Develop Reference

SQL Lite Data not being inserted (Android Studio in java)

I want to insert data from user input on the click of a button but it does not get added. In my addData function it is always returning false. I don't seem to understand why this is happening nor do I have any clue where the error is since my code isn't producing any.
Here is my Database Helper code:
private static final String TAG = "DatabaseHelper";
private static final String TABLE_NAME = "nutrition_table";
private static final String COL1 = "ID";
private static final String COL2 = "food";
private static final String COL3 = "calories";
DatabaseHelper(Context context) {
super(context, TABLE_NAME, null, 1);
}
#Override
public void onCreate(SQLiteDatabase DB) {
String createTable = "CREATE TABLE " + TABLE_NAME + " (ID INTEGER PRIMARY KEY AUTOINCREMENT, " +
COL2 + " TEXT" + COL3 + " ,TEXT)" ;
DB.execSQL(createTable);
}
#Override
public void onUpgrade(SQLiteDatabase DB, int i, int i1) {
DB.execSQL("DROP TABLE IF EXISTS " + TABLE_NAME);
onCreate(DB);
}
public boolean addData(String item) {
SQLiteDatabase db = this.getWritableDatabase();
ContentValues contentValues = new ContentValues();
contentValues.put(COL2, item);
contentValues.put(COL3, item);
Log.d(TAG, "addData: Adding " + item + "to" + TABLE_NAME);
long res = db.insert(TABLE_NAME, null, contentValues);
if (res == -1) {
return false;
} else {
return true;
}
}
public Cursor getData() {
SQLiteDatabase db = this.getWritableDatabase();
String query = "SELECT * FROM " + TABLE_NAME;
Cursor data = db.rawQuery(query, null);
return data;
}
}
Here is my addActivity code:
DatabaseHelper mDbhelper;
TextView addFood, addCals;
Button addEntry, deleteEntry;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_add);
addFood = findViewById(R.id.addFoodItemTextView);
addCals = findViewById(R.id.addCaloriesTextView);
addEntry = findViewById(R.id.addBtn);
deleteEntry = findViewById(R.id.deleteBtn);
mDbhelper = new DatabaseHelper(this);
addEntry.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View view) {
String foodEntry = addFood.getText().toString();
String calsEntry = addCals.getText().toString();
if (foodEntry.length() != 0) {
addData(foodEntry);
addFood.setText("");
} else {
toastMessage("You have to add data in the food/meal text field!");
}
if (calsEntry.length() != 0) {
addData(calsEntry);
addCals.setText("");
} else {
toastMessage("You have to add data in the calorie text field");
}
}
});
}
public void addData(String newEntry) {
boolean insertData = mDbhelper.addData(newEntry);
if (insertData) {
toastMessage("Added to entries");
} else {
toastMessage("Something went wrong");
}
}
private void toastMessage(String message) {
Toast.makeText(this, message, Toast.LENGTH_SHORT).show();
}
}
Here is the code where the data is supposed to be displayed:
private final static String TAG = "listData";
DatabaseHelper dbHelper;
private ListView displayData;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_view_entries);
displayData = findViewById(R.id.listData);
dbHelper = new DatabaseHelper(this);
populateListView();
}
private void populateListView() {
Log.d(TAG, "populateListView: Displaying data in the ListView.");
Cursor data = dbHelper.getData();
ArrayList<String> listData = new ArrayList<>();
while(data.moveToNext()) {
listData.add(data.getString(1));
listData.add(data.getString(2));
}
ListAdapter adapter = new ArrayAdapter<>(this, android.R.layout.simple_list_item_1, listData);
displayData.setAdapter(adapter);
}
}
Keep in mind that I am using an intent to view the entries (When the user clicks the button it brings him to the View entries page). I'm not sure where my code went wrong. Any help is greatly appreciated.
Thanks!

Populating listview from Database, doesn't show anything

I saw this tutorial: https://www.youtube.com/watch?v=gaOsl2TtMHs
but it seem that when i see the activity there isn't any item listview :\
What can be the problem? I put my code under below
The Main Activity.java
public class Prova2 extends Activity {
int[] imageIDs = {
R.drawable.spaghettiscoglio,
R.drawable.abbacchioascottadito,
R.drawable.agnellocacioeova,
R.drawable.agnolotti,
R.drawable.alettedipollo,
R.drawable.amaretti,
R.drawable.anatraarancia,
R.drawable.alberinatale
};
int nextImageIndex = 0;
DBAdapter myDb;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.prova2);
openDB();
populateListViewFromDB();
registerListClickCallback();
}
#Override
protected void onDestroy() {
super.onDestroy();
closeDB();
}
private void openDB() {
myDb = new DBAdapter(this);
myDb.open();
}
private void closeDB() {
myDb.close();
}
/*
* UI Button Callbacks
*/
public void onClick_AddRecord(View v) {
int imageId = imageIDs[nextImageIndex];
nextImageIndex = (nextImageIndex + 1) % imageIDs.length;
// Add it to the DB and re-draw the ListView
myDb.insertRow("Jenny" + nextImageIndex, imageId, "Green");
populateListViewFromDB();
}
public void onClick_ClearAll(View v) {
myDb.deleteAll();
populateListViewFromDB();
}
private void populateListViewFromDB() {
Cursor cursor = myDb.getAllRows();
// Allow activity to manage lifetime of the cursor.
// DEPRECATED! Runs on the UI thread, OK for small/short queries.
startManagingCursor(cursor);
// Setup mapping from cursor to view fields:
String[] fromFieldNames = new String[]
{DBAdapter.KEY_NAME, DBAdapter.KEY_STUDENTNUM, DBAdapter.KEY_FAVCOLOUR, DBAdapter.KEY_STUDENTNUM};
int[] toViewIDs = new int[]
{R.id.tvFruitPrice, R.id.ivFruit, R.id.tvFruitPrice, R.id.smalltext};
// Create adapter to may columns of the DB onto elemesnt in the UI.
SimpleCursorAdapter myCursorAdapter =
new SimpleCursorAdapter(
this, // Context
R.layout.sis, // Row layout template
cursor, // cursor (set of DB records to map)
fromFieldNames, // DB Column names
toViewIDs // View IDs to put information in
);
// Set the adapter for the list view
ListView myList = (ListView) findViewById(R.id.listViewFromDB);
myList.setAdapter(myCursorAdapter);
}
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);
displayToastForId(idInDB);
}
});
}
private void updateItemForId(long idInDB) {
Cursor cursor = myDb.getRow(idInDB);
if (cursor.moveToFirst()) {
long idDB = cursor.getLong(DBAdapter.COL_ROWID);
String name = cursor.getString(DBAdapter.COL_NAME);
int studentNum = cursor.getInt(DBAdapter.COL_STUDENTNUM);
String favColour = cursor.getString(DBAdapter.COL_FAVCOLOUR);
favColour += "!";
myDb.updateRow(idInDB, name, studentNum, favColour);
}
cursor.close();
populateListViewFromDB();
}
private void displayToastForId(long idInDB) {
Cursor cursor = myDb.getRow(idInDB);
if (cursor.moveToFirst()) {
long idDB = cursor.getLong(DBAdapter.COL_ROWID);
String name = cursor.getString(DBAdapter.COL_NAME);
int studentNum = cursor.getInt(DBAdapter.COL_STUDENTNUM);
String favColour = cursor.getString(DBAdapter.COL_FAVCOLOUR);
String message = "ID: " + idDB + "\n"
+ "Name: " + name + "\n"
+ "Std#: " + studentNum + "\n"
+ "FavColour: " + favColour;
Toast.makeText(Prova2.this, message, Toast.LENGTH_LONG).show();
}
cursor.close();
}
The DBAdaptor.java
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_STUDENTNUM = "studentnum";
public static final String KEY_FAVCOLOUR = "favcolour";
// TODO: Setup your field numbers here (0 = KEY_ROWID, 1=...)
public static final int COL_NAME = 1;
public static final int COL_STUDENTNUM = 2;
public static final int COL_FAVCOLOUR = 3;
public static final String[] ALL_KEYS = new String[] {KEY_ROWID, KEY_NAME, KEY_STUDENTNUM, KEY_FAVCOLOUR};
// 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_STUDENTNUM + " integer not null, "
+ KEY_FAVCOLOUR + " 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, int 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_STUDENTNUM, studentNum);
initialValues.put(KEY_FAVCOLOUR, 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 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_STUDENTNUM, studentNum);
newValues.put(KEY_FAVCOLOUR, 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);
}
}

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.

Listview with Cusror adapter displays nothing

In my android app, I read some data from SQLite database and tried to display it into listview. Here is my code:
ListView listContent;
SQLiteAdapterno nadapter;
public void onCreate(Bundle savedInstanceState)
{
super.onCreate(savedInstanceState);
setContentView(R.layout.ofrnumber);
listContent=(ListView)findViewById(R.id.listView1);
nadapter=new SQLiteAdapterno(this);
nadapter.openToRead();
Cursor c=nadapter.queueAll();
String[] from = new String[]{SQLiteAdapterno.KEY_ID, SQLiteAdapterno.KEY_RCODE, SQLiteAdapterno.KEY_RNAME,SQLiteAdapterno.KEY_OFNO};
int[] to = new int[]{R.id.id,R.id.text1,android.R.id.text2,android.R.id.text2};
SimpleCursorAdapter cursorAdapter =new SimpleCursorAdapter(this, R.layout.row,c, from, to);
listContent.setAdapter(cursorAdapter);
}
SQLiteAdapterno:
public class SQLiteAdapterno {
public static final String MYDATABASE_NAME2 = "MY_DATABASEOFRN";
public static final String MYDATABASE_TABLE2 = "MY_OFFERNO";
public static final int MYDATABASE_VERSION = 1;
public static final String KEY_RCODE = "rcode";
public static final String KEY_OFNO = "ofno";
public static final String KEY_RNAME = "rname";
public static final String KEY_ID = "_id";
private static final String SCRIPT_CREATE_DATABASE1 =
"create table " + MYDATABASE_TABLE2 + " ("
+ KEY_ID +" integer primary key autoincrement, "
+ KEY_RCODE + " text, "
+ KEY_RNAME + " text, "
+ KEY_OFNO + " text);";
private SQLiteHelper sqLiteHelper;
private SQLiteDatabase sqLiteDatabase;
private Context context;
public SQLiteAdapterno(Context c)
{
context=c;
}
public SQLiteAdapterno openToRead() throws android.database.SQLException {
sqLiteHelper = new SQLiteHelper(context, MYDATABASE_NAME2, null, MYDATABASE_VERSION);
sqLiteDatabase = sqLiteHelper.getReadableDatabase();
return this;
}
public SQLiteAdapterno openToWrite() throws android.database.SQLException {
sqLiteHelper = new SQLiteHelper(context, MYDATABASE_NAME2, null, MYDATABASE_VERSION);
sqLiteDatabase = sqLiteHelper.getWritableDatabase();
return this;
}
public void close(){
sqLiteHelper.close();
}
public long insert(String rcode, String rname, String ofno){
ContentValues contentValues = new ContentValues();
contentValues.put(KEY_RCODE, rcode);
contentValues.put(KEY_RNAME, rname);
contentValues.put(KEY_OFNO, ofno);
return sqLiteDatabase.insert(MYDATABASE_TABLE2, null, contentValues);
}
public Cursor queueAll(){
String[] columns = new String[]{KEY_ID, KEY_RCODE, KEY_RNAME, KEY_OFNO};
Cursor cursor = sqLiteDatabase.query(MYDATABASE_TABLE2, columns,
null, null, null, null, null);
return cursor;
}
public int deleteAll(){
return sqLiteDatabase.delete(MYDATABASE_TABLE2, null, null);
}
I didn't found the result, It doesn't show any items in Listview. Can someone say what is the mistake in this code and how to solve it?

Code seems good. Most likely your Cursor is empty. Try to add simple condition:
Cursor c = nadapter.queueAll();
if (c != null && c.getCount() > 0) {
// set Adapter
}
else {
Toast.makeText(this, "Cursor is empty", Toast.LENGTH_SHORT).show();
}
If Toast will be shown, your getAll() method returns no data.
public Cursor queueAll(){
String[] columns = new String[] {KEY_ID, KEY_RCODE, KEY_RNAME, KEY_OFNO};
Cursor cursor = sqLiteDatabase.query(MYDATABASE_TABLE2, columns,
null, null, null, null, null);
return cursor;
}
Here is problem.

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.