Insert and retrieval from database in android (Stucked in infinite loop) - android

The problem is i inserted only two rows but on execution it enters into infinite loop and repeatedily showing the same data..Any kind of help would be appreciated
Here is my code.
This is my databse class (i.e DbAdapter)
public Cursor getAllRows() {
String[]columns = new String[]{ KEY_MODEL,KEY_BRAND, KEY_PRICE};
Cursor c = db.query(TABLE_LAPTOPS, columns, null, null, null, null, null);
if (c != null) {
c.moveToLast();
}
return c;
}
This is my main class (i.e Laptops)
DbAdapter obj = new DbAdapter(this);
obj.open();
obj.insertRow("Dell1", "Dell", 345);
obj.insertRow("Hp1", "HP", 546);
obj.close();
obj.open();
Cursor c1 = obj.getAllRows();
try{
if(c1 != null){
ListView empListView = (ListView)findViewById(R.id.listView1);
ArrayList<String> data1 = new ArrayList<String>();
for(c1.moveToFirst();!c1.isAfterLast();c1.moveToNext())
{
Toast.makeText(getApplicationContext(), c1.getString(0), Toast.LENGTH_LONG).show();
}
//empListView.setAdapter(new ArrayAdapter<String>(this, android.R.layout.simple_list_item_1, data1));
}}catch(SQLException e){
e.printStackTrace();
}
obj.close();

c.moveToLast();
here is the issue
c.moveToFirst();
try this..

Try with Like This
listView = (ListView) rootView.findViewById(R.id.Assignment_VM_List);
AssignmentDatabaseConnector dao = new AssignmentDatabaseConnector(getActivity());
List<AssignmentPojo> assignments = dao.getAllAssignmentList();
AssignmentCustomAdapter assignmentCustomAdapter = new AssignmentCustomAdapter(getActivity(),
assignments, this);
listView.setAdapter(assignmentCustomAdapter);
AssignmentDatabaseConnector :
public List<AssignmentPojo> getAllAssignmentList() {
open();
List<AssignmentPojo> assignmentList = new ArrayList<AssignmentPojo>();
// Select All Query
String selectQuery = "SELECT * FROM Assignment";
Cursor cursor = database.rawQuery(selectQuery, null);
// looping through all rows and adding to list
if (cursor.moveToFirst()) { // ##Your Main Issue is Here ##
do {
AssignmentPojo assignment = new AssignmentPojo();
assignment.setAssign_Id(cursor.getString(0));
assignment.setAssign_Course(cursor.getString(1));
// Adding contact to list
assignmentList.add(assignment);
} while (cursor.moveToNext());
}
cursor.close();
database.close();
// return contact list
return assignmentList;
}
This is just a sample code you can utilize this code according to your requirements

Related

Listview from DB

I'm trying to get some data from a DB and display in a listview, but they logcat say Make sure the Cursor is initialized correctly before accessing data from it. This is my code
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_cotizacionescolumna);
lvCotizacion = (ListView)findViewById(R.id.lista_cotizaciones);
list_cotizaciones = new ArrayList<String>();
llenarLista();
eventos();
}
public void llenarLista(){
CotiCadSqlite db = new CotiCadSqlite(CotizacionesColumnnaActivity.this);
Cursor c = db.obtenerNombresColumna();
if(c.moveToFirst()){
do{
columna = c.getString(1);
list_cotizaciones.add(columna);
}while (c.moveToNext());
}
adapter = new ArrayAdapter<String>(this, android.R.layout.simple_list_item_1, list_cotizaciones);
lvCotizacion.setAdapter(adapter);
}
columna = c.getString(1);
to
c.getString(c.getColumnIndex(1))
as well
if (null != c) {
if (c.moveToFirst()) {
do {
//your code goes here
} while (c.moveToNext());
}
c.close();
try like this,
Cursor c = helper.DatabaseMethod();// retrive data
c.moveToFirst();
while (c.isAfterLast() == false)
{
String dataSaved = c.getString(c.getColumnIndex(DataBaseHelper.KEY_EMAIL));//your column index name
list_cotizaciones.add(dataSaved );
c.moveToNext();
}
c.close();
adapter = new ArrayAdapter<String>(this, android.R.layout.simple_list_item_1, list_cotizaciones);
lvCotizacion.setAdapter(adapter);

Return String[] From database

I am trying to populate my AutoCompleteTextView from a column of values in my database.
The query I am running in my database is:
// GET MEMOS
public ArrayList<String> autoCompleteMemo(String table)
{
SQLiteDatabase db = this.getReadableDatabase();
ArrayList<String> memoList = new ArrayList<String>();
String SQL_GET_MEMOS = "SELECT memo FROM " + table;
Cursor cursor = db.rawQuery(SQL_GET_MEMOS, null);
cursor.moveToFirst();
if (!cursor.isAfterLast()) {
do {
memoList.add(cursor.getString(0));
}
while (cursor.moveToNext());
}
cursor.close();
db.close();
return memoList;
}
And here is how I am attempting to set the values:
memoList = new String[db.autoCompleteMemo(table).size()];
ArrayAdapter adapter = new ArrayAdapter(this,android.R.layout.simple_list_item_1, memoList);
etMemo.setAdapter(adapter);
For some reason, this does not appear to be working. Am i converting from ArrayList to String[] properly?
Thanks
Also,
If i do something similar to this
String[] memoList = getResources().getStringArray(R.array.memoList);
and populate that in Strings.xml it works fine.
I changed my DB method to the following and it now works
public String[] autoCompleteMemo(String table) {
SQLiteDatabase db = this.getReadableDatabase();
String SQL_GET_MEMOS = "SELECT memo FROM " + table;
Cursor cursor = db.rawQuery(SQL_GET_MEMOS, null);
if (cursor.getCount() > 0) {
String[] str = new String[cursor.getCount()];
int i = 0;
while (cursor.moveToNext()) {
str[i] = cursor.getString(cursor.getColumnIndex("memo"));
i++;
}
return str;
}
else {
return new String[] {};
}
}

List View Array from Database

I have retrieved data and successfully shown it in text view.
What do I have to modify in my code to make it look like a list view?
And also how do modify my listview programatically(adding size and padding)?
Here is a part of my DBclass in selecting the items that I've displayed
getFAData() {
// TODO Auto-generated method stub
String [] columns = new String[]{Row_Name};
Cursor c = ourDB.query(db_Table, columns, null, null, null, null, null);
String res = "";
int iRow = c.getColumnIndex(Row_Name);
//int iDesc = c.getColumnIndex(Row_Desc);
//int iID = c.getColumnIndex(Row_id);
for (c.moveToFirst(); !c.isAfterLast(); c.moveToNext())
{
res = res + c.getString(iRow) + "\n";
}
return res;
}
And here is the class file:
public class FirstAid extends Activity {
#Override
protected void onCreate(Bundle savedInstanceState) {
// TODO Auto-generated method stub
super.onCreate(savedInstanceState);
setContentView(R.layout.firstaid);
displayresult();
}
public void displayresult (){
TextView tvFa = (TextView) findViewById(R.id.tvFA);
tvFa.setMovementMethod(new ScrollingMovementMethod());
DbHelper tblFa = new DbHelper(this);
tblFa.open();
String result = tblFa.getFAData();
tblFa.close();
tvFa.setText(result);
}
}
Create ArrayList int the get data function of database
public ArrayList<String> getFAData() {
ArrayList<String> comments = new ArrayList<String>();
Cursor c = ourDB.query(db_Table, columns, null, null, null, null, null);
int iRow = c.getColumnIndex(Row_Name);
cursor.moveToFirst();
while (!cursor.isAfterLast()) {
comments.add(c.getString(iRow ));
cursor.moveToNext();
}
// Make sure to close the cursor
cursor.close();
return comments;
}
in your activity retrieve data like this.
ArrayList<String> array = new ArrayList<String>();
array = tblFa.getFAData();
you need to implement a method in your dbhelper class like this
public List<String> selectAll_data() {
List<String> list = new ArrayList<String>();
Cursor cursor = this.db.query(TABLE_NAME_2, new String[] { "str" },
null , null, null, null, null);
if (cursor.moveToFirst()) {
do {
list.add(cursor.getString(0));
} while (cursor.moveToNext());
}
if (cursor != null && !cursor.isClosed()) {
cursor.close();
}
return list;
}
Now in your activity
List<String> events = dh.selectAll_data();
String[] arr = new String[events.size()];
arr = events.toArray(arr);
ArrayAdapter<String> adapter = new ArrayAdapter<String>(this,android.R.layout.simple_list_item_1, android.R.id.text1, values);
// Assign adapter to ListView
listView.setAdapter(adapter);
If you want to see a real time example check this url

How to read entire sqlite database in android

Please help me with following, I have a database which contain strings ( e.g. fotonames ).
And I want to read entire fotonames column into an arraylist.
How can I do this?
public Cursor getfotoname() throws SQLException
{
String getRT = "SELECT fotonames from "+ TABLE_NAME+";";
Cursor mCur = sqldb.rawQuery(getRT, null);
return mCur;
}
Now when you call
Cursor mCursor=null;
mCursor= DatabaseObject.getfotoname();
ArrayList<WhateverTypeYouWant> mArrayList = new ArrayList<WhateverTypeYouWant>();
for(mCursor.moveToFirst(); mCursor.moveToNext(); mCursor.isAfterLast()) {
// The Cursor is now set to the right position
mArrayList.add(mCursor.getWhateverTypeYouWant(WHATEVER_COLUMN_INDEX_YOU_WANT));
}
Have a look at this tutorial will help you
http://www.anotherandroidblog.com/2010/08/04/android-database-tutorial/
this is where you can lear how to fetch all values from one column
http://www.anotherandroidblog.com/2010/08/04/android-database-tutorial/3/#getrowasarray
or otherway is
fire query like this
public Cursor columnValues() throws SQLException{
// TODO Auto-generated method stub
Cursor mCursor = db.query(Course_Info_Table,
new String[] {Column1 , column2 },
null,null, null, null, null);
//Cursor mCursor = mDb.rawQuery("Select",null);
if (mCursor != null)
{
mCursor.moveToFirst();
}
return mCursor;
}
and receive it like
ArrayList<String> list1 = new ArrayList<String>();
ArrayList<String> list12 = new ArrayList<String>();
cursor = dbm.columnValueofCourse();
cursor.moveToFirst();
startManagingCursor(cursor);
for (int i = 0; i < cursor.getCount(); i++) {
String reciv = cursor.getString(cursor
.getColumnIndex("column1"));
String reciv3 = cursor.getString(cursor
.getColumnIndex("column2"));
list1.add(reciv);
list2.add(reciv3);
cursor.moveToNext();
}

Android SQLite get data from database to an array

i want to get the value from the cursor without the SimpleCursorAdapter part.here is the code
public Cursor queueAll(){
String[] columns = new String[]{KEY_ID, KEY_CONTENT1, KEY_CONTENT2,KEY_CONTENT3};
Cursor cursor = sqLiteDatabase.query(MYDATABASE_TABLE, columns,
null, null, null, null, null);
return cursor;
}
and the activity side code
cursor = mySQLiteAdapter.queueAll();
from = new String[]{SQLiteAdapter.KEY_ID, SQLiteAdapter.KEY_CONTENT1, SQLiteAdapter.KEY_CONTENT2, SQLiteAdapter.KEY_CONTENT3};
int[] to = new int[]{R.id.id, R.id.text1, R.id.text2,R.id.text3};
cursorAdapter =
new SimpleCursorAdapter(this, R.layout.row, cursor, from, to);
listContent.setAdapter(cursorAdapter);
while(!cursor.isAfterLast())
{
String tilt = cursor.getString(cursor.getColumnIndex(SQLiteAdapter.KEY_CONTENT1));
String pkg = cursor.getString(cursor.getColumnIndex(SQLiteAdapter.KEY_CONTENT3));
if(tilt.equals("LEFT"))
{
Log.v("LEFT",pkg);
}
else if(tilt.equals("RIGHT"))
{
Log.v("RIGHT",pkg);
}
cursor.moveToNext();
}
i am getting the pkg value correct.but i want to get the values directly from the cursor while removing SimpleCursorAdapter part the code doesn't work.
any help would be appreciated :)
You can get values without declaring adapters. Adapters are need if you want to show the data in the list widgets. So your can be the following:
cursor = mySQLiteAdapter.queueAll();
if (cursor == null) {
//check if there are errors or query just return null
}
if (cursor.moveToFirst()) {
while(!cursor.isAfterLast())
{
String tilt = cursor.getString(cursor.getColumnIndex(SQLiteAdapter.KEY_CONTENT1));
String pkg = cursor.getString(cursor.getColumnIndex(SQLiteAdapter.KEY_CONTENT3));
if(tilt.equals("LEFT"))
{
Log.v("LEFT",pkg);
}
else if(tilt.equals("RIGHT"))
{
Log.v("RIGHT",pkg);
}
cursor.moveToNext();
}
}
First you must count how many rows are in your table. Then assign that count to variable and it use to create an array. For array size you can use that count variable. Then create a for loop and use that count variable for rounds. After create your query and assign values to your arrays. 100% worked!.
int sqlcount;
Cursor mFetch;
SQLiteDatabase mydb = openOrCreateDatabase("your database name", MODE_PRIVATE, null);
mydb.execSQL("create table if not exists customer(name varchar,email varchar)");
Cursor mCount = mydb.rawQuery("select count(*) from customer", null);
mCount.moveToFirst();
sqlcount = mCount.getInt(0);
mCount.close();
String cname[] = new String[sqlcount];
String cemail[] = new String[sqlcount];
for(int i=0;i<sqlcount;i++) {
mFetch= mydb.rawQuery("select name,email from customer", null);
mFetch.moveToPosition(i);
cname[i] = mFetch.getString(0);
cemail[i] = mFetch.getString(1);
}
mFetch.close();
Toast.makeText(MainActivity.this,String.valueOf(cname[0]),Toast.LENGTH_SHORT).show();
Toast.makeText(MainActivity.this,String.valueOf(cemail[1]),Toast.LENGTH_SHORT).show();

Categories

Resources