !mCursor.isClosed()) {
mCursor.close();
}
mCursor = null;
}
public Uri getUri() {
return mUri;
}
public void setUri(Uri uri) {
mUri = uri;
}
public String[] getProjection() {
return mProjection;
}
public void setProjection(String[] projection) {
mProjection = projection;
}
public String getSelection() {
return mSelection;
}
public void setSelection(String selection) {
mSelection = selection;
}
public String[] getSelectionArgs() {
return mSelectionArgs;
}
public void setSelectionArgs(String[] selectionArgs) {
mSelectionArgs = selectionArgs;
}
public String getSortOrder() {
return mSortOrder;
}
public void setSortOrder(String sortOrder) {
mSortOrder = sortOrder;
}
#Override
public void dump(String prefix, FileDescriptor fd, PrintWriter writer, String[] args) {
super.dump(prefix, fd, writer, args);
writer.print(prefix);
writer.print("mUri=");
writer.println(mUri);
writer.print(prefix);
writer.print("mProjection=");
writer.println(Arrays.toString(mProjection));
writer.print(prefix);
writer.print("mSelection=");
writer.println(mSelection);
writer.print(prefix);
writer.print("mSelectionArgs=");
writer.println(Arrays.toString(mSelectionArgs));
writer.print(prefix);
writer.print("mSortOrder=");
writer.println(mSortOrder);
writer.print(prefix);
writer.print("mCursor=");
writer.println(mCursor);
//writer.print(prefix); writer.print("mContentChanged="); writer.println(mContentChanged);
}
private class CursorLoaderContentObserver extends ContentObserver {
public CursorLoaderContentObserver() {
super(new Handler());
}
#Override
public boolean deliverSelfNotifications() {
return true;
}
#Override
public void onChange(boolean selfChange) {
onContentChanged();
}
}
}

You should call notifyDataSetChanged just before dismissing the dialoge
teamListArrayAdapter.notifyDataSetChanged();
You should change you code something like this below
#Override
public void onClick(View view) {
int id = view.getId();
switch (id){
case R.id.button_alertDialogAddTeam_cancel:
this.dismiss();
break;
case R.id.button_alertDialogAddTeam_ok:
Team team = new Team();
team.setName(editTextTeamName.getText().toString());
team.setCode(editTextTeamCode.getText().toString());
TeamDatabase teamDatabase = new TeamDatabase(getContext());
teamDatabase.open();
if(teamDatabase.addNewTeam(team)) {
Toast.makeText(getContext(), team.getCode() + " - " +
team.getName() + " was added successfully", Toast.LENGTH_SHORT).show();
}
arrayListTeam = teamDatabase.getAllTeams();
teamListArrayAdapter.notifyDataSetChanged();
this.dismiss();
break;
}
}

Add this code in onCreateView:
teamListArrayAdapter.notifyDataSetChanged();

sqlite.SQLiteException: no such column. I checked on commas and spaces [duplicate]

This question already has answers here:
When does SQLiteOpenHelper onCreate() / onUpgrade() run?
(15 answers)
Closed 7 years ago.
I cannot find the problem in my (Android) Java code.
The problem (according the logcat) is that there is no such column as reminder_date.
This is the error:
09-19 21:27:24.440 23689-23689/com.example.sanne.reminderovapplication E/AndroidRuntime﹕ FATAL EXCEPTION: main
Process: com.example.sanne.reminderovapplication, PID: 23689
java.lang.RuntimeException: Unable to start activity ComponentInfo{com.example.sanne.reminderovapplication/com.example.sanne.reminderovapplication.MainActivity}: android.database.sqlite.SQLiteException: no such column: reminder_date (code 1): , while compiling: SELECT reminder_id AS _id , reminder_title , reminder_description , reminder_date FROM reminder
I checked for the commas and spaces.
I hope there is a solution for this problem.
This is my code of the MySQLiteHelper:
public class MySQLiteHelper extends SQLiteOpenHelper{
// Database info
private static final String DATABASE_NAME = "reminderOVApp.db";
private static final int DATABASE_VERSION = 8;
// Assignments
public static final String TABLE_REMINDER = "reminder";
public static final String COLUMN_REMINDER_ID = "reminder_id";
public static final String COLUMN_REMINDER_TITLE = "reminder_title";
public static final String COLUMN_REMINDER_DESCRIPTION = "reminder_description";
public static final String COLUMN_REMINDER_DATE = "reminder_date";
// Creating the table
private static final String DATABASE_CREATE_REMINDERS =
"CREATE TABLE " + TABLE_REMINDER +
"(" +
COLUMN_REMINDER_ID + " integer primary key autoincrement , " +
COLUMN_REMINDER_TITLE + " text not null , " +
COLUMN_REMINDER_DESCRIPTION + " text not null , " +
COLUMN_REMINDER_DATE + " text not null " +
");";
// Mandatory constructor which passes the context, database name and database version and passes it to the parent
public MySQLiteHelper(Context context) {
super(context, DATABASE_NAME, null, DATABASE_VERSION);
}
#Override
public void onCreate(SQLiteDatabase database)
{
// Execute the sql to create the table assignments
database.execSQL(DATABASE_CREATE_REMINDERS);
}
#Override
public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion)
{
// When the database gets upgraded you should handle the update to make sure there is no data loss.
// This is the default code you put in the upgrade method, to delete the table and call the oncreate again.
if(oldVersion == 8)
{
db.execSQL("DROP TABLE IF EXISTS " + TABLE_REMINDER);
onCreate(db);
}
}
And this is the code of the DataSource Class:
public class DataSource {
private SQLiteDatabase database;
private MySQLiteHelper dbHelper;
private String[] assignmentAllColumns = {MySQLiteHelper.COLUMN_REMINDER_ID, MySQLiteHelper.COLUMN_REMINDER_TITLE, MySQLiteHelper.COLUMN_REMINDER_DESCRIPTION, MySQLiteHelper.COLUMN_REMINDER_DATE};
public DataSource(Context context) {
dbHelper = new MySQLiteHelper(context);
database = dbHelper.getWritableDatabase();
dbHelper.close();
}
// Opens the database to use it
public void open() throws SQLException {
database = dbHelper.getWritableDatabase();
}
// Closes the database when you no longer need it
public void close() {
dbHelper.close();
}
//Add a reminder to the database
public long createReminder(String reminder_title, String reminder_description, String reminder_date) {
// If the database is not open yet, open it
if (!database.isOpen()) {
open();
}
ContentValues values = new ContentValues();
values.put(MySQLiteHelper.COLUMN_REMINDER_TITLE, reminder_title);
values.put(MySQLiteHelper.COLUMN_REMINDER_DESCRIPTION, reminder_description);
values.put(MySQLiteHelper.COLUMN_REMINDER_DATE, reminder_date);
// values.put(MySQLiteHelper.COLUMN_REMINDER_TIME, reminder_time);
long insertId = database.insert(MySQLiteHelper.TABLE_REMINDER, null, values);
// If the database is open, close it
if (database.isOpen()) {
close();
}
return insertId;
}
//Change data of the specific reminder
public void updateReminder(Reminder reminder) {
if (!database.isOpen()) {
open();
}
ContentValues args = new ContentValues();
args.put(MySQLiteHelper.COLUMN_REMINDER_TITLE, reminder.getTitle());
args.put(MySQLiteHelper.COLUMN_REMINDER_DESCRIPTION, reminder.getDescription());
args.put(MySQLiteHelper.COLUMN_REMINDER_DATE, reminder.getDate());
database.update(MySQLiteHelper.TABLE_REMINDER, args, MySQLiteHelper.COLUMN_REMINDER_ID + "=?", new String[] { Long.toString(reminder.getId()) });
if (database.isOpen()) {
close();
}
}
//Delete a reminder from the database
public void deleteReminder(long id) {
if (!database.isOpen()) {
open();
}
database.delete(MySQLiteHelper.TABLE_REMINDER, MySQLiteHelper.COLUMN_REMINDER_ID + " =?", new String[]{Long.toString(id)});
if (database.isOpen()) {
close();
}
}
//Delete all reminders
public void deleteReminders() {
if (!database.isOpen()) {
open();
}
database.delete(MySQLiteHelper.TABLE_REMINDER, null, null);
if (database.isOpen()) {
close();
}
}
//This way you can get the id and the reminder from the cursor.
private Reminder cursorToReminder(Cursor cursor) {
try {
Reminder reminder = new Reminder();
reminder.setId(cursor.getLong(cursor.getColumnIndexOrThrow(MySQLiteHelper.COLUMN_REMINDER_ID)));
reminder.setTitle(cursor.getString(cursor.getColumnIndexOrThrow(MySQLiteHelper.COLUMN_REMINDER_TITLE)));
reminder.setDescription(cursor.getString(cursor.getColumnIndexOrThrow(MySQLiteHelper.COLUMN_REMINDER_DESCRIPTION)));
reminder.setDate(cursor.getString(cursor.getColumnIndexOrThrow(MySQLiteHelper.COLUMN_REMINDER_DATE)));
return reminder;
}catch(CursorIndexOutOfBoundsException exception) {
exception.printStackTrace();
return null;
}
}
//Get all the reminders to populate the listView --> ArrayList
public List<Reminder> getAllReminders() {
if (!database.isOpen()) {
open();
}
List<Reminder> reminders = new ArrayList<Reminder>();
Cursor cursor = database.query(MySQLiteHelper.TABLE_REMINDER, assignmentAllColumns, null, null, null, null, null);
cursor.moveToFirst();
while (!cursor.isAfterLast()) {
Reminder assignment = cursorToReminder(cursor);
reminders.add(assignment);
cursor.moveToNext();
}
// make sure to close the cursor
cursor.close();
if (database.isOpen()) {
close();
}
return reminders;
}
//A SimpleCursorAdapter requires a Cursor to get the data from the database instead of an ArrayList.
public Cursor getAllAssignmentsCursor()
{
if (!database.isOpen()) {
open();
}
Cursor cursor = database.rawQuery(
"SELECT " +
MySQLiteHelper.COLUMN_REMINDER_ID + " AS _id , " +
MySQLiteHelper.COLUMN_REMINDER_TITLE + " , " +
MySQLiteHelper.COLUMN_REMINDER_DESCRIPTION + " , " +
MySQLiteHelper.COLUMN_REMINDER_DATE +
" FROM " + MySQLiteHelper.TABLE_REMINDER, null);
if (cursor != null) {
cursor.moveToFirst();
}
if (database.isOpen()) {
close();
}
return cursor;
}
//Get one reminder
public Reminder getReminder(long columnId) {
if (!database.isOpen()) {
open();
}
Cursor cursor = database.query(MySQLiteHelper.TABLE_REMINDER, assignmentAllColumns, MySQLiteHelper.COLUMN_REMINDER_ID + "=?", new String[] { Long.toString(columnId)}, null, null, null);
cursor.moveToFirst();
Reminder assignment = cursorToReminder(cursor);
cursor.close();
if (database.isOpen()) {
close();
}
return assignment;
}}
And my MainActivity Class:
public class AddActivity extends AppCompatActivity {
private DataSource datasource;
private EditText addReminderEditText;
private EditText descriptionEditText;
private EditText dateEditText;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_add);
datasource = new DataSource(this);
addReminderEditText = (EditText) findViewById(R.id.add_reminder_editText);
descriptionEditText = (EditText) findViewById(R.id.description_reminder_editText);
dateEditText = (EditText) findViewById(R.id.date_reminder_editText);
}
#Override
public boolean onCreateOptionsMenu(Menu menu) {
// Inflate the menu; this adds items to the action bar if it is present.
getMenuInflater().inflate(R.menu.menu_add, menu);
return true;
}
#Override
public boolean onOptionsItemSelected(MenuItem item) {
// Handle action bar item clicks here. The action bar will
// automatically handle clicks on the Home/Up button, so long
// as you specify a parent activity in AndroidManifest.xml.
int id = item.getItemId();
//noinspection SimplifiableIfStatement
if (id == R.id.add_assignment_menu_save) {
//Sending the data back to MainActivity
long reminderId = datasource.createReminder(addReminderEditText.getText().toString(), descriptionEditText.getText().toString(), dateEditText.getText().toString());
Intent resultIntent = new Intent();
resultIntent.putExtra(MainActivity.EXTRA_REMINDER_ID, reminderId);
setResult(Activity.RESULT_OK, resultIntent);
finish();
return true;
}
return super.onOptionsItemSelected(item);
}}

Well, it seems like reminder_date has been added after the first code execution.
Simply uninstall and reinstall your app.

Total price using rawQuery in android [closed]

Closed. This question needs details or clarity. It is not currently accepting answers.
Want to improve this question? Add details and clarify the problem by editing this post.
Closed 8 years ago.
Improve this question
I've been trying to get the price value from the database and try to make a grand total. I used the rawQuery but always crashed.I think theres a problem in my rawQuery..i still cant get the total after many times i've tried..
this is the code:
DBAdapter
import android.content.ContentValues;
import android.content.Context;
import android.database.Cursor;
import android.database.sqlite.SQLiteDatabase;
import android.database.sqlite.SQLiteOpenHelper;
import android.util.Log;
// ------------------------------------ DBAdapter.java ---------------------------------------------
// TO USE:
// Change the package (at top) to match your project.
// Search for "TODO", and make the appropriate changes.
public class DBAdapter {
/////////////////////////////////////////////////////////////////////
// Constants & Data
/////////////////////////////////////////////////////////////////////
// For logging:
private static final String TAG = "DBAdapter";
// DB Fields
public static final String KEY_ROWID = "_id";
public static final int COL_ROWID = 0;
/*
* CHANGE 1:
*/
// TODO: Setup your fields here:
public static final String KEY_NAME = "name";
public static final String KEY_QUANTITY = "studentnum";
public static final String KEY_PRICE = "favcolour";
// TODO: Setup your field numbers here (0 = KEY_ROWID, 1=...)
public static final int COL_NAME = 1;
public static final int COL_QUANTITY = 2;
public static final int COL_PRICE = 3;
public static final String[] ALL_KEYS = new String[] {KEY_ROWID, KEY_NAME, KEY_QUANTITY, KEY_PRICE};
// DB info: it's name, and the table we are using (just one).
public static final String DATABASE_NAME = "MyDb";
public static final String DATABASE_TABLE = "mainTable";
// Track DB version if a new version of your app changes the format.
public static final int DATABASE_VERSION = 2;
private static final String DATABASE_CREATE_SQL =
"create table " + DATABASE_TABLE
+ " (" + KEY_ROWID + " integer primary key autoincrement, "
/*
* CHANGE 2:
*/
// TODO: Place your fields here!
// + KEY_{...} + " {type} not null"
// - Key is the column name you created above.
// - {type} is one of: text, integer, real, blob
// (http://www.sqlite.org/datatype3.html)
// - "not null" means it is a required field (must be given a value).
// NOTE: All must be comma separated (end of line!) Last one must have NO comma!!
+ KEY_NAME + " text not null, "
+ KEY_QUANTITY + " integer not null, "
+ KEY_PRICE + " string not null"
// Rest of creation:
+ ");";
// Context of application who uses us.
private final Context context;
private DatabaseHelper myDBHelper;
private SQLiteDatabase db;
/////////////////////////////////////////////////////////////////////
// Public methods:
/////////////////////////////////////////////////////////////////////
public DBAdapter(Context ctx) {
this.context = ctx;
myDBHelper = new DatabaseHelper(context);
}
// Open the database connection.
public DBAdapter open() {
db = myDBHelper.getWritableDatabase();
return this;
}
// Close the database connection.
public void close() {
myDBHelper.close();
}
// Add a new set of values to the database.
public long insertRow(String name, String studentNum, String favColour) {
/*
* CHANGE 3:
*/
// TODO: Update data in the row with new fields.
// TODO: Also change the function's arguments to be what you need!
// Create row's data:
ContentValues initialValues = new ContentValues();
initialValues.put(KEY_NAME, name);
initialValues.put(KEY_QUANTITY, studentNum);
initialValues.put(KEY_PRICE, favColour);
// Insert it into the database.
return db.insert(DATABASE_TABLE, null, initialValues);
}
// Delete a row from the database, by rowId (primary key)
public boolean deleteRow(long rowId) {
String where = KEY_ROWID + "=" + rowId;
return db.delete(DATABASE_TABLE, where, null) != 0;
}
public Cursor getTotalPrice() {
Cursor c = db.rawQuery("SELECT SUM("+ KEY_PRICE +")from " + DATABASE_TABLE, null);
return c;
}
public void deleteAll() {
Cursor c = getAllRows();
long rowId = c.getColumnIndexOrThrow(KEY_ROWID);
if (c.moveToFirst()) {
do {
deleteRow(c.getLong((int) rowId));
} while (c.moveToNext());
}
c.close();
}
// Return all data in the database.
public Cursor getAllRows() {
String where = null;
Cursor c = db.query(true, DATABASE_TABLE, ALL_KEYS,
where, null, null, null, null, null);
if (c != null) {
c.moveToFirst();
}
return c;
}
// Get a specific row (by rowId)
public Cursor getRow(long rowId) {
String where = KEY_ROWID + "=" + rowId;
Cursor c = db.query(true, DATABASE_TABLE, ALL_KEYS,
where, null, null, null, null, null);
if (c != null) {
c.moveToFirst();
}
return c;
}
// Change an existing row to be equal to new data.
public boolean updateRow(long rowId, String name, int studentNum, String favColour) {
String where = KEY_ROWID + "=" + rowId;
/*
* CHANGE 4:
*/
// TODO: Update data in the row with new fields.
// TODO: Also change the function's arguments to be what you need!
// Create row's data:
ContentValues newValues = new ContentValues();
newValues.put(KEY_NAME, name);
newValues.put(KEY_QUANTITY, studentNum);
newValues.put(KEY_PRICE, favColour);
// Insert it into the database.
return db.update(DATABASE_TABLE, newValues, where, null) != 0;
}
/////////////////////////////////////////////////////////////////////
// Private Helper Classes:
/////////////////////////////////////////////////////////////////////
/**
* Private class which handles database creation and upgrading.
* Used to handle low-level database access.
*/
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_SQL);
}
#Override
public void onUpgrade(SQLiteDatabase _db, int oldVersion, int newVersion) {
Log.w(TAG, "Upgrading application's database from version " + oldVersion
+ " to " + newVersion + ", which will destroy all old data!");
// Destroy old database:
_db.execSQL("DROP TABLE IF EXISTS " + DATABASE_TABLE);
// Recreate new database:
onCreate(_db);
}
}
}
Listprice:
import android.app.AlertDialog;
import android.content.DialogInterface;
import android.content.Intent;
import android.database.Cursor;
import android.database.sqlite.SQLiteDatabase;
import android.support.v7.app.ActionBarActivity;
import android.os.Bundle;
import android.view.Menu;
import android.view.MenuItem;
import android.view.View;
import android.widget.*;
/**
* Created by User on 6/2/2015.
*/
public class Listprice extends ActionBarActivity {
DBAdapter myDb;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.listprice);
openDB();
TextView textView = (TextView) findViewById(R.id.order90);
TextView textView1 = (TextView) findViewById(R.id.quan90);
TextView textView2 = (TextView) findViewById(R.id.price90);
TextView textView3 = (TextView) findViewById(R.id.totalprice);
Bundle extras = getIntent().getExtras();
if (extras != null) {
String newText = extras.getString("firstmessage");
String newText1 = extras.getString("secondmessage");
String newText2 = extras.getString("thirdmessage");
if (newText != null) {
textView.setText(newText);
}
if (newText1 != null) {
textView1.setText(newText1);
}
if (newText2 != null) {
textView2.setText(newText2);
}
}
String num1 = textView.getText().toString().trim();
int num2 = Integer.parseInt(textView1.getText().toString());
int num3 = Integer.parseInt(textView2.getText().toString());
int num4 = num2 * num3;
registerListClickCallBack();
myDb.insertRow(num1, "Quantity = " + num2, ""+num4);
populateListViewFromDB();
Cursor sum=myDb.getTotalPrice();
textView3.setText(""+sum);
}
private void populateListViewFromDB() {
Cursor cursor = myDb.getAllRows();
//Query for the record we just added.
//Use the ID:
startManagingCursor(cursor);
String[] fromFieldNames = new String[]
{DBAdapter.KEY_NAME, DBAdapter.KEY_QUANTITY, DBAdapter.KEY_PRICE};
int[] toViewIDs = new int[]
{R.id.item_name, R.id.quantities, R.id.pricest};
SimpleCursorAdapter myCursorAdapter =
new SimpleCursorAdapter(
this,
R.layout.item_layout,
cursor,
fromFieldNames,
toViewIDs
);
// Set the adapter for the list view
ListView myList = (ListView) findViewById(R.id.listViewFromDB);
myList.setAdapter(myCursorAdapter);
}
private void openDB(){
myDb = new DBAdapter(this);
myDb.open();
}
#Override
protected void onDestroy() {
super.onDestroy();
closeDB();
}
private void closeDB() {
myDb.close();
}
private void registerListClickCallBack() {
ListView myList = (ListView) findViewById(R.id.listViewFromDB);
myList.setOnItemClickListener(new AdapterView.OnItemClickListener() {
#Override
public void onItemClick(AdapterView<?> parent, View viewClicked,
int position, long idInDB) {
updateItemForId(idInDB);
}
});
}
private void updateItemForId(final long idInDB) {
final Cursor cursor = myDb.getRow(idInDB);
if (cursor.moveToFirst()) {
AlertDialog.Builder alertDialog = new AlertDialog.Builder(Listprice.this);
// Setting Dialog Title
alertDialog.setTitle("Confirm Delete...");
// Setting Dialog Message
alertDialog.setMessage("Are you sure you want delete this?");
// Setting Positive "Yes" Button
alertDialog.setPositiveButton("YES", new DialogInterface.OnClickListener() {
public void onClick(DialogInterface dialog,int which) {
// Write your code here to invoke YES event
Toast.makeText(getApplicationContext(), "You clicked on YES", Toast.LENGTH_SHORT).show();
myDb.deleteRow(idInDB);
populateListViewFromDB();
}
});
// Setting Negative "NO" Button
alertDialog.setNegativeButton("NO", new DialogInterface.OnClickListener() {
public void onClick(DialogInterface dialog, int which) {
// Write your code here to invoke NO event
Toast.makeText(getApplicationContext(), "You clicked on NO", Toast.LENGTH_SHORT).show();
dialog.cancel();
}
});
// Showing Alert Message
alertDialog.show();
}
cursor.close();
populateListViewFromDB();
}
public void clear(View view) {
myDb.deleteAll();
populateListViewFromDB();
}
#Override
public boolean onCreateOptionsMenu(Menu menu) {
// Inflate the menu; this adds items to the action bar if it is present.
getMenuInflater().inflate(R.menu.menu_main, menu);
return true;
}
#Override
public boolean onOptionsItemSelected(MenuItem item) {
// Handle action bar item clicks here. The action bar will
// automatically handle clicks on the Home/Up button, so long
// as you specify a parent activity in AndroidManifest.xml.
int id = item.getItemId();
//noinspection SimplifiableIfStatement
if (id == R.id.action_settings) {
return true;
}
return super.onOptionsItemSelected(item);
}
public void addFood(View view) {
Intent gotofood = new Intent(this, food.class);
startActivity(gotofood);
}
public void addDrinks(View view) {
Intent gotodrinks = new Intent(this, drink.class);
startActivity(gotodrinks);
}
public void gotomainmaenu(View view) {
Intent gotomain = new Intent(this, MainActivity.class);
startActivity(gotomain);
}
}

It sounds like you want the sum of each item's price multiplied by that item's quantity. If so, this should work:
public double getTotalPrice() {
String sql = "select sum(" + KEY_QUANTITY + " * " + KEY_PRICE + ") from "
+ DATABASE_TABLE;
Cursor cursor = db.rawQuery(sql, null);
if (cursor.moveToFirst()) {
return cursor.getDouble(0);
}
return 0;
}

cursor.moveToFirst seems to be skipped

I'm new to Java and just tried to make a database. I managed to make a DB and all but when I want to read the values it seems to get an error.
This is my code for my settings activity (which asks for setting values and add them in the DB on a specific ID)
public class Settings extends Activity{
Button Save;
static Switch SwitchCalculations;
public static String bool;
public static List<Integer> list_id = new ArrayList<Integer>();
public static List<String> list_idname = new ArrayList<String>();
public static List<String> list_kind = new ArrayList<String>();
public static List<String> list_value = new ArrayList<String>();
static Integer[] arr_id;
static String[] arr_idname;
static String[] arr_kind;
static String[] arr_value;
public static final String TAG = "Settings";
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.settings);
Save = (Button) findViewById(R.id.btnSave);
SwitchCalculations = (Switch) findViewById(R.id.switchCalcOnOff);
readData();
Save.setOnClickListener(new OnClickListener() {
public void onClick(View v) {
writeData();
//Toast.makeText(this, "Data has been saved.", Toast.LENGTH_SHORT).show();
readData();
Save.setText("Opgeslagen");
}
});
}
public void writeData() {
int id = 1;
String idname = "switchCalcOnOff";
String kind = "switch";
boolean val = SwitchCalculations.isChecked();
String value = new Boolean(val).toString();
dbHelper_Settings dbh = new dbHelper_Settings(this);
SQLiteDatabase db = dbh.getWritableDatabase();
ContentValues cv = new ContentValues();
cv.put(dbh.C_ID, id);
cv.put(dbh.C_IDNAME, idname);
cv.put(dbh.C_KIND, kind);
cv.put(dbh.C_VALUE, value);
if (dbh.C_ID.isEmpty() == true) {
db.insert(dbh.TABLE, null, cv);
Log.d(TAG, "Insert: Data has been saved.");
} else if (dbh.C_ID.isEmpty() == false) {
db.update(dbh.TABLE, cv, "n_id='1'", null);
Log.d(TAG, "Update: Data has been saved.");
} else {
Log.d(TAG, "gefaald");
}
db.close();
}
public void readData() {
dbHelper_Settings dbh = new dbHelper_Settings(this);
SQLiteDatabase db = dbh.getWritableDatabase();
List<String> list_value = new ArrayList<String>();
String[] arr_value;
list_value.clear();
Cursor cursor = db.rawQuery("SELECT " + dbh.C_VALUE + " FROM " + dbh.TABLE + ";", null);
if (cursor.moveToFirst()) {
do {
list_value.add(cursor.getString(0));
} while (cursor.moveToNext());
}
if (cursor != null && !cursor.isClosed()){
cursor.close();
}
db.close();
arr_value = new String[list_value.size()];
for (int i = 0; i < list_value.size(); i++){
arr_value[i] = list_value.get(i);
}
}
}
Then I have my dbHelper activity see below:
package com.amd.nutrixilium;
import android.content.Context;
import android.database.sqlite.SQLiteDatabase;
import android.database.sqlite.SQLiteOpenHelper;
import android.util.Log;
public class dbHelper_Settings extends SQLiteOpenHelper{
private static final String TAG="dbHelper_Settings";
public static final String DB_NAME = "settings.db";
public static final int DB_VERSION = 10;
public final String TABLE = "settings";
public final String C_ID = "n_id"; // Special for id
public final String C_IDNAME = "n_idname";
public final String C_KIND = "n_kind";
public final String C_VALUE = "n_value";
Context context;
public dbHelper_Settings(Context context) {
super(context, DB_NAME, null, DB_VERSION);
this.context = context;
}
// oncreate wordt maar 1malig uitgevoerd per user voor aanmaken van database
#Override
public void onCreate(SQLiteDatabase db) {
String sql = String.format("create table %s (%s int primary key, %s TEXT, %s TEXT, %s TEXT)", TABLE, C_ID, C_IDNAME, C_KIND, C_VALUE);
Log.d(TAG, "onCreate sql: " + sql);
db.execSQL(sql);
}
#Override
public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {
db.execSQL("drop table if exists " + TABLE); // wist een oudere database versie
Log.d(TAG, "onUpgrate dropped table " + TABLE);
this.onCreate(db);
}
}
And the weird thing is I don't get any error messages here.
But I used Log.d(TAG, text) to check where the script is being skipped and that is at cursor.moveToFirst().
So can anyone help me with this problem?

Here, contrary to what you seem to expect, you actually check that a text constant is not empty:
if (dbh.C_ID.isEmpty() == true) {
It isn't : it always contains "n_id"
I think your intent was to find a record with that id and, depending on the result, either insert or update.
You should do just that: attempt a select via the helper, then insert or update as in the code above.
Edit:
Add to your helper something like this:
public boolean someRowsExist(SQLiteDatabase db) {
Cursor cursor = db.rawQuery("select EXISTS ( select 1 from " + TABLE + " )", new String[] {});
cursor.moveToFirst();
boolean exists = (cursor.getInt(0) == 1);
cursor.close();
return exists;
}
And use it to check if you have any rows in the DB:
if (dbh.someRowsExist(db)) { // instead of (dbh.C_ID.isEmpty() == true) {

Looks like you're having trouble debugging your query. Android provides a handy method DatabaseUtils.dumpCursorToString() that formats the entire Cursor into a String. You can then output the dump to LogCat and see if any rows were actually skipped.

problem in database in android

hi i am an SEO and i am in currently practicing android development of my own. i studied about database storing in android developers site and found an example code that to be in a notepad.
I tried using it in my project. In my project i have placed 2 edit boxes with a OK button, when the OK button is clicked the data in the edit box gets stored and it is shown in a new page.
the following is the code of my project's main class file,
{
b = (Button)findViewById(R.id.widget30);
et1 = (EditText)findViewById(R.id.et1);
et2 = (EditText)findViewById(R.id.et2);
Bundle extras = getIntent().getExtras();
if (extras != null) {
String title = extras.getString(NotesDbAdapter.KEY_ET1);
String body = extras.getString(NotesDbAdapter.KEY_ET2);
mRowId = extras.getLong(NotesDbAdapter.KEY_ROWID);
if (title != null) {
et1.setText(title);
}
if (body != null) {
et2.setText(body);
}
}
b.setOnClickListener(new View.OnClickListener()
{
#Override
public void onClick(View v)
{
if(et1.getText().toString().length() == 0 && et2.getText().toString().length() == 0)
{
et.setVisibility(View.VISIBLE);
alertbox();
}
else
{
main.this.finish();
Intent myIntent = new Intent(v.getContext(), T.class);
startActivityForResult(myIntent, 0);
}
}
});
}
public void alertbox()
{
et = new TextView(this);
Builder alert =new AlertDialog.Builder(main.this);
alert.setTitle("Alert");
alert.setMessage("Required all fields");
alert.setPositiveButton("Ok", new DialogInterface.OnClickListener()
{
public void onClick(DialogInterface dialog, int whichButton)
{
dialog.cancel();
}
});
AlertDialog alert1 = alert.create();
alert1.show();
}
}
the following is the code of the DataBaseAdapter
public class NotesDbAdapter {
public static final String KEY_ET1 = "a";
public static final String KEY_ET2 = "b";
public static final String KEY_ROWID = "_id";
private static final String TAG = "NotesDbAdapter";
private DatabaseHelper mDbHelper;
private SQLiteDatabase mDb;
private static final String DATABASE_CREATE =
"create table notes (_id integer primary key autoincrement, "
+ "title text not null, body text not null);";
private static final String DATABASE_NAME = "data";
private static final String DATABASE_TABLE = "notes";
private static final int DATABASE_VERSION = 2;
private final Context mCtx;
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 notes");
onCreate(db);
}
}
public NotesDbAdapter(Context ctx) {
this.mCtx = ctx;
}
public NotesDbAdapter open() throws SQLException {
mDbHelper = new DatabaseHelper(mCtx);
mDb = mDbHelper.getWritableDatabase();
return this;
}
public void close() {
mDbHelper.close();
}
public long createNote(String a, String b) {
ContentValues initialValues = new ContentValues();
initialValues.put(KEY_ET1, a);
initialValues.put(KEY_ET2, b);
return mDb.insert(DATABASE_TABLE, null, initialValues);
}
public boolean deleteNote(long rowId) {
return mDb.delete(DATABASE_TABLE, KEY_ROWID + "=" + rowId, null) > 0;
}
public Cursor fetchAllNotes() {
return mDb.query(DATABASE_TABLE, new String[] {KEY_ROWID, KEY_ET1,
KEY_ET2}, null, null, null, null, null);
}
public Cursor fetchNote(long rowId) throws SQLException {
Cursor mCursor =
mDb.query(true, DATABASE_TABLE, new String[] {KEY_ROWID,
KEY_ET1, KEY_ET2}, KEY_ROWID + "=" + rowId, null,
null, null, null, null);
if (mCursor != null) {
mCursor.moveToFirst();
}
return mCursor;
}
public boolean updateNote(long rowId, String a, String b) {
ContentValues args = new ContentValues();
args.put(KEY_ET1, a);
args.put(KEY_ET2, b);
return mDb.update(DATABASE_TABLE, args, KEY_ROWID + "=" + rowId, null) > 0;
}
}
when i run the project the new page is opening but the data's entered is not shown there.
what is to be the error. pls teach me

You are going to need to get an instance of your database adapter
NotesDbAdapter adapter = new NotesDbAdapter(this); //pass activity context as a param
then you need to use the open method of the new database object to open the database
adapter.open();
now call the store method
String str = myEditText.getText().toString();
String str1 = "random other string";
adapter.createNote(str, str1);
I notice that your createNote method takes two params. I dont know where you want to get the other data from, so I just used 'random other string'. Sub in the data you want to store as appropriate.
Finally you will need to close the database:
adapter.close();
And you have successfully stored the information. See this for help on how to use the console to view the data that you have entered into the database. (See specifically the sqlite3 portion of the page) Alternatively you could write some code to display it on the screen after retrieving it. You are going to need to read about cursors if you want to retrieve info. See here for some information on that.