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Using integer value to get SQLite database table row data of row index in order to display said data in textviews in new activity

I am trying to display my FLIGHTS table row data depending on the index in a activity using textviews. How do I get the index of the table row and display the table rows columns in textviews in an activity.
Here is my activity where I am trying to display the data in textviews:
package com.example.shashank.fffffffffffffffffffffffffff;
import androidx.appcompat.app.AppCompatActivity;
import android.content.Intent;
import android.os.Bundle;
import android.widget.TextView;
import android.widget.Toast;
public class BookingActivity extends AppCompatActivity {
TextView textView;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_booking);
textView = findViewById(R.id.textView);
Intent mIntent = getIntent();
int intValue = mIntent.getIntExtra("intVariableName", 0);
textView.setText(Integer.toString(intValue));
}
}
the intValue variable I am getting from another activity which represents the position being clicked on a listview.
I am then trying to use that variable to display the row index of the FLIGHTS table into textviews.
Here is my DBHelper class:
package com.example.shashank.fffffffffffffffffffffffffff;
import android.content.ContentValues;
import android.content.Context;
import android.database.Cursor;
import android.database.sqlite.SQLiteDatabase;
import android.database.sqlite.SQLiteOpenHelper;
import androidx.annotation.Nullable;
import java.util.ArrayList;
import java.util.List;
public class DBHelper extends SQLiteOpenHelper {
public static final String DBNAME = "Login.db";
public static final String FLIGHTS = "FLIGHTS";
public static final String COLUMN_ID = "ID";
public static final String COLUMN_DESTINATION = "DESTINATION";
public static final String COLUMN_PRICE = "PRICE";
public static final String COLUMN_DEPARTURE_TIME = "DEPARTURE_TIME";
public static final String COLUMN_ARRIVAL_TIME = "ARRIVAL_TIME";
public static final String COLUMN_DURATION = "DURATION";
public static final String COLUMN_AVAILABLE_SEATS = "AVAILABLE_SEATS";
public DBHelper(Context context) {
super(context, "Login.db", null, 1);
}
#Override
public void onCreate(SQLiteDatabase MyDB) {
String createTable1 = "create Table users(username TEXT primary key, password TEXT)";
MyDB.execSQL(createTable1);
MyDB.execSQL("CREATE TABLE " + FLIGHTS + "(" + COLUMN_ID + " INTEGER PRIMARY KEY AUTOINCREMENT, " + COLUMN_DESTINATION + " TEXT, " + COLUMN_PRICE + " REAL, " + COLUMN_DEPARTURE_TIME + " TEXT, " + COLUMN_ARRIVAL_TIME + " TEXT, " + COLUMN_DURATION + " TEXT, " + COLUMN_AVAILABLE_SEATS + " INTEGER )");
ContentValues insertValues = new ContentValues();
insertValues.put(COLUMN_DESTINATION, "Cape Town");
insertValues.put(COLUMN_PRICE, 500);
insertValues.put(COLUMN_DEPARTURE_TIME, "1200");
insertValues.put(COLUMN_ARRIVAL_TIME, "1400");
insertValues.put(COLUMN_DURATION, "2");
insertValues.put(COLUMN_AVAILABLE_SEATS, 10);
MyDB.insert(FLIGHTS, null, insertValues);
ContentValues insertValues2 = new ContentValues();
insertValues2.put(COLUMN_DESTINATION, "Johannesburg");
insertValues2.put(COLUMN_PRICE, 1000);
insertValues2.put(COLUMN_DEPARTURE_TIME, "1400");
insertValues2.put(COLUMN_ARRIVAL_TIME, "1600");
insertValues2.put(COLUMN_DURATION, "2");
insertValues2.put(COLUMN_AVAILABLE_SEATS, 22);
MyDB.insert(FLIGHTS, null, insertValues2);
}
#Override
public void onUpgrade(SQLiteDatabase MyDB, int i, int i1) {
MyDB.execSQL("drop Table if exists users");
MyDB.execSQL("drop Table if exists " + FLIGHTS);
onCreate(MyDB);
}
public Boolean insertData(String username, String password){
SQLiteDatabase MyDB = this.getWritableDatabase();
ContentValues contentValues= new ContentValues();
contentValues.put("username", username);
contentValues.put("password", password);
long result = MyDB.insert("users", null, contentValues);
if(result==-1) return false;
else
return true;
}
public Boolean checkusername(String username) {
SQLiteDatabase MyDB = this.getWritableDatabase();
Cursor cursor = MyDB.rawQuery("Select * from users where username = ?", new String[]{username});
if (cursor.getCount() > 0)
return true;
else
return false;
}
public Boolean checkusernamepassword(String username, String password){
SQLiteDatabase MyDB = this.getWritableDatabase();
Cursor cursor = MyDB.rawQuery("Select * from users where username = ? and password = ?", new String[] {username,password});
if(cursor.getCount()>0)
return true;
else
return false;
}
public List<FlightsModel> getEveryone(){
List<FlightsModel> returnList = new ArrayList<>();
String queryString = "SELECT * FROM " + FLIGHTS;
SQLiteDatabase db = this.getReadableDatabase();
Cursor cursor = db.rawQuery(queryString, null);
if(cursor.moveToFirst()){
do {
int id = cursor.getInt(0);
String destination = cursor.getString(1);
double price = cursor.getDouble(2);
String departure = cursor.getString(3);
String arrival = cursor.getString(4);
String duration = cursor.getString(5);
int space = cursor.getInt(6);
FlightsModel newFlight = new FlightsModel(id, destination, price, departure, arrival, duration, space);
returnList.add(newFlight);
}while (cursor.moveToNext());
}
else{
}
cursor.close();
db.close();
return returnList;
}
}

add the following method to the DBHelper class
:-
#SuppressLint("Range") // suppress Bug/issue with getColumnIndex
public FlightsModel getFlightById(int id) {
FlightsModel rv;
SQLiteDatabase db = this.getWritableDatabase();
// Uses the query convenience method rather than raw query
Cursor csr = db.query(FLIGHTS,null,COLUMN_ID+"=?",new String[]{String.valueOf(id)},null,null,null);
if (csr.moveToFirst()) {
rv = new FlightsModel(
csr.getInt(csr.getColumnIndex(COLUMN_ID)),
csr.getString(csr.getColumnIndex(COLUMN_DESTINATION)),
csr.getDouble(csr.getColumnIndex(COLUMN_PRICE)),
csr.getString(csr.getColumnIndex(COLUMN_DEPARTURE_TIME)),
csr.getString(csr.getColumnIndex(COLUMN_ARRIVAL_TIME)),
csr.getString(csr.getColumnIndex(COLUMN_DURATION)),
csr.getInt(csr.getColumnIndex(COLUMN_AVAILABLE_SEATS))
);
} else {
rv = new FlightsModel();
}
csr.close();
// No need to close the database (inefficient to keep opening and clsoing db)
return rv;
}
note that getWritableDatabase has been used, it doesn't really matter which is used as getReadableDatabase will, unless the database can only be read, get a writeable database. i.e. getReadableDatabase will not protect against writes.
it is better to use getColumnIndex than hard code column indexes. Thus irrespective of the position of the column the column will be found, thus reducing potential maintenance issues.
Change the BookingActivity to retrieve the respective FlightsModel
:-
public class BookingActivity extends AppCompatActivity {
TextView textView;
DBHelper dbHelper; //<<<<< ADDED
FlightsModel flightsModel; //<<<<< ADDED
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_booking);
dbHelper = new DBHelper(this); //<<<<< ADDED
textView = findViewById(R.id.textView);
Intent mIntent = getIntent();
int intValue = mIntent.getIntExtra("intVariableName", 0);
flightsModel = dbHelper.getFlightById(intValue); //<<<<< get the flightModel from the database
if (flightsModel.id > 1) {
// set the appropriate textviews
} else {
// do something here to indicate no FlightsModel found in database
}
textView.setText(Integer.toString(intValue));
}
}

Android app stalls when implementing SQLite database

At first the app would just crash when I started it with an emulator, Not sure what I changed to get it to run but now it will run the onCreate method however, when I implement the addButtonClicked method the app just stalls and the Android Monitor displays "Suspending all threads" every few seconds and I'm not sure where to even begin debugging. Any pointers in the right direction would be greatly appreciated as I'm fairly new to Android development.
MainActivity.java
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.view.View;
import android.widget.EditText;
import android.widget.TextView;
public class MainActivity extends AppCompatActivity {
EditText testInput;
TextView testText;
MyDBHandler dbHandler;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
testInput = (EditText) findViewById(R.id.testInput);
testText = (TextView) findViewById(R.id.testText);
dbHandler = new MyDBHandler(this, null, null, 1);
printDatabase();
}
//Add product to database
public void addButtonClicked(View view){
Products product = new Products((testInput.getText().toString()));
dbHandler.addProduct(product);
printDatabase();
}
// Delete Items
public void deleteButtonClicked(View view){
String inputText = testText.getText().toString();
dbHandler.deleteProduct(inputText);
printDatabase();
}
public void printDatabase(){
String dbString = dbHandler.databaseToString();
testText.setText(dbString);
testInput.setText("");
}
}
Products.java
public class Products {
private int _id;
private String _productname;
public Products(){
}
public Products(String productname) {
this._productname = productname;
}
public void set_id(int _id) {
this._id = _id;
}
public void set_productname(String _productname) {
this._productname = _productname;
}
public int get_id() {
return _id;
}
public String get_productname() {
return _productname;
}
}
MyDBHandler.java
import android.database.sqlite.SQLiteDatabase;
import android.database.sqlite.SQLiteOpenHelper;
import android.database.Cursor;
import android.content.Context;
import android.content.ContentValues;
public class MyDBHandler extends SQLiteOpenHelper {
private static final int DATABASE_VERSION = 15;
private static final String DATABASE_NAME = "products.db";
public static final String TABLE_PRODUCTS = "products";
public static final String COLUMN_ID = "_id";
public static final String COLUMN_PRODUCTNAME = "productname";
public MyDBHandler(Context context, String name, SQLiteDatabase.CursorFactory factory, int version) {
super(context, DATABASE_NAME, factory, DATABASE_VERSION);
}
#Override
public void onCreate(SQLiteDatabase db) {
String query = "CREATE TABLE " + TABLE_PRODUCTS +"(" +
COLUMN_ID + " INTEGER PRIMARY KEY AUTOINCREMENT ," +
COLUMN_PRODUCTNAME +" TEXT " +
");";
db.execSQL(query);
}
#Override
public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {
db.execSQL("DROP TABLE IF EXISTS " + TABLE_PRODUCTS);
onCreate(db);
}
//Add new row to the database
public void addProduct(Products product){
ContentValues values = new ContentValues();
values.put(COLUMN_PRODUCTNAME, product.get_productname());
SQLiteDatabase db = getWritableDatabase();
db.insert(TABLE_PRODUCTS, null, values);
db.close();
}
//Delete product from database
public void deleteProduct(String productName){
SQLiteDatabase db = getWritableDatabase();
db.execSQL("DELETE FROM " + TABLE_PRODUCTS + " WHERE " + COLUMN_PRODUCTNAME + "=\"" + productName + "\";" );
}
//Print of DB as sting
public String databaseToString(){
String dbString = "";
SQLiteDatabase db = getWritableDatabase();
String query = "SELECT * FROM " + TABLE_PRODUCTS + " WHERE 1";
//Cursor point to a location in your results
Cursor c = db.rawQuery(query, null);
//Move to the first row in your results
c.moveToFirst();
while (!c.isAfterLast()){
if(c.getString(c.getColumnIndex("productname"))!= null){
dbString += c.getString(c.getColumnIndex("productname"));
dbString += "\n";
}
}
db.close();
return dbString;
}
}

for your databaseToString method you are performing a retrieve operation. You should be doing a read operation in a thread other than UI thread. Try fetching in AsyncTask. It should work. Implementation for your databaseToString should be handled by AsyncTask.
Happy Coding..

ListView duplicates items everytime I restart the activity

I feel like this is a really simple fix but I am new the android and sqlite in general. I have a array that takes data from a database and then shows them in a list. However every time I restart the app the list adds the items once again into the list. How can I make it not do this?
package com.example.assignmenttracker;
import java.util.ArrayList;
import java.util.List;
import android.content.Intent;
import android.util.Log;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.AdapterView;
import android.widget.AdapterView.OnItemClickListener;
import android.widget.ListView;
import com.example.assignmenttracker.MySQLiteHelper;
import android.os.Bundle;
import android.widget.ArrayAdapter;
import android.widget.Button;
import android.app.Activity;
public class MainActivity extends Activity {
private ListView ListView;
private Button addbutton;
public final static String ID_EXTRA="com.example.assignmenttracker._ID";
public static ArrayList<String> ArrayofName = new ArrayList<String>();
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
this.addbutton = (Button)this.findViewById(R.id.button1);
this.addbutton.setOnClickListener(new OnClickListener() {
#Override
public void onClick(View v) {
Intent intent=new Intent(MainActivity.this, AddAssign.class);
startActivity(intent);
}
});
}
private void populateListView() {
MySQLiteHelper db = new MySQLiteHelper(this);
List<tasklist> contacts = db.getSometasklist();
for (tasklist cn : contacts) {
Log.d("Reading: ", "Reading all contacts..");
String log = "Id: "+cn.getID()+" ,Task: " + cn.getTask() + " ,Date: " + cn.getDate() + " ,Status: " + cn.getStatus();
Log.d("Name: ", log);
}
ListView = (ListView) findViewById(R.id.listView1);
ArrayAdapter<String> adapter = new ArrayAdapter<String>(this,
android.R.layout.simple_list_item_1, ArrayofName);
ListView.setAdapter(adapter);
ListView.setOnItemClickListener(new OnItemClickListener() {
public void onItemClick(AdapterView<?> parent, View v,
int position, long id) {
Intent i = new Intent(MainActivity.this, ViewAssign.class);
i.putExtra(ID_EXTRA, String.valueOf(id));
startActivity(i);}
});
}
#Override
public void onResume() {
super.onResume();
populateListView();
}
}
here is the code of mysqlitehelper
package com.example.assignmenttracker;
import java.util.ArrayList;
import java.util.List;
import android.database.Cursor;
import android.database.sqlite.SQLiteOpenHelper;
import android.database.sqlite.SQLiteDatabase;
import android.content.ContentValues;
import android.content.Context;
public class MySQLiteHelper extends SQLiteOpenHelper {
// Contacts Table Columns names
private static final String TABLE_CONTACTS = "tasklist1";
private static final String KEY_ID = "id";
private static final String KEY_TASK = "task";
private static final String KEY_DESC = "desc";
private static final String KEY_MOD = "module";
private static final String KEY_DATE = "date";
private static final String KEY_TYPE = "type";
private static final String KEY_STATUS = "status";
private static final int DATABASE_VERSION = 3;
private static final String DATABASE_NAME = "tasklist1";
public MySQLiteHelper(Context context) {
super(context, DATABASE_NAME, null, DATABASE_VERSION);
}
public void onCreate(SQLiteDatabase db) {
String CREATE_TASKLIST_TABLE = "CREATE TABLE tasklist1 ( " +
"id INTEGER PRIMARY KEY AUTOINCREMENT, " +
"task TEXT, "+
"desc TEXT, "+
"module TEXT, "+
"date TEXT, "+
"type TEXT, "+
"status INTEGER )";
db.execSQL(CREATE_TASKLIST_TABLE);
}
#Override
public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {
// Drop older task list table if existed
db.execSQL("DROP TABLE IF EXISTS " + TABLE_CONTACTS);
// create fresh task list table
this.onCreate(db);
}
public void insertTask(tasklist tasklist){
// 1. get reference to writable DB
SQLiteDatabase db = this.getWritableDatabase();
ContentValues values = new ContentValues();
values.put(KEY_TASK, tasklist.getTask());
values.put(KEY_DESC, tasklist.getDesc());
values.put(KEY_MOD, tasklist.getModule());
values.put(KEY_DATE, tasklist.getDate());
values.put(KEY_TYPE, tasklist.getType());
values.put(KEY_STATUS, tasklist.getStatus());
// Inserting Row
db.insert(TABLE_CONTACTS, null, values);
db.close(); // Closing database connection
}
public List<tasklist> getAlltasklist(int passedid) {
List<tasklist> tasklistList = new ArrayList<tasklist>();
// Select All Query
String selectQuery = "SELECT * FROM " + TABLE_CONTACTS +
" where id = " + passedid;
SQLiteDatabase db = this.getWritableDatabase();
Cursor cursor = db.rawQuery(selectQuery, null);
// looping through all rows and adding to list
if (cursor.moveToFirst()) {
do {
tasklist contact = new tasklist();
contact.setTask(cursor.getString(1));
contact.setDesc(cursor.getString(2));
contact.setModule(cursor.getString(3));
contact.setDate(cursor.getString(4));
contact.setType(cursor.getString(5));
contact.setStatus(cursor.getInt(6));
String name = cursor.getString(1);
String desc =cursor.getString(2);
String module =cursor.getString(3);
String date = cursor.getString(4);
String type = cursor.getString(5);
int status = cursor.getInt(6);
ViewAssign.task= name;
ViewAssign.desc=desc;
ViewAssign.module=module;
ViewAssign.date=date;
ViewAssign.type=type;
ViewAssign.status=status;
// Adding contact to list
tasklistList.add(contact);
db.close();
} while (cursor.moveToNext());
}
return tasklistList;
}
public List<tasklist> getSometasklist() {
List<tasklist> tasklistList = new ArrayList<tasklist>();
// Select All Query
String selectQuery = "SELECT * FROM " + TABLE_CONTACTS;
SQLiteDatabase db = this.getWritableDatabase();
Cursor cursor = db.rawQuery(selectQuery, null);
// looping through all rows and adding to list
if (cursor.moveToFirst()) {
do {
tasklist contact = new tasklist();
contact.setTask(cursor.getString(1));
contact.setDate(cursor.getString(4));
String name = cursor.getString(1) +"\n"+ cursor.getString(4);
MainActivity.ArrayofName.add(name);
// Adding contact to list
tasklistList.add(contact);
db.close();
} while (cursor.moveToNext());
}
return tasklistList;
}
public void deleteTask(long row) {
// Deletes a row given its rowId, but I want to be able to pass
// in the name of the KEY_NAME and have it delete that row.
SQLiteDatabase db = this.getWritableDatabase();
db.delete(TABLE_CONTACTS, KEY_ID + "=" + row, null);
db.close();
}
}

I suspect the culprint is this:
public static ArrayList<String> ArrayofName = new ArrayList<String>();
It is a static variable, meaning that in some circumstances, it will STILL have the objects you added on app first run when you run it second time.
Possible solutions:
remove "static" keyword, or
clear ArrayOfName before populating it, eg. ArrayOfName.clear()

I know I am late but maybe it will help someone else.
You need to split ArrayList into two parts
Place the following code in MainActivity
public static ArrayList<String> ArrayofName;
And place the following in onCreate() OR onResume() method
ArrayofName = new ArrayList<String>();

ListView doesn't show anything in Android app

Ok so here is the whole code
This is MainActivity.java
package com.gobtron.database_test;
import android.database.Cursor;
import android.database.DatabaseUtils;
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.ListView;
import android.widget.SimpleCursorAdapter;
public class MainActivity extends ActionBarActivity {
DBAdapter myDb;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
openDB();
populateListView();
}
#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;
}
private void openDB() {
myDb = new DBAdapter(this);
myDb.open();
}
public void onClick_ViewData (View v){
openDB();
populateListView();
}
#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);
}
private void populateListView() {
Cursor cursor = myDb.getAllRows();
// DatabaseUtils.dumpCursor(cursor);
String[] fromFieldNames = new String[] {DBAdapter.KEY_ROWID, DBAdapter.KEY_NOM};
int[] toViewIDs = new int[] {R.id.textView2, R.id.textView3};
SimpleCursorAdapter myCursorAdapter;
myCursorAdapter = new SimpleCursorAdapter(getBaseContext(), R.layout.item_layout, cursor, fromFieldNames, toViewIDs, cursor.getCount());
ListView myList = (ListView) findViewById(R.id.listView);
myList.setAdapter(myCursorAdapter);
}
}
And this is the DPAdapter class code:
package com.gobtron.database_test;
import android.content.ContentValues;
import android.content.Context;
import android.database.Cursor;
import android.database.DatabaseUtils;
import android.database.sqlite.SQLiteDatabase;
import android.database.sqlite.SQLiteOpenHelper;
import android.util.Log;
public class DBAdapter {
private static final String TAG = "DBAdapter"; //used for logging database version changes
// Field Names:
public static final String KEY_ROWID = "_id";
public static final String KEY_MORPH = "'morph'";
public static final String KEY_LONGFRONDE = "'long_fronde'";
public static final String KEY_FORMELIMBE = "'forme_limbe'";
public static final String KEY_DISPOSFRONDE = "'dispos_fronde'";
public static final String KEY_DESC = "'description'";
public static final String KEY_DESCHOIX = "'desc_choix'";
public static final String KEY_DESCHOIX2 = "'desc_choix2'";
public static final String KEY_NOM = "'nom'";
public static final String[] ALL_KEYS ={KEY_ROWID, KEY_MORPH, KEY_LONGFRONDE, KEY_FORMELIMBE, KEY_DISPOSFRONDE, KEY_DESC, KEY_DESCHOIX, KEY_DESCHOIX2, KEY_NOM};
public static final String[] ALL_KEYS2 = {"_id", "'long_fronde'"};
// Column Numbers for each Field Name:
public static final int COL_ROWID = 0;
public static final int COL_MORPH = 1;
public static final int COL_LONGFRONDE = 2;
public static final int COL_FORMELIMBE = 3;
public static final int COL_DISPOSFRONDE = 4;
public static final int COL_DESC = 5;
public static final int COL_DESCHOIX = 6;
public static final int COL_DESCHOIX2 = 7;
public static final int COL_NOM = 8;
// DataBase info:
public static final String DATABASE_NAME = "fougeres_db";
public static final String DATABASE_TABLE = "mono_dimo";
public static final int DATABASE_VERSION = 3; // The version number must be incremented each time a change to DB structure occurs.
//SQL statement to create database
private static final String DATABASE_CREATE_SQL =
"CREATE TABLE " + DATABASE_TABLE
+ " (" + KEY_ROWID + " INTEGER PRIMARY KEY AUTOINCREMENT, "
+ KEY_NOM + " TEXT NOT NULL, "
+ KEY_DESC + " TEXT"
+ ");";
private final Context context;
private DatabaseHelper myDBHelper;
private SQLiteDatabase db;
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 be inserted into the database.
public long insertRow(String task, String date) {
ContentValues initialValues = new ContentValues();
initialValues.put(KEY_NOM, task);
initialValues.put(KEY_MORPH, date);
// Insert the data 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(DATABASE_TABLE, ALL_KEYS, where, null, null, null, null);
DatabaseUtils.dumpCursor(c);
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 task, String date) {
String where = KEY_ROWID + "=" + rowId;
ContentValues newValues = new ContentValues();
newValues.put(KEY_NOM, task);
newValues.put(KEY_MORPH, date);
// Insert it into the database.
return db.update(DATABASE_TABLE, newValues, where, null) != 0;
}
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);
}
}
}
I don't get why my cursor is empty... I think it opens the database correctly, and the table too.
Well... I'm new to java so it is probably something stupid i'm missing.

You are trying to insert a value with key KEY_MORTH, however there is no field with this Key in your table
this:
"CREATE TABLE " + DATABASE_TABLE
+ " (" + KEY_ROWID + " INTEGER PRIMARY KEY , "
+ KEY_NOM + " TEXT NOT NULL, "
+ KEY_DESC + " TEXT"
+ ");";
needs to be
"CREATE TABLE " + DATABASE_TABLE
+ " (" + KEY_ROWID + " INTEGER PRIMARY KEY AUTOINCREMENT, "
+ KEY_NOM + " TEXT NOT NULL, "
+ KEY_DESC + " TEXT, "
+ KEY_MORTH + " TEXT "
+ ");";
You will need to update your db version or clear your data for this to take effect

Ok, turns out that my database was simply put in the wrong place. I needed to open the Android Device Monitor, then go the File Explorer, then put my existing database to /data/data/my package name/databases/

Updating specific column using a spinner widget

I am trying to update current credits column of the only row in the database using a drop down spinner which gets values from an arraylist. Very unsure about how to go about doing this operation. Thank you for any help in advance.
My database code:
package com.example.parkangel;
import android.content.Context;
import android.database.Cursor;
import android.database.SQLException;
import android.database.sqlite.SQLiteDatabase;
import android.database.sqlite.SQLiteOpenHelper;
public class UDbHelper extends SQLiteOpenHelper
{
public static final String KEY_ROWID = "_id";
public static final String KEY_PFNAME = "payeeFname";
public static final String KEY_PSNAME = "payeeSname";
public static final String KEY_CARD = "card";
public static final String KEY_CREDITS = "credits";
private static final String DATABASE_NAME = "UserData.db";
private static final String DATABASE_TABLE = "UserTable";
private static final int DATABASE_VERSION = 1;
//private UDbHelper dbHelper;
//private final Context ourContext;
private static UDbHelper instance;
private SQLiteDatabase ourDatabase;
public UDbHelper(Context context)
{
super(context, DATABASE_NAME, null, DATABASE_VERSION);
}
public static UDbHelper getInstance(Context context)
{
if (instance == null)
{
instance = new UDbHelper(context);
}
return instance;
}
#Override
public void onCreate(SQLiteDatabase db)
{
// TODO Auto-generated method stub
db.execSQL("CREATE TABLE " + DATABASE_TABLE + " (" +
KEY_ROWID + " INTEGER PRIMARY KEY AUTOINCREMENT, " +
KEY_PFNAME + " TEXT NOT NULL, " + KEY_PSNAME + "
TEXT NOT NULL, " +
KEY_CARD + " TEXT NOT NULL, " + KEY_CREDITS + " TEXT
NOT NULL);");
}
#Override
public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion)
{
// TODO Auto-generated method stub
db.execSQL("DROP TABLE IF EXISTS " + DATABASE_TABLE);
onCreate(db);
}
public synchronized UDbHelper open() throws SQLException
{
System.out.println ("running open");
if(ourDatabase == null || !ourDatabase.isOpen())
ourDatabase = getWritableDatabase();
return this;
}
public String getData()
{
// TODO Auto-generated method stub
String[] columns = new String[] {KEY_ROWID, KEY_PFNAME, KEY_PSNAME,
KEY_CARD, KEY_CREDITS};
Cursor c = ourDatabase.query(DATABASE_TABLE, columns, null, null,
null, null, null);
String result = " ";
int iRow = c.getColumnIndexOrThrow(KEY_ROWID);
int iPFname = c.getColumnIndexOrThrow(KEY_PFNAME);
int iPSname = c.getColumnIndexOrThrow(KEY_PSNAME);
int iCard = c.getColumnIndexOrThrow(KEY_CARD);
int iCredits = c.getColumnIndexOrThrow(KEY_CREDITS);
for(c.moveToFirst(); !c.isAfterLast(); c.moveToNext()){
result = result + c.getString(iRow) + " " +
c.getString(iPFname) + " " +
c.getString(iPSname)
+ " " + c.getString(iCard) + " " +
c.getString(iCredits) + "\n";
}
return result;
}
}
My main activity code I will be doing the operation through:
package com.example.parkangel;
import android.app.Activity;
import android.content.Intent;
import android.os.Bundle;
import android.view.View;
import android.widget.ArrayAdapter;
import android.widget.Button;
import android.widget.Spinner;
import android.widget.TextView;
public class Balance extends Activity{
Button add;
TextView display;
Spinner spinner3;
String[] money = {"Select amount", "£1", "£2", "£5", "£10"};
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.balance_layout);
TextView tv = (TextView) findViewById(R.id.firstn);
UDbHelper db = new UDbHelper(this);
db.open();
String data = db.getData();
db.close();
tv.setText(data);
ArrayAdapter<String> adapter3 = new ArrayAdapter<String>(Balance.this,
android.R.layout.simple_spinner_item, money);
spinner3 = (Spinner) findViewById (R.id.moneytoadd);
spinner3.setAdapter(adapter3);
add = (Button) findViewById(R.id.topup);
}
public void onClick(View arg0)
{
}
public void updateActivity(View view){
Intent book = new Intent(Balance.this, BookTicket.class);
startActivity(book);
}
public void addBalance(View view){
Intent addB = new Intent(Balance.this, Balance.class);
startActivity(addB);
}
public void doUpdate(View view){
Intent upd = new Intent(Balance.this, UpdateTicket.class);
startActivity(upd);
}
}

Your question is fairly compound, getting selected field from spinner, updating database... I'm not going to provide a complete answer, but this should get you started:
This is how you would get the selected field from the spinner, which you can then use to update your database. One word of warning, I believe setOnItemSelectedListener is called when it is initially set, so you may need to ignore the first call.
Spinner spinner;
spinner.setOnItemSelectedListener( new AdapterView.OnItemSelectedListener() {
#Override
public void onItemSelected(AdapterView<?> arg0, View view, int arg2,
long arg3) {
if(! (view instanceof TextView)){
// view is probably a textview, but record type if not.
System.out.println("incorrect view type " + view.getClass().getSimpleName());
return;
}
EditText et = (EditText) view;
String fieldName = et.getText().toString().trim();
//Now we got selected name, send name
//to a function that updates our database.
}
#Override
public void onNothingSelected(AdapterView<?> arg0) {
// TODO Auto-generated method stub
}
});

I didn't find the problem but I can tell you that your code is VERY INEFFICIENT. You are using String to build your result in the getData method. Each time you try to append the new data (Row) to the old one you are creating a new string to hold the new data. If you are retrieving 1000 row from the database, this means that you are creating 1000 string to build the final one. I recommend using StringBuilder instead as following:
StringBuilder strBuilder= new StringBuilder();
for(c.moveToFirst(); !c.isAfterLast(); c.moveToNext()){
strBuilder.append( c.getString(iRow) + " " +
c.getString(iPFname) + " " +
c.getString(iPSname)
+ " " + c.getString(iCard) + " " +
c.getString(iCredits) + "\n");
}
return str= strBuilder.toString();
Here is an example of how to insert into your DB:
SQLiteDatabase db = this.getWritableDatabase();
ContentValues values = new ContentValues();
values.put(KEY_PFNAME , editText1.getText().toString());
values.put(KEY_PSNAME , stringArrayList.get(position));
values.put(KEY_CARD , "12345677");
values.put(KEY_CREDITS , "55");
// Inserting Row
db.insert(DATABASE_TABLE, null, values);
db.close(); // Closing database connection