I have seen a lot of similar problems here, but none solved my problem.
Im making an app that put the contents of a XML in a database. Everything is working fine but when I open the app for a second time more and more values are added. I was trying to drop table, drop database, and even deleting the file and none of these worked.
Now I added this code and the app is only parsing the LAST line of the xml to the database, and I really dont know why this happens.
myDatabase.execSQL("DROP TABLE " + DATABASE_TABLE);
myDatabase.execSQL("CREATE TABLE " + DATABASE_TABLE + " (" +
KEY_ID + " INTEGER PRIMARY KEY AUTOINCREMENT, " +
KEY_NAME + " TEXT NOT NULL, " +
KEY_LINK + " TEXT NOT NULL);"
);
Full code:
XMLHelper:
package com.example.partedoxml;
import java.io.InputStream;
import java.net.URL;
import java.util.ArrayList;
import javax.xml.parsers.SAXParser;
import javax.xml.parsers.SAXParserFactory;
import org.xml.sax.Attributes;
import org.xml.sax.InputSource;
import org.xml.sax.SAXException;
import org.xml.sax.XMLReader;
import org.xml.sax.helpers.DefaultHandler;
import android.util.Log;
public class XMLHelper extends DefaultHandler {
private String URL_MAIN = "http://he4dless.webege.com/packages.xml";
String TAG = "XMLHelper";
Boolean currTag = false;
String currTagVal = "";
public PostValue menes = null;
public ArrayList<PostValue> he4dless = new ArrayList<PostValue>();
public void get() {
try{
SAXParserFactory factory = SAXParserFactory.newInstance();
SAXParser mSaxParser = factory.newSAXParser();
XMLReader mXmlReader = mSaxParser.getXMLReader();
mXmlReader.setContentHandler(this);
InputStream mInputStream = new URL(URL_MAIN).openStream();
mXmlReader.parse(new InputSource(mInputStream));
}catch(Exception e){
Log.e(TAG, "Exeption:"+e.getMessage());
}
}
#Override
public void characters(char[] ch, int start, int length)
throws SAXException {
if(currTag){
currTagVal = currTagVal + new String(ch, start, length);
currTag = false;
}
}
#Override
public void endElement(String uri, String localName, String qName)
throws SAXException {
currTag = false;
//if(localName.equalsIgnoreCase("id"))
//packages.setId(currTagVal);
if(localName.equalsIgnoreCase("name"))
menes.setName(currTagVal);
else if(localName.equalsIgnoreCase("link"))
menes.setLink(currTagVal);
else if(localName.equalsIgnoreCase("menes"))
he4dless.add(menes);
}
#Override
public void startElement(String uri, String localName, String qName,
Attributes attributes) throws SAXException {
Log.i(TAG, "TAG:"+localName);
currTag = true;
currTagVal = "";
if(localName.equals("menes"))
menes = new PostValue();
}
}
SQLHelper:
package com.example.partedoxml;
import java.io.File;
import android.content.ContentValues;
import android.content.Context;
import android.database.sqlite.SQLiteDatabase;
import android.database.sqlite.SQLiteDatabase.CursorFactory;
import android.database.sqlite.SQLiteOpenHelper;
public class SQLHelper {
public static final String DATABASE_NAME = "he4dless";
public static final String DATABASE_TABLE = "menes";
public static final int DATABASE_VERSION = 1;
public static final String KEY_ID = "_id";
public static final String KEY_NAME = "name";
public static final String KEY_LINK = "link";
public static final String TAG_1 = "tag1";
public static final String TAG_2 = "tag2";
public static final String TAG_3 = "tag3";
private DbHelper myHelper;
private Context myContext;
private SQLiteDatabase myDatabase;
private static class DbHelper extends SQLiteOpenHelper {
public DbHelper(Context context) {
super(context, DATABASE_NAME, null, DATABASE_VERSION);
// TODO Auto-generated constructor stub
}
#Override
public void onCreate(SQLiteDatabase db) {
db.execSQL("CREATE TABLE " + DATABASE_TABLE + " (" +
KEY_ID + " INTEGER PRIMARY KEY AUTOINCREMENT, " +
KEY_NAME + " TEXT NOT NULL, " +
KEY_LINK + " TEXT NOT NULL);"
//TAG_1 + " TEXT NOT NULL, " +
//TAG_2 + " TEXT NOT NULL, " +
//TAG_3 + " TEXT NOT NULL);"
);
}
#Override
public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {
db.execSQL("DROP TABLE IF EXISTS " + DATABASE_TABLE);
onCreate(db);
}
}
public SQLHelper(Context c){
myContext = c;
}
public SQLHelper open(){
myHelper = new DbHelper(myContext);
myDatabase = myHelper.getWritableDatabase();
myDatabase.execSQL("DROP TABLE " + DATABASE_TABLE);
myDatabase.execSQL("CREATE TABLE " + DATABASE_TABLE + " (" +
KEY_ID + " INTEGER PRIMARY KEY AUTOINCREMENT, " +
KEY_NAME + " TEXT NOT NULL, " +
KEY_LINK + " TEXT NOT NULL);"
);
return this;
}
public void close(){
myHelper.close();
}
public long create(String name, String link) {
ContentValues cv = new ContentValues();
cv.put(KEY_NAME, name);
cv.put(KEY_LINK, link);
return myDatabase.insert(DATABASE_TABLE, null, cv);
}
}
MainActivity:
package com.example.partedoxml;
import android.support.v7.app.ActionBarActivity;
import android.app.ProgressDialog;
import android.content.Context;
import android.os.AsyncTask;
import android.os.Bundle;
import android.view.Menu;
import android.view.MenuItem;
import android.widget.TextView;
public class MainActivity extends ActionBarActivity {
TextView tv;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
tv = (TextView)findViewById(R.id.tv);
new PostAsync().execute();
}
class PostAsync extends AsyncTask<Void, Void, Void>{
ProgressDialog pd;
XMLHelper helper;
#Override
protected void onPreExecute() {
pd = ProgressDialog.show(MainActivity.this, "Esta porra esta carregando", "Baixando o XML", true, false);
}
#Override
protected Void doInBackground(Void... params) {
helper = new XMLHelper();
helper.get();
return null;
}
#Override
protected void onPostExecute(Void result) {
StringBuilder builder = new StringBuilder();
for(PostValue post : helper.he4dless){
//builder.append("\nId: "+ post.getId());
builder.append("\nName: "+ post.getName());
builder.append("\nSection: "+ post.getLink());
builder.append("\n");
String name = post.getName();
String link = post.getLink();
SQLHelper entry = new SQLHelper(MainActivity.this);
entry.open();
entry.create(name, link);
entry.close();
}
tv.setText(builder.toString());
pd.dismiss();
}
}
#Override
public boolean onCreateOptionsMenu(Menu menu) {
// Inflate the menu; this adds items to the action bar if it is present.
getMenuInflater().inflate(R.menu.main, menu);
return true;
}
#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();
if (id == R.id.action_settings) {
return true;
}
return super.onOptionsItemSelected(item);
}
}
I will be very glad if someone solves this problem
Your open() drops and recreates the table, and you reopen the database in each for loop iteration.
Leave schema setup to the helper callbacks such as onCreate(). Also, you don't need to reopen the database inside the loop.
The problem you have is that the method open() in SQLHelper performs the following:
//You are calling here an instance of your helper. Good.
myHelper = new DbHelper(myContext);
//This step will get you a database. See my explanatino below to understand what happens here
myDatabase = myHelper.getWritableDatabase();
//THIS LINES SHOULD BE REMOVED
//In this step you will delete the database (actually only the table) and ALL data
myDatabase.execSQL("DROP TABLE " + DATABASE_TABLE);
//You create the same database again.
myDatabase.execSQL("CREATE TABLE " + DATABASE_TABLE + " (" +
KEY_ID + " INTEGER PRIMARY KEY AUTOINCREMENT, " +
KEY_NAME + " TEXT NOT NULL, " +
KEY_LINK + " TEXT NOT NULL);"
);
You are actually doing some work twice. When you try to get the writable database you are already calling the method onCreate if the database does not exists. So that you create the database, you delete it, and you create back again empty.
Your code should be the following in open() method and everything should work:
public SQLHelper open(){
myHelper = new DbHelper(myContext);
myDatabase = myHelper.getWritableDatabase();
Finally, I would like also to highlight a potential problem. On the method OnUpgrade you are setting up that your database is also deleted and created back again when you change the version of the database. That means that everytime you modify the value of DATABASE_VERSION the complete data will dissapear.
If you are interested in modifying a value already in the database, you can update it, for example, for the item with KEY_NAME name you can update the value of KEY_LINK adding link2:
public int create(String name, String link2) {
ContentValues cv = new ContentValues();
cv.put(KEY_LINK, link2);
return myDatabase.update(DATABASE_TABLE, cv, KEY_NAME + "=" + name, null );
}
Related
I want all edit text content that I have saved in SQL to be displayed on the edit bills activity when I click on the list item, but I am only able to retrieve the name and display it again in the intent. Rather than saving another data it should update the record with the new data if I save the existing record another time in the editbills_activity.
Here is my DBAdapter.java
package com.example.dhruv.bills;
import android.content.ContentValues;
import android.content.Context;
import android.database.Cursor;
import android.database.SQLException;
import android.database.sqlite.SQLiteDatabase;
import android.database.sqlite.SQLiteOpenHelper;
import android.util.Log;
public class DBAdapter {
public static final String KEY_ROWID = "id";
public static final String KEY_NAME = "name";
public static final String KEY_AMOUNT = "amount";
public static final String KEY_DUEDATE = "duedate";
private static final String TAG = "DBAdapter";
private static final String DATABASE_NAME = "billsdb";
private static final String DATABASE_TABLE = "bills";
private static final int DATABASE_VERSION = 2;
private static final String DATABASE_CREATE =
"create table if not exists assignments (id integer primary key autoincrement, "
+ "name VARCHAR not null, amount VARCHAR, duedate date );";
// Replaces DATABASE_CREATE using the one source definition
private static final String TABLE_CREATE =
"CREATE TABLE IF NOT EXISTS " + DATABASE_TABLE + "(" +
KEY_ROWID + " INTEGER PRIMARY KEY, " + // AUTOINCREMENT NOT REQD
KEY_NAME + " DATE NOT NULL, " +
KEY_AMOUNT + " VARCHAR ," +
KEY_DUEDATE + " DATE " +
")";
private final Context context;
private DatabaseHelper DBHelper;
private SQLiteDatabase db;
public DBAdapter(Context ctx)
{
this.context = ctx;
DBHelper = new DatabaseHelper(context);
}
private static class DatabaseHelper extends SQLiteOpenHelper
{
DatabaseHelper(Context context)
{
super(context, DATABASE_NAME, null, DATABASE_VERSION);
}
#Override
public void onCreate(SQLiteDatabase db)
{
db.execSQL(TABLE_CREATE); // NO need to encapsulate in try clause
}
#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 contacts"); //????????
db.execSQL("DROP TABLE IF EXISTS " + DATABASE_TABLE);
onCreate(db);
}
}
//---opens the database---
public DBAdapter open() throws SQLException
{
db = DBHelper.getWritableDatabase();
return this;
}
//---closes the database---
public void close()
{
DBHelper.close();
}
//---insert a record into the database---
public long insertRecord(String name, String amount, String duedate)
{
ContentValues initialValues = new ContentValues();
initialValues.put(KEY_NAME, name);
initialValues.put(KEY_AMOUNT, amount);
initialValues.put(KEY_DUEDATE, duedate);
//return db.insert(DATABASE_TABLE, null, initialValues);
// Will return NULL POINTER EXCEPTION as db isn't set
// Replaces commented out line
return DBHelper.getWritableDatabase().insert(DATABASE_TABLE,
null,
initialValues
);
}
//---deletes a particular record---
public boolean deleteContact(long rowId)
{
return db.delete(DATABASE_TABLE, KEY_ROWID + "=" + rowId, null) > 0;
}
//---retrieves all the records--- SEE FOLLOWING METHOD
public Cursor getAllRecords()
{SQLiteDatabase db = DBHelper.getWritableDatabase();
String query ="SELECT * FROM " + DATABASE_TABLE;
Cursor data = db.rawQuery(query,null);
return data;
}
//As per getAllRecords but using query convenience method
public Cursor getAllAsCursor() {
return DBHelper.getWritableDatabase().query(
DATABASE_TABLE,
null,null,null,null,null,null
);
}
public Cursor getItemID(String name) {
SQLiteDatabase db = DBHelper.getWritableDatabase();
String query = "SELECT " + KEY_ROWID + " FROM " + DATABASE_TABLE +
" WHERE " + KEY_NAME + " = '" + name + "'";
Cursor data = db.rawQuery(query, null);
return data;
}
//---retrieves a particular record--- THIS WILL NOT WORK - NO SUCH TABLE
/* public Cursor getRecord()
{String query1 ="SELECT * FROM" + KEY_TITLE;
Cursor mCursor = db.rawQuery(query1,null);
if (mCursor != null) {
mCursor.moveToFirst();
}
return mCursor;
}*/
// Retrieve a row (single) according to id
public Cursor getRecordById(long id) {
return DBHelper.getWritableDatabase().query(
DATABASE_TABLE,
null,
KEY_ROWID + "=?",
new String[]{String.valueOf(id)},
null,null,null
);
}
//---updates a record---
/* public boolean updateRecord(long rowId, String name, String amount, String duedate)
{
ContentValues args = new ContentValues();
args.put(KEY_NAME, name);
args.put(KEY_AMOUNT, amount);
args.put(KEY_DUEDATE, duedate);
String whereclause = KEY_ROWID + "=?";
String[] whereargs = new String[]{String.valueOf(rowId)};
// Will return NULL POINTER EXCEPTION as db isn't set
//return db.update(DATABASE_TABLE, args, KEY_ROWID + "=" + rowId, null) > 0;
// Replaces commented out line
return DBHelper.getWritableDatabase().update(DATABASE_TABLE,
args,
whereclause,
whereargs
) > 0;
}*/
}
Here is my Bills.java
(MainActivity)
Problem: Bills.java has the list view that shows the intent whenever the item in list view is clicked, but it does not put the amount and date or update the record. Instead it saves another record.
Solution: I want to retrieve it and display all (name ,amount,duedate) and instead of saving another record it should update it.
package com.example.dhruv.bills;
import android.content.Intent;
import android.database.Cursor;
import android.os.Bundle;
import android.support.design.widget.FloatingActionButton;
import android.support.design.widget.Snackbar;
import android.support.v7.app.AppCompatActivity;
import android.support.v7.widget.RecyclerView;
import android.support.v7.widget.Toolbar;
import android.util.Log;
import android.view.View;
import android.view.Menu;
import android.view.MenuItem;
import android.widget.AdapterView;
import android.widget.ArrayAdapter;
import android.widget.ListAdapter;
import android.widget.ListView;
import android.widget.Toast;
import java.util.ArrayList;
public class bills extends AppCompatActivity {
DBAdapter dbAdapter;
ListView mrecycleview;
private static final String TAG ="assignments";
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_bills);
Toolbar toolbar = (Toolbar) findViewById(R.id.toolbar);
setSupportActionBar(toolbar);
mrecycleview =(ListView) findViewById(R.id.mRecycleView);
dbAdapter = new DBAdapter(this);
// mlistview();
FloatingActionButton fab = (FloatingActionButton) findViewById(R.id.fab);
fab.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View view) {
Intent i = new Intent(getApplicationContext(),Editbills.class);
startActivity(i);
}
});
mlistview();
}
#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_bills, 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);
}
private void mlistview(){
Log.d(TAG,"mlistview:Display data in listview");
Cursor mCursor = dbAdapter.getAllRecords();
ArrayList<String> listData = new ArrayList<>();
while (mCursor.moveToNext()){
listData.add(mCursor.getString(1));
}
ListAdapter adapter = new ArrayAdapter<>(this,android.R.layout.simple_list_item_1,listData);
mrecycleview.setAdapter(adapter);
mrecycleview.setOnItemClickListener(new AdapterView.OnItemClickListener() {
#Override
public void onItemClick(AdapterView<?> adapterView, View view, int i, long l) {
String name = adapterView.getItemAtPosition(i).toString();
Log.d(TAG, "onItemClick: You Clicked on " + name);
Cursor data = dbAdapter.getItemID(name); //get the id associated with that name
int itemID = -1;
while(data.moveToNext()){
itemID = data.getInt(0);
}
if(itemID > -1){
Log.d(TAG, "onItemClick: The ID is: " + itemID);
Intent editScreenIntent = new Intent(bills.this, Editbills.class);
editScreenIntent.putExtra("id",itemID);
editScreenIntent.putExtra("name",name);
startActivity(editScreenIntent);
}
else{
}
}
});
}
}
here is my editbills.java code
package com.example.dhruv.bills;
import android.content.ContentValues;
import android.content.Intent;
import android.database.Cursor;
import android.database.sqlite.SQLiteDatabase;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.util.Log;
import android.view.View;
import android.widget.ArrayAdapter;
import android.widget.Button;
import android.widget.EditText;
import android.widget.ListView;
import android.widget.Toast;
import java.util.ArrayList;
public class Editbills extends AppCompatActivity {
Button button;
private static final String Tag= "assignments";
DBAdapter db = new DBAdapter(this);
private String selectedName;
private int selectedID;
DBAdapter dbAdapter;
private EditText editText,editText2,editText3;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_editbills);
button=(Button)findViewById(R.id.button);
editText =(EditText)findViewById(R.id.editText);
editText2=(EditText)findViewById(R.id.editText2);
editText3 =(EditText)findViewById(R.id.editText3);
//get the intent extra from the ListDataActivity
Intent receivedIntent = getIntent();
//now get the itemID we passed as an extra
selectedID = receivedIntent.getIntExtra("id",-1); //NOTE: -1 is just the default value
//now get the name we passed as an extra
selectedName = receivedIntent.getStringExtra("name");
//set the text to show the current selected name
editText.setText(selectedName);
button.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View view) {
Log.d("test", "adding");
db.open();
long id = db.insertRecord(editText.getText().toString(), editText2.getText().toString(), editText3.getText().toString());
db.close();
Toast.makeText(Editbills.this," Added", Toast.LENGTH_LONG).show();
Intent q = new Intent(getApplicationContext(),bills.class);
startActivity(q);
}
});
}
}
There are two parts/questions.
First to retrieve the data, so that it can be displayed in the editbills activity, you can utilise the row's id that is passed to the activity in conjunction with the getRecordById method.
I'd suggest that adding a method to the editbills class will simplyfy matters.
private void populateDisplay(int id) {
Cursor csr = dbAdapter.getRecordById(id);
if (csr.moveToFirst()) {
editText.setText(csr.getString(csr.getColumnIndex(DBAdapter.KEY_NAME)));
editText2.setText(csr.getString(csr.getColumnIndex(DBAdapter.KEY_AMOUNT)));
editText3.setText(csr.getString(csr.getColumnIndex(DBAdapter.KEY_DUEDATE)));
}
csr.close();
}
You could invoke the above method after retrieving the id from the Intent using :-
populateDisplay(selectedID);
To update based upon the content's of the EditTexts un-comment the updateRecord method in DBAdapter.java and the change :-
button.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View view) {
Log.d("test", "adding");
db.open();
long id = db.insertRecord(editText.getText().toString(), editText2.getText().toString(), editText3.getText().toString());
db.close();
Toast.makeText(Editbills.this," Added", Toast.LENGTH_LONG).show();
Intent q = new Intent(getApplicationContext(),bills.class);
startActivity(q);
}
});
to :-
mButton.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
if (dbAdapter.updateRecord(
selectedId,
editText.getText().toString(),
editText2.getText().toString(),
editText3.getText().toString())
) {
Log.d("TEST","Row successfully updated.");
Toast.makeText(getApplicationContext(),"Row Updated.",Toast.LENGTH_LONG).show();
populateDisplay(selectedId);
} else {
Toast.makeText(getApplicationContext(),"Row not Updated",Toast.LENGTH_LONG).show();
}
Intent q = new Intent(getApplicationContext(),bills.class);
startActivity(q);
}
});
You will additionally have to add a line initialise the dbAdapter i.e. dbAdapter = new DBAdapter(this); i.d suggest adding this line immediately after the line setContentView(R.layout.activity_editbills);
Note the above code is in-principle and has not been thoroughly tested so it may contains errors.
Edit complete working example :-
The following code is basically an implementation of the above, except modified to utilise a Bill class. Rather than an ArrayList<String> as the source for the Adapter it has ArrayList<Bill>.
Thus all the data (id, name, amount and duedate) is available.
You should notice that I've overridden the toString method to return a String that combines the name, amount and duedate. The ArrayAdapter uses the object's toString method to populate the view.
Saying that the critical value is the rowid or an alias of rowid as this can be used to identify a row even if the other data is identical (as would happen when running this example more than once due to the addSomeData method). Hence, only the id is extracted and passed to the Editbills activity when an item in the list is long clicked (changed from just clicked to reduce the potential for accidental use).
Bill.java
public class Bill {
private long id;
private String name;
private String amount;
private String duedate;
public Bill(long id, String name, String amount, String duedate) {
this.id = id;
this.name = name;
this.amount = amount;
this.duedate = duedate;
}
/*
Note if this Constructor used then setId should be used
*/
public Bill(String name, String amount, String duedate) {
new Bill(0,name,amount,duedate);
}
public long getId() {
return id;
}
public void setId(long id) {
this.id = id;
}
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
public String getAmount() {
return amount;
}
public void setAmount(String amount) {
this.amount = amount;
}
public String getDuedate() {
return duedate;
}
public void setDuedate(String duedate) {
this.duedate = duedate;
}
/*
As ArrayAdapter uses toString method change this
to return all items
*/
#Override
public String toString() {
return name + " " + amount + " " + duedate;
}
}
MainActivity.java
This is the equivalent to your Bills.java without a lot of the bloat such as FAB. :-
public class MainActivity extends AppCompatActivity {
public static final String ID_INTENTEXTRA = DBAdapter.KEY_ROWID + "_INTENTEXTRA"; //<<<< ADDED
DBAdapter mDBAdapter;
Cursor mCsr;
ListView mrecycleview;
ArrayAdapter adapter; //<<<< NOT ListAdapter
Context context; // ADDED
private static final String TAG ="assignments";
ArrayList<Bill> mBillList = new ArrayList<>();
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
context = this;
mrecycleview = this.findViewById(R.id.mRecycleView);
mDBAdapter = new DBAdapter(this);
addSomeData();
adapter = new ArrayAdapter<Bill>(
this,
android.R.layout.simple_list_item_1,
mBillList
);
mrecycleview.setAdapter(adapter);
mrecycleview.setOnItemLongClickListener(new AdapterView.OnItemLongClickListener() {
#Override
public boolean onItemLongClick(AdapterView<?> parent, View view, int position, long id) {
Bill b = (Bill) adapter.getItem(position);
Intent i = new Intent(context,Editbills.class);
i.putExtra(ID_INTENTEXTRA,b.getId()); //Get ID
startActivity(i);
return true;
}
});
rebuildBillList();
}
//<<<< ADDED Method to refresh the ListView resumed
#Override
protected void onResume() {
super.onResume();
rebuildBillList();
}
// Add some data (note will add 2 rows each time it is run)
private void addSomeData() {
mDBAdapter.insertRecord("Bill1","2018-10-02","English");
mDBAdapter.insertRecord("Bill2","2018-09-03","Mathematics");
mDBAdapter.insertRecord("Bill3","2018-11-04", "Geography");
}
public void rebuildBillList() {
mBillList.clear();
mCsr = mDBAdapter.getAllAsCursor();
while (mCsr.moveToNext()) {
mBillList.add(new Bill(
mCsr.getLong(mCsr.getColumnIndex(DBAdapter.KEY_ROWID)),
mCsr.getString(mCsr.getColumnIndex(DBAdapter.KEY_NAME)),
mCsr.getString(mCsr.getColumnIndex(DBAdapter.KEY_AMOUNT)),
mCsr.getString(mCsr.getColumnIndex(DBAdapter.KEY_DUEDATE))
)
);
}
adapter.notifyDataSetChanged();
}
}
Note the above adds 3 rows each time it is run.
Editbills.java
public class Editbills extends AppCompatActivity {
Button button;
private static final String Tag = "assignments";
DBAdapter db = new DBAdapter(this);
private String selectedName;
private long selectedID;
DBAdapter dbAdapter;
private EditText editText,editText2,editText3;
Context context;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_editbills);
context = this;
dbAdapter = new DBAdapter(this); //<<<< ADDED
button=(Button)findViewById(R.id.button);
editText =(EditText)findViewById(R.id.edittext);
editText2=(EditText)findViewById(R.id.edittext2);
editText3 =(EditText)findViewById(R.id.edittext3);
//get the intent extra from the ListDataActivity
Intent receivedIntent = getIntent();
//now get the itemID we passed as an extra
selectedID = receivedIntent.getLongExtra(MainActivity.ID_INTENTEXTRA,-1L); //NOTE: -1 is just the default value
populateDisplay(selectedID);
//now get the name we passed as an extra
//selectedName = receivedIntent.getStringExtra("name");
//set the text to show the current selected name
//editText.setText(selectedName); <<<< commented out
button.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View view) {
/*
Log.d("test", "adding");
db.open();
long id = db.insertRecord(editText.getText().toString(), editText2.getText().toString(), editText3.getText().toString());
db.close();
Toast.makeText(Editbills.this," Added", Toast.LENGTH_LONG).show();
*/
/*
* <<<< Not the way as it ends/closes the existing activity
Intent q = new Intent(getApplicationContext(),MainActivity.class);
startActivity(q);
*/
String toast = "Updated.";
if (dbAdapter.updateRecord(selectedID,
editText.getText().toString(),
editText2.getText().toString(),
editText3.getText().toString())) {
} else {
toast = "Not Updated.";
}
Toast.makeText(context,toast,Toast.LENGTH_LONG).show();
finish(); //<<<< ends/closes this activity and returns to calling activity
}
});
}
private void populateDisplay(long id) {
Cursor csr = dbAdapter.getRecordById(id);
if (csr.moveToFirst()) {
editText.setText(csr.getString(csr.getColumnIndex(DBAdapter.KEY_NAME)));
editText2.setText(csr.getString(csr.getColumnIndex(DBAdapter.KEY_AMOUNT)));
editText3.setText(csr.getString(csr.getColumnIndex(DBAdapter.KEY_DUEDATE)));
}
csr.close();
}
}
Basically as per the original answer.
DBAdapter.java
public class DBAdapter {
public static final String KEY_ROWID = "id";
public static final String KEY_NAME = "name";
public static final String KEY_AMOUNT = "amount";
public static final String KEY_DUEDATE = "duedate";
private static final String TAG = "DBAdapter";
private static final String DATABASE_NAME = "billsdb";
private static final String DATABASE_TABLE = "bills";
private static final int DATABASE_VERSION = 2;
// Replaces DATABASE_CREATE using the one source definition
private static final String TABLE_CREATE =
"CREATE TABLE IF NOT EXISTS " + DATABASE_TABLE + "(" +
KEY_ROWID + " INTEGER PRIMARY KEY, " + // AUTOINCREMENT NOT REQD
KEY_NAME + " DATE NOT NULL, " +
KEY_AMOUNT + " VARCHAR ," +
KEY_DUEDATE + " DATE " +
")";
private Context context;
private DatabaseHelper DBHelper;
private SQLiteDatabase db;
public DBAdapter(Context ctx)
{
this.context = ctx;
DBHelper = new DatabaseHelper(context);
}
private static class DatabaseHelper extends SQLiteOpenHelper
{
DatabaseHelper(Context context)
{
super(context, DATABASE_NAME, null, DATABASE_VERSION);
}
#Override
public void onCreate(SQLiteDatabase db)
{
db.execSQL(TABLE_CREATE); // NO need to encapsulate in try clause
}
#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 contacts"); //????????
db.execSQL("DROP TABLE IF EXISTS " + DATABASE_TABLE);
onCreate(db);
}
}
//---opens the database--- NOT NEEDED
public DBAdapter open() throws SQLException
{
db = DBHelper.getWritableDatabase();
return this;
}
//---closes the database--- NOT NEEDED
public void close()
{
DBHelper.close();
}
//---insert a record into the database---
public long insertRecord(String name, String amount, String duedate)
{
ContentValues initialValues = new ContentValues();
initialValues.put(KEY_NAME, name);
initialValues.put(KEY_AMOUNT, amount);
initialValues.put(KEY_DUEDATE, duedate);
return DBHelper.getWritableDatabase().insert(DATABASE_TABLE,
null,
initialValues
);
}
//---deletes a particular record---
public boolean deleteContact(long rowId)
{
return db.delete(DATABASE_TABLE, KEY_ROWID + "=" + rowId, null) > 0;
}
//---retrieves all the records--- SEE FOLLOWING METHOD
public Cursor getAllRecords()
{SQLiteDatabase db = DBHelper.getWritableDatabase();
String query ="SELECT * FROM " + DATABASE_TABLE;
Cursor data = db.rawQuery(query,null);
return data;
}
//As per getAllRecords but using query convenience method
public Cursor getAllAsCursor() {
return DBHelper.getWritableDatabase().query(
DATABASE_TABLE,
null,null,null,null,null,null
);
}
public Cursor getItemID(String name) {
SQLiteDatabase db = DBHelper.getWritableDatabase();
String query = "SELECT " + KEY_ROWID + " FROM " + DATABASE_TABLE +
" WHERE " + KEY_NAME + " = '" + name + "'";
Cursor data = db.rawQuery(query, null);
return data;
}
// Retrieve a row (single) according to id
public Cursor getRecordById(long id) {
return DBHelper.getWritableDatabase().query(
DATABASE_TABLE,
null,
KEY_ROWID + "=?",
new String[]{String.valueOf(id)},
null,null,null
);
}
//---updates a record---
public boolean updateRecord(long rowId, String name, String amount, String duedate) {
ContentValues args = new ContentValues();
args.put(KEY_NAME, name);
args.put(KEY_AMOUNT, amount);
args.put(KEY_DUEDATE, duedate);
String whereclause = KEY_ROWID + "=?";
String[] whereargs = new String[]{String.valueOf(rowId)};
return DBHelper.getWritableDatabase().update(DATABASE_TABLE,
args,
whereclause,
whereargs
) > 0;
}
}
Basically as was except that upDateRecord has been un-commented, again as per the original answer.
Results
1st Run - MainActivity (Bills) :-
Long Click Bill2 (note changed from Click as Long Click is less prone to accidental use)
Change data (Update button not clicked)
Update Button Clicked (Toast was Updated.)
Note use of finish() to return to the invoking activity and then the use of onResume to refresh the list according to the updated data (possibly your next question).
using startActivity will simply result in issues.
Note Values are date and course rather then amount and duedate because I didn't change the values in the addSomeData method (easily done).
the actual data itself is irrelevant to the process.
Hi i am trying to make give connection with SQLlite database. Code is looking fine but database table is not created.App is running well but database is not created. Any suggestions?? My codes:
DatabaseManager.java
package com.step2rock.www.database;
import android.content.ContentValues;
import android.content.Context;
import android.database.sqlite.SQLiteDatabase;
import android.database.sqlite.SQLiteOpenHelper;
import android.util.Log;
import android.widget.Toast;
import com.step2rock.www.model.User;
/**
* Created by Sushimz on 5/15/2016.
*/
public class DatabaseManager extends SQLiteOpenHelper {
Context context;
// All Static variables
// Database Version
private static final int DATABASE_VERSION = 1;
// Database Name
private static final String DATABASE_NAME = "photography";
// Users table name
private static final String TABLE_USERS = "users";
//blog table name
private static final String TABLE_BLOG = "blog";
// Users Table Columns names
private static final String KEY_USER_ID = "id";
private static final String KEY_USER_first_NAME = "f_name";
private static final String KEY_USER_last_NAME = "l_name";
private static final String KEY_USER_PASS = "password";
private static final String KEY_USER_PIC = "profilepic";
private static final String KEY_USER_Address = "address";
private static final String KEY_USER_Exp = "exp_level";
private static final String KEY_USER_link = "link";
private static final String KEY_USER_TYPE = "type";
// Blog Table Columns names
private static final String KEY_Blog_ID = "id";
private static final String KEY_Blog_Title = "blog_tilte";
private static final String KEY_Blog_Desc = "blog_desc";
private static final String KEY_Blog_Image = "blog_image";
private static final String KEY_Blog_Link = "blog_link";
public DatabaseManager(Context context) {
super(context, DATABASE_NAME, null, DATABASE_VERSION);
Log.d("users",TABLE_USERS);
Log.d("blog",TABLE_BLOG);
}
#Override
public void onCreate(SQLiteDatabase db) {
String CREATE_USERS_TABLE = "CREATE TABLE " + TABLE_USERS
+ "("
+ KEY_USER_ID + " INTEGER PRIMARY KEY,"
+ KEY_USER_first_NAME + " TEXT,"
+ KEY_USER_last_NAME + " TEXT,"
+ KEY_USER_PASS + " TEXT,"
+ KEY_USER_PIC + " TEXT,"
+ KEY_USER_Address + " TEXT,"
+ KEY_USER_Exp + " TEXT,"
+ KEY_USER_link + " TEXT,"
+ KEY_USER_TYPE + " TEXT,"
+ ")";
db.execSQL(CREATE_USERS_TABLE);
String CREATE_BLOG_TABLE = "CREATE TABLE " + TABLE_BLOG
+ "("
+ KEY_Blog_ID + " INTEGER PRIMARY KEY,"
+ KEY_Blog_Title + " TEXT,"
+ KEY_Blog_Desc + " TEXT,"
+ KEY_Blog_Image + " TEXT,"
+ KEY_Blog_Link + " TEXT ,"
+ " FOREIGN KEY(" + KEY_USER_ID + ") REFERENCES Users(id) ON DELETE CASCADE "
+ ")";
db.execSQL(CREATE_BLOG_TABLE);
Toast.makeText(this.context, "AAA", Toast.LENGTH_SHORT).show();
}
#Override
public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {
// Drop older table if existed
db.execSQL("DROP TABLE IF EXISTS " + TABLE_USERS);
db.execSQL("DROP TABLE IF EXISTS " + TABLE_BLOG);
// Create tables again
onCreate(db);
}
public void resetDB() {
SQLiteDatabase db = this.getWritableDatabase();
db.execSQL("DROP TABLE IF EXISTS " + TABLE_USERS);
db.execSQL("DROP TABLE IF EXISTS " + TABLE_BLOG);
// Create tables again
onCreate(db);
}
/**
* All CRUD(Create, Read, Update, Delete) Operations
*/
// Adding new USER
public int addUser(User user) {
SQLiteDatabase db = this.getWritableDatabase();
ContentValues values = new ContentValues();
values.put(KEY_USER_ID, user.get_user_id());
values.put(KEY_USER_first_NAME, user.get_first_name());
values.put(KEY_USER_last_NAME, user.get_last_name());
values.put(KEY_USER_PASS, user.get_user_pass());
values.put(KEY_USER_PIC, user.get_user_pic());
values.put(KEY_USER_Address, user.get_user_address());
values.put(KEY_USER_Exp, user.get_user_exp());
values.put(KEY_USER_link, user.get_user_link());
values.put(KEY_USER_TYPE, user.get_user_type());
// Inserting Row
int last_id = (int) db.insert(TABLE_USERS, null, values);
db.close(); // Closing database connection
return last_id;
}
// Updating single User
public int updateUser(User user) {
SQLiteDatabase db = this.getWritableDatabase();
ContentValues values = new ContentValues();
values.put(KEY_USER_ID, user.get_user_id());
values.put(KEY_USER_first_NAME, user.get_first_name());
values.put(KEY_USER_last_NAME, user.get_last_name());
values.put(KEY_USER_PASS, user.get_user_pass());
values.put(KEY_USER_PIC, user.get_user_pic());
values.put(KEY_USER_Address, user.get_user_address());
values.put(KEY_USER_Exp, user.get_user_exp());
values.put(KEY_USER_link, user.get_user_link());
values.put(KEY_USER_TYPE, user.get_user_type());
// updating row
return db.update(TABLE_USERS, values, KEY_USER_ID + " = ?",
new String[]{String.valueOf(user.get_user_id())});
}
}
RegistrationActivity.java
package com.step2rock.www.crudproject;
import android.os.Bundle;
import android.support.v7.app.AlertDialog;
import android.support.v7.app.AppCompatActivity;
import android.view.View;
import android.widget.Button;
import android.widget.Toast;
import com.step2rock.www.database.DatabaseManager;
/**
* Created by Sushimz on 5/15/2016.
*/
public class RegistrationActivity extends AppCompatActivity {
Button btnSaveRecord;
DatabaseManager databaseManager;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.registration_activity);
btnSaveRecord = (Button) findViewById(R.id.btnSaveRecord);
databaseManager = new DatabaseManager(RegistrationActivity.this);
btnSaveRecord.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View arg0) {
Toast toast = Toast.makeText(RegistrationActivity.this,"welcome",Toast.LENGTH_SHORT);
toast.show();
}
});
}
}
The SQLiteOpenHelper you have there looks quite good.
Confusingly onCreate(...) is never called because it does not have the same behavior as an Activity.onCreate(...).
From the documentation:
Called when the database is created for the first time. This is where the creation of tables and the initial population of the tables should happen.
As far as I understand your code, the database is never created (unless you did it elsewhere). To create it you need to try to execute something on the database. For example, try to add a User on your button click. This will call getWriteableDdatabase() and should invoke onCreate(...):
btnSaveRecord.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View arg0) {
int id = databaseManager.addUser(new User(...));
Toast toast = Toast.makeText(RegistrationActivity.this,"Welcome User #" + id,Toast.LENGTH_SHORT);
toast.show();
}
});
Check if this calls your onCreate(...) method.
I'd also suggest you to add IF NOT EXISTS to your createTable Strings like so:"CREATE TABLE IF NOT EXISTS " + TABLE_USERS. This way, if you ever add a table, the others will not throw an error or be overwritten when the new table is created.
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/
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
I am new in Android development, And right now what I am trying to do is to save Message that I type and Username. I got this code from vogella.com, but it was written only for messages. And I have tried to add Username, but I get an error "java.lang.RuntimeException: Unable to start activity ComponentInfo{com.example.testdatabaseactivity/com.example.testdatabaseactivity.TestDatabaseActivity}: android.database.sqlite.SQLiteException: no such column: SENDER (code 1): , while compiling: SELECT _id, SENDER, MESSAGE FROM MESSAGES"
And I can't figure out what Is wrong. Need a little help.
MessagesDataSource.java
package com.example.testdatabaseactivity;
import java.util.ArrayList;
import java.util.List;
import android.content.ContentValues;
import android.content.Context;
import android.database.Cursor;
import android.database.SQLException;
import android.database.sqlite.SQLiteDatabase;
public class MessagesDataSource {
// Database fields
private SQLiteDatabase database;
private MySQLiteHelper dbHelper;
private String[] allColumns = { MySQLiteHelper.COLUMN_ID, MySQLiteHelper.COLUMN_SENDER, MySQLiteHelper.COLUMN_MESSAGE};
public MessagesDataSource(Context context) {
dbHelper = new MySQLiteHelper(context);
}
public void open() throws SQLException {
database = dbHelper.getWritableDatabase();
}
public void close() {
dbHelper.close();
}
public Message createMessage(String sender, String message) {
ContentValues values = new ContentValues();
values.put(MySQLiteHelper.COLUMN_MESSAGE, message);
values.put(MySQLiteHelper.COLUMN_SENDER, sender);
long insertId = database.insert(MySQLiteHelper.TABLE_MESSAGES, null,values);
Cursor cursor = database.query(MySQLiteHelper.TABLE_MESSAGES,allColumns, MySQLiteHelper.COLUMN_ID + " = " + insertId, null,null, null, null);
cursor.moveToFirst();
Message newMessage = cursorToMessage(cursor);
cursor.close();
return newMessage;
}
public List<Message> getAllMessages() {
List<Message> messages = new ArrayList<Message>();
Cursor cursor = database.query(MySQLiteHelper.TABLE_MESSAGES,allColumns, null, null, null, null, null);
cursor.moveToFirst();
while (!cursor.isAfterLast()) {
Message message = cursorToMessage(cursor);
messages.add(message);
cursor.moveToNext();
}
// make sure to close the cursor
cursor.close();
return messages;
}
private Message cursorToMessage(Cursor cursor) {
Message message = new Message();
message.setId(cursor.getLong(0));
message.setMessage(cursor.getString(2));
message.setSender(cursor.getString(1));
return message;
}
}
Message.java
package com.example.testdatabaseactivity;
public class Message {
private long id;
private String message;
private String sender;
public long getId() {
return id;
}
public void setId(long id) {
this.id = id;
}
public String getMessage() {
return message;
}
public void setMessage(String message) {
this.message = message;
}
public String getSender() {
return sender;
}
public void setSender(String sender) {
this.sender = sender;
}
// Will be used by the ArrayAdapter in the ListView
#Override
public String toString() {
return message;
}
}
MySQLiteHelper.java
package com.example.testdatabaseactivity;
import android.content.Context;
import android.database.sqlite.SQLiteDatabase;
import android.database.sqlite.SQLiteOpenHelper;
import android.util.Log;
public class MySQLiteHelper extends SQLiteOpenHelper {
public static final String TABLE_MESSAGES = "MESSAGES";
public static final String COLUMN_ID = "_id";
public static final String COLUMN_MESSAGE = "MESSAGE";
public static final String COLUMN_SENDER = "SENDER";
private static final String DATABASE_NAME = "message.db";
private static final int DATABASE_VERSION = 1;
// Database creation sql statement
private static final String DATABASE_CREATE = "create table " + TABLE_MESSAGES + "("
+ COLUMN_ID + " integer primary key autoincrement, "
+ COLUMN_SENDER + "sender not null, "
+ COLUMN_MESSAGE + " text not null);";
public MySQLiteHelper(Context context) {
super(context, DATABASE_NAME, null, DATABASE_VERSION);
}
#Override
public void onCreate(SQLiteDatabase database) {
database.execSQL(DATABASE_CREATE);
}
#Override
public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {
Log.w(MySQLiteHelper.class.getName(),"Upgrading database from version " + oldVersion + " to " + newVersion + ", which will destroy all old data");
db.execSQL("DROP TABLE IF EXISTS " + TABLE_MESSAGES);
onCreate(db);
}
}
TestDatabaseActivity.java
package com.example.testdatabaseactivity;
import java.util.List;
import android.app.ListActivity;
import android.os.Bundle;
import android.view.View;
import android.widget.ArrayAdapter;
import android.widget.EditText;
public class TestDatabaseActivity extends ListActivity {
private MessagesDataSource datasource;
public String sender = "Suren";
EditText edittext;
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
edittext = (EditText) findViewById(R.id.txt_message);
datasource = new MessagesDataSource(this);
datasource.open();
List<Message> values = datasource.getAllMessages();
// use the SimpleCursorAdapter to show the
// elements in a ListView
ArrayAdapter<Message> adapter = new ArrayAdapter<Message>(this,android.R.layout.simple_list_item_1, values);
setListAdapter(adapter);
}
// Will be called via the onClick attribute
// of the buttons in main.xml
public void onClick(View view) {
#SuppressWarnings("unchecked")
String text = edittext.getText().toString();
ArrayAdapter<Message> adapter = (ArrayAdapter<Message>) getListAdapter();
Message message = null;
if(edittext.length() == 0){
return;
}else{
// save the new message to the database
message = datasource.createMessage(sender, text);
adapter.add(message);
edittext.getText().clear();
}
adapter.notifyDataSetChanged();
}
#Override
protected void onResume() {
datasource.open();
super.onResume();
}
#Override
protected void onPause() {
datasource.close();
super.onPause();
}
}
Correct your CREATE Table Query need space between Column Name and Column Type
// Database creation sql statement
private static final String DATABASE_CREATE = "create table " + TABLE_MESSAGES + "("
+ COLUMN_ID + " integer primary key autoincrement, "
+ COLUMN_SENDER + " text not null, "
+ COLUMN_MESSAGE + " text not null);";
You Forget to add space over here in your Query COLUMN_SENDER + "sender not null, "
// Database creation sql statement
private static final String DATABASE_CREATE = "CREATE TABLE " + TABLE_MESSAGES + "("
+ COLUMN_ID + " INTEGER PRIMARY KEY AUTOINCREMENT, "
+ COLUMN_SENDER + " text not null, "
+ COLUMN_MESSAGE + " text not null)";
"sender" is not a type. You need put "text".
And give the appropriate spaces.