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no such table: reward (code 1): , while compiling: INSERT INTO reward(Reward2,Reward1,Reward3) VALUES (?,?,?)

Hello I'm a student and doing my final year project using sql and android studio. I want to create multiple table and I've trying to follow the example but it doesn't work. the error was no table created. Here my coding
DatabaseHelper.java
package com.example.multipletable;
import android.content.ContentValues;
import android.content.Context;
import android.database.sqlite.SQLiteDatabase;
import android.database.sqlite.SQLiteOpenHelper;
import android.util.Log;
import java.text.SimpleDateFormat;
import java.util.Date;
import java.util.Locale;
import androidx.annotation.Nullable;
import static android.content.ContentValues.TAG;
public class DatabaseHelper extends SQLiteOpenHelper {
private static final String DATABASE_NAME = "MultipleTable";
private static final int DATABASE_VERSION = 3;
private static final String TABLE_1 = "register";
private static final String TABLE_2 = "activity";
private static final String TABLE_3 = "reward";
String table_1 = "CREATE TABLE "+TABLE_1+" (matricno TEXT PRIMARY KEY, password TEXT, email TEXT)";
String table_2 = "CREATE TABLE "+TABLE_2+" (id INTEGER PRIMARY KEY AUTOINCREMENT, t_question TEXT, date DEFAULT CURRENT_DATE)";
String table_3 = "CREATE TABLE "+TABLE_3+" (_id INTEGER PRIMARY KEY AUTOINCREMENT, badge_green TEXT, badge_purple TEXT, badge_maroon TEXT)";
public DatabaseHelper(#Nullable Context context) {
super(context, DATABASE_NAME, null, DATABASE_VERSION);
}
#Override
public void onCreate(SQLiteDatabase db) {
db.execSQL(table_1);
}
#Override
public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {
Log.d(TAG, "Current version"+db.getVersion());
for (int version=oldVersion+1; version<=newVersion; version++) {
switch (version) {
case 2:
db.execSQL(table_2);
case 3:
db.execSQL(table_3);
}
}
// Log.e("DATABASE VERSION", db.getVersion()+" ");
//
// db.execSQL("DROP TABLE IF EXISTS "+TABLE_1);
// db.execSQL("DROP TABLE IF EXISTS "+TABLE_2);
// db.execSQL("DROP TABLE IF EXISTS "+TABLE_3);
//
// onCreate(db);
}
public boolean insert(String matNo, String pswd, String email) {
SQLiteDatabase db_1 = this.getWritableDatabase();
ContentValues contentValues1 = new ContentValues();
contentValues1.put("MatricNo", matNo);
contentValues1.put("Password", pswd);
contentValues1.put("Email", email);
db_1.insert(TABLE_1, null, contentValues1);
return true;
}
public boolean insert2(String question) {
SQLiteDatabase db_2 = this.getWritableDatabase();
ContentValues contentValues2 = new ContentValues();
contentValues2.put("Question", question);
contentValues2.put("Date", getDate());
db_2.insert(TABLE_2, null, contentValues2);
return true;
}
public boolean insert3(String green, String purple, String maroon) {
SQLiteDatabase db_3 = this.getWritableDatabase();
ContentValues contentValues3 = new ContentValues();
contentValues3.put("Reward1", green);
contentValues3.put("Reward2", purple);
contentValues3.put("Reward3", maroon);
db_3.insert(TABLE_3, null, contentValues3);
return true;
}
private String getDate() {
SimpleDateFormat dateFormat = new SimpleDateFormat(
"dd-MM-yyyy", Locale.getDefault());
Date date = new Date();
return dateFormat.format(date);
}
}
MainActiviti.java
package com.example.multipletable;
import androidx.appcompat.app.AppCompatActivity;
import android.content.Intent;
import android.os.Bundle;
import android.view.View;
import android.widget.Button;
import android.widget.EditText;
import android.widget.TextView;
import android.widget.Toast;
public class MainActivity extends AppCompatActivity {
EditText name, pswd, email;
Button btn_1;
DatabaseHelper db;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
name = findViewById(R.id.txt_name);
pswd = findViewById(R.id.txt_password);
email = findViewById(R.id.txt_email);
btn_1 = findViewById(R.id.btn_next_1);
db = new DatabaseHelper(this);
btn_1.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
String person = name.getText().toString();
String pass = pswd.getText().toString();
String mail = email.getText().toString();
Boolean insert = db.insert(person, pass, mail);
if (insert==true) {
Toast.makeText(getApplicationContext(), "Data 1 saved", Toast.LENGTH_SHORT).show();
Intent intent1 = new Intent(MainActivity.this, Activity2.class);
startActivity(intent1);
}
else {
Toast.makeText(getApplicationContext(), "Data 1 error", Toast.LENGTH_SHORT).show();
}
}
});
}
}
Activity2.java
package com.example.multipletable;
import androidx.appcompat.app.AppCompatActivity;
import android.content.Intent;
import android.os.Bundle;
import android.view.View;
import android.widget.Button;
import android.widget.EditText;
import android.widget.Toast;
public class Activity2 extends AppCompatActivity {
EditText question;
Button btn2;
DatabaseHelper db;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_2);
question = findViewById(R.id.txt_question);
btn2 = findViewById(R.id.btn_next_2);
db = new DatabaseHelper(this);
btn2.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
String ques = question.getText().toString();
Boolean insert2 = db.insert2(ques);
if (insert2==true) {
Toast.makeText(getApplicationContext(), "Data 2 saved", Toast.LENGTH_SHORT).show();
Intent intent2 = new Intent(Activity2.this, Activity3.class);
startActivity(intent2);
}
else {
Toast.makeText(getApplicationContext(), "Data 2 error", Toast.LENGTH_SHORT).show();
}
}
});
}
}
Activity3.java
package com.example.multipletable;
import androidx.appcompat.app.AppCompatActivity;
import android.content.Intent;
import android.os.Bundle;
import android.view.View;
import android.widget.Button;
import android.widget.EditText;
import android.widget.Toast;
public class Activity3 extends AppCompatActivity {
EditText green, purple, maroon;
Button btn3;
DatabaseHelper db;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_3);
green = findViewById(R.id.txt_green);
purple = findViewById(R.id.txt_purple);
maroon = findViewById(R.id.txt_maroon);
btn3 = findViewById(R.id.btn_next_3);
db = new DatabaseHelper(this);
btn3.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
String grn = green.getText().toString();
String ppl = purple.getText().toString();
String mrn = maroon.getText().toString();
Boolean insert3 = db.insert3(grn, ppl, mrn);
if (insert3==true) {
Toast.makeText(getApplicationContext(), "Data 3 saved", Toast.LENGTH_SHORT).show();
Intent intent3 = new Intent(Activity3.this, FINISH.class);
startActivity(intent3);
}
else {
Toast.makeText(getApplicationContext(), "Data 3 error", Toast.LENGTH_SHORT).show();
}
}
});
}
}
Can you please help me find the solution and tell me what is wrong :(

I am not sure where your error comes from but, I am assuming its on launch or when you insert the data.
I create my SQL table like below.
However, I did encounter a really annoying issue of if I change my table my app would crash as it would not find it. The fix was I needed to uninstall the app on my phone before uploading the application from android studio to my phone. Hope it helps
public class DatabaseHelper extends SQLiteOpenHelper {
public static final String DATABASE_NAME ="TESTING.db";
// Database Version
private static final int DATABASE_VERSION = 1;
public static final String TABLE_1 = "T1";
public static final String TABLE_2 = "T2";
public static final String TABLE_3 = "T3";
public static final String COL1 = "ID";
public static final String COL2 = "D1";
public static final String COL3 = "D2";
public static final String COL4 = "D3";
public static final String COL5 = "D4";
public static final String COL6 = "D5";
public static final String COL7 = "D6";
public static final String COL8 = "time";
public DatabaseHelper(Context context) {
super(context, DATABASE_NAME, null, DATABASE_VERSION);
}
#Override
public void onCreate(SQLiteDatabase db) {
// creating required tables
String Created_TABLE_1= "CREATE TABLE " + TABLE_1 + " (ID INTEGER PRIMARY KEY, " +
"D1 TEXT, D2 TEXT, D3, TEXT, D4 TEXT, D5 TEXT, D6 TEXT, TIME TEXT)";
String Created_TABLE_2= "CREATE TABLE " + TABLE_2 + " (ID INTEGER PRIMARY KEY, " +
"D1 TEXT, D2 TEXT, D3, TEXT, D4 TEXT, D5 TEXT, D6 TEXT, TIME TEXT)";
String Created_TABLE_3= "CREATE TABLE " + TABLE_3 + " (ID INTEGER PRIMARY KEY, " +
"D1 TEXT, D2 TEXT, D3, TEXT, D4 TEXT, D5 TEXT, D6 TEXT, TIME TEXT)";
db.execSQL(Created_TABLE_1);
db.execSQL(Created_TABLE_2);
db.execSQL(Created_TABLE_3);
}
Ps Stay safe all

Thank you Eugene Troyanskii, forpas and Thomas Morris. I've solved the problem. Supposed to be assign with correct name for column according to create table statement at inserting data code, but I write it different.
Again thanks guys!

How to Retrieve Multiple data when clicked on listview?

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.

Android Studio project

Hi i am doing an andorid studio project, when I am adding my data the application and then trying to view the data im getting an Error saying "Error, Nothing Found". I made up a SQLite Database and hope someone can help me find the error.
package ie.wit.andrew.drivingschool;
import android.content.ContentValues;
import android.content.Context;
import android.database.Cursor;
import android.database.sqlite.SQLiteDatabase;
import android.database.sqlite.SQLiteOpenHelper;
public class DatabaseHelper extends SQLiteOpenHelper {
public static final String DATABASE_NAME = "Driver.db";
public static final String TABLE_NAME = "driver_table";
public static final String COL_1 = "ID";
public static final String COL_2 = "NAME";
public static final String COL_3 = "DATE OF BIRTH";
public static final String COL_4 = "LOGBOOK NUMBER"; //Making up my
//database of the
//information I will
//be entering into my
//application
public static final String COL_5 = "LESSON NUMBER";
public DatabaseHelper(Context context) {
super(context, DATABASE_NAME, null, 1); //when this constructor is
//called your Database has been
//created
}
#Override
public void onCreate(SQLiteDatabase db) {
db.execSQL("create table " + TABLE_NAME + " (ID INTEGER PRIMARY KEY
AUTOINCREMENT,NAME TEXT,DATE OF BIRTH TEXT, LOGBOOK NUMBER TEXT, LESSON
NUMBER INTEGER)");
}
#Override
public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {
db.execSQL("DROP TABLE IF EXISTS "+TABLE_NAME);
onCreate(db);
}
public boolean insertData(String name, String dateofbirth, String
logbooknumber, String lessonnumber) {
SQLiteDatabase db = this.getWritableDatabase();
ContentValues contentValues = new ContentValues();
contentValues.put(COL_2,name);
contentValues.put(COL_3,dateofbirth);
contentValues.put(COL_4,logbooknumber);
contentValues.put(COL_5,lessonnumber);
long result = db.insert(TABLE_NAME,null,contentValues); //This method
//returns -1
if (result == -1)
return false;
else
return true;
}
public Cursor getAllData() {
SQLiteDatabase db = this.getWritableDatabase();
Cursor res = db.rawQuery("select * from "+ TABLE_NAME,null);
return res;
}
}
package ie.wit.andrew.drivingschool;
import android.database.Cursor;
import android.support.v7.app.AlertDialog;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.view.View;
import android.widget.Button;
import android.widget.EditText;
import android.widget.Toast;
public class DrivingSchool extends AppCompatActivity {
DatabaseHelper myDb;
EditText editName,editDateofBirth,editLogbookNumber,editLessonNumber;
Button btnAddData;
Button btnviewAll;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_driving_school);
myDb = new DatabaseHelper(this);
editName = (EditText)findViewById(R.id.editText_name);
editDateofBirth = (EditText)findViewById(R.id.editText_dateofbirth);
editLogbookNumber = (EditText)findViewById(R.id.editText_logbooknumber);
editLessonNumber = (EditText)findViewById(R.id.editText_lessonNumber);
btnAddData = (Button)findViewById(R.id.button_add);
btnviewAll = (Button)findViewById(R.id.button_viewAll);
AddData();
viewAll();
}
public void AddData() {
btnAddData.setOnClickListener(
new View.OnClickListener() {
#Override
public void onClick(View v) {
boolean isInserted =
myDb.insertData(editName.getText().toString(),
editDateofBirth.getText().toString(),
editLogbookNumber.getText().toString(),
editLessonNumber.getText().toString());
if(isInserted = true)
Toast.makeText(DrivingSchool.this,"Data
Inserted",Toast.LENGTH_LONG).show();
else
Toast.makeText(DrivingSchool.this,"Data not
Inserted", Toast.LENGTH_LONG).show();
}
}
);
}
public void viewAll() {
btnviewAll.setOnClickListener(
new View.OnClickListener() {
#Override
public void onClick(View v){
Cursor res = myDb.getAllData();
if(res.getCount() == 0) {
//Show Message
showMessage("Error", "Nothing found");
return;
}
StringBuffer buffer = new StringBuffer();
while(res.moveToNext()) {
buffer.append("ID : "+ res.getString(0)+"\n");
buffer.append("NAME : "+ res.getString(1)+"\n");
buffer.append("DATE OF BIRTH : "+
res.getString(2)+"\n");
buffer.append("LOGBOOK NUMBER : "+
res.getString(3)+"\n\n");;
}
//showdata
showMessage("Data",buffer.toString());
}
}
);
}
public void showMessage(String title,String Message){
AlertDialog.Builder builder = new AlertDialog.Builder(this);
builder.setCancelable(true);
builder.setTitle(title);
builder.setMessage(Message);
builder.show();
}
}

Try removing space from your column name's

you are providing wrong column name that's why your database is not creating, please check this link for complete guide for creating and using database in Android application
http://www.androidhive.info/2011/11/android-sqlite-database-tutorial/

SQLite Database issue in TextView

I've been working on an app where the main Activity leads to CalendarActivity, which has a button leading to another Activity where the user creates an event. Once the event is created, the user is taken back to CalendarActivity, and a previously empty TextView displays the event. The code I've used seems like it should work, and is near verbatim from an online tutorial. I researched the comments of the video and the video maker's blog, and many others seem to say it works fine. I've check over and over, and I believe that its grammatically correct, etc, but I can not get it to load the event into the TextView. Any pointers even would help. I would ask you keep it near basic english, I am just getting into programming and am using this app as a learning experience.
Thanks!
CalendarActivity:
package com.bm.sn.sbeta;
import android.content.Intent;
import android.database.Cursor;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.view.View;
import android.widget.Button;
import android.widget.CalendarView;
import android.widget.TextView;
import java.io.BufferedReader;
import java.io.File;
import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.io.IOException;
import java.io.InputStreamReader;
public class CalendarActivity extends AppCompatActivity {
CalendarView calendar;
Button createEvent;
public static String createEventDate;
DatabaseHelper db;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_calendar);
Cursor result = db.getAllData();
if (result.getCount() == 0) {
noEventToday();
}else{
TextView eventList = (TextView)findViewById(R.id.eventList);
StringBuffer stringBuffer = new StringBuffer();
while (result.moveToNext()) {
stringBuffer.append("eventDat : "+result.getString(0)+"\n");
stringBuffer.append("timeHour : "+result.getString(1)+"\n");
stringBuffer.append("timeMinue : "+result.getString(2)+"\n");
stringBuffer.append("event : "+result.getString(3)+"\n");
stringBuffer.append("location : "+result.getString(4)+"\n");
stringBuffer.append("crew : "+result.getString(5)+"\n\n");
eventList.setText(stringBuffer);
}
}
calendar = (CalendarView)findViewById(R.id.calendar);
calendar.setOnDateChangeListener(new CalendarView.OnDateChangeListener(){
#Override
public void onSelectedDayChange(CalendarView view, int year, int month, int dayOfMonth){
createEventDate = (month+"."+dayOfMonth+"."+year);
createEvent.setText("Create Event for "+createEventDate);
}
});
createEvent = (Button)findViewById(R.id.eventCreateButton);
createEvent.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
Intent toEventCreateActivity = new Intent(CalendarActivity.this, EventCreateActivity.class);
startActivity(toEventCreateActivity);
}
});
}
/*public void fillEventList (){
}
public void noEventToday(){
TextView eventList = (TextView)findViewById(R.id.eventList);
eventList.setText("Nothing scheduled for today.");
}*/
}
EventCreateActivity:
package com.bm.sn.sbeta;
import android.content.Intent;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.view.View;
import android.widget.Button;
import android.widget.EditText;
import android.widget.TextView;
import android.widget.TimePicker;
import android.widget.Toast;
public class EventCreateActivity extends AppCompatActivity {
DatabaseHelper db;
String textViewText = CalendarActivity.createEventDate;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_event_create);
db = new DatabaseHelper(this);
final TextView titleTextView = (TextView)findViewById(R.id.titleTextView);
titleTextView.setText("Create event for "+textViewText);
final TimePicker timePicker = (TimePicker)findViewById(R.id.timePicker);
final EditText entryEvent = (EditText)findViewById(R.id.entryEvent);
final EditText entryLocation = (EditText)findViewById(R.id.entryLocation);
final EditText entryCrew = (EditText)findViewById(R.id.entryCrew);
Button createEventButton = (Button)findViewById(R.id.saveEvent);
createEventButton.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
db.insertData(
titleTextView.toString(),
timePicker.getCurrentHour().toString(),
timePicker.getCurrentMinute().toString(),
entryEvent.getText().toString(),
entryLocation.getText().toString(),
entryCrew.getText().toString()
);
Toast.makeText(EventCreateActivity.this, "I'll keep that in mind.", Toast.LENGTH_LONG).show();
Intent toCalendarActivity = new Intent(EventCreateActivity.this, CalendarActivity.class);
startActivity(toCalendarActivity);
}
});
}
}
DatabaseHelper:
package com.bm.sn.sbeta;
import android.content.ContentValues;
import android.content.Context;
import android.database.Cursor;
import android.database.sqlite.SQLiteDatabase;
import android.database.sqlite.SQLiteOpenHelper;
public class DatabaseHelper extends SQLiteOpenHelper{
public static final String DATABASE_NAME = "SavitaCalendar.db";
public static final String TABLE_NAME = "CalendarEvents";
public static final String col_0 = "ID";
public static final String col_1 = "eventDate" ;
public static final String col_2 = "timeHour";
public static final String col_3 = "timeMinute";
public static final String col_4 = "event";
public static final String col_5 = "location";
public static final String col_6 = "crew";
public DatabaseHelper(Context context) {
super(context, DATABASE_NAME, null, 1);
}
#Override
public void onCreate(SQLiteDatabase db) {
db.execSQL("create table "+TABLE_NAME+ " (ID INTEGER PRIMARY KEY AUTOINCREMENT,EVENTDATE TEXT,TIMEHOUR TEXT,TIMEMINUTE TEXT, EVENT TEXT, LOCATION TEXT, CREW TEXT); ");
}
#Override
public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {
db.execSQL("DROP TABLE IF EXISTS "+TABLE_NAME);
onCreate(db);
}
public void insertData (String eventDate, String timeHour, String timeMinute, String event, String location, String crew){
SQLiteDatabase db = this.getWritableDatabase();
ContentValues contentValues = new ContentValues();
contentValues.put(col_1, eventDate);
contentValues.put(col_2, timeHour);
contentValues.put(col_3, timeMinute);
contentValues.put(col_4, event);
contentValues.put(col_5, location);
contentValues.put(col_6, crew);
db.insert(TABLE_NAME, null, contentValues);
db.close();
}
public Cursor getAllData(){
SQLiteDatabase db = this.getWritableDatabase();
Cursor result = db.rawQuery("select * from "+TABLE_NAME, null);
return result;
}
}

You're reading your data from the DB in onCreate().
onCreate() is called when the Activity is (re)created. It is not guaranteed that it will be called when you navigate back from EventCreateActivity.
Take a look at the docs on the Activity lifecycle.
As #nuccio pointed it out, you also seem to forgot to initialize your DatabaseHelper instance.
You should use a singleton pattern there, something like this:
private static DatabaseHelper instance;
private DatabaseHelper(Context context) {
super(context, DATABASE_NAME, null, 1);
}
public static DatabaseHelper getInstance(Context context) {
if (instance == null) {
instance = new DatabaseHelper(context.getApplicationContext());
}
return instance;
}
You could start EventCreateActivity using startActivityForResult(), and override onActivityResult() in CalendarActivity to update your TextView.
For example:
public class CalendarActivity extends AppCompatActivity {
private static final int REQUEST_CREATE_EVENT = 0;
CalendarView calendar;
Button createEvent;
public static String createEventDate;
TextView eventList;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_calendar);
eventList = (TextView) findViewById(R.id.eventList);
getEvents();
calendar = (CalendarView) findViewById(R.id.calendar);
calendar.setOnDateChangeListener(new CalendarView.OnDateChangeListener() {
#Override
public void onSelectedDayChange(CalendarView view, int year, int month, int dayOfMonth) {
createEventDate = (month + "." + dayOfMonth + "." + year);
createEvent.setText("Create Event for " + createEventDate);
}
});
createEvent = (Button) findViewById(R.id.eventCreateButton);
createEvent.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
Intent toEventCreateActivity = new Intent(CalendarActivity.this, EventCreateActivity.class);
startActivityForResult(toEventCreateActivity, REQUEST_CREATE_EVENT);
}
});
}
private void getEvents() {
// getting our DatabaseHelper instance
DatabaseHelper db = DatabaseHelper.getInstance(this);
Cursor result = db.getAllData();
if (result.getCount() == 0) {
noEventToday();
} else {
StringBuffer stringBuffer = new StringBuffer();
while (result.moveToNext()) {
stringBuffer.append("eventDat : " + result.getString(0) + "\n");
stringBuffer.append("timeHour : " + result.getString(1) + "\n");
stringBuffer.append("timeMinue : " + result.getString(2) + "\n");
stringBuffer.append("event : " + result.getString(3) + "\n");
stringBuffer.append("location : " + result.getString(4) + "\n");
stringBuffer.append("crew : " + result.getString(5) + "\n\n");
eventList.setText(stringBuffer);
}
}
}
#Override
protected void onActivityResult(int requestCode, int resultCode, Intent data) {
if(resultCode == RESULT_OK && requestCode == REQUEST_CREATE_EVENT) {
getEvents();
}
}
public void noEventToday(){
TextView eventList = (TextView)findViewById(R.id.eventList);
eventList.setText("Nothing scheduled for today.");
}
}
And in EventCreateActivity:
createEventButton.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
db.insertData(
titleTextView.toString(),
timePicker.getCurrentHour().toString(),
timePicker.getCurrentMinute().toString(),
entryEvent.getText().toString(),
entryLocation.getText().toString(),
entryCrew.getText().toString()
);
Toast.makeText(EventCreateActivity.this, "I'll keep that in mind.", Toast.LENGTH_LONG).show();
setResult(RESULT_OK);
finish();
}
});
An even better approach would be to pass your new event data in the Intent, so you don't have to read the DB when going back to CalendarActivity.
Or at least return the new row ID, so only one record needs to be queried.

You didn't instantiate your db properly in CalendarActivity.
add this
db = new DatabaseHelper(this);
Here is where to add this to the class:
package com.mac.training.calendaractivitysqlhelperthing;
imports ...
public class CalendarActivity extends AppCompatActivity {
CalendarView calendar;
Button createEvent;
public static String createEventDate;
DatabaseHelper db;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_calendar);
//ADD this line here
db = new DatabaseHelper(this);
Cursor result = db.getAllData();
if (result.getCount() == 0) {
//noEventToday();
}else{
//etc
That alone should work, but if not. Also update your Manifest as well with this:
activity android:name=".EventCreateActivity"
<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
package="com.mac.training.calendaractivitysqlhelperthing">
<application
android:allowBackup="true"
android:icon="#mipmap/ic_launcher"
android:label="#string/app_name"
android:supportsRtl="true"
android:theme="#style/AppTheme">
<activity android:name=".CalendarActivity">
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
</activity>
<activity android:name=".EventCreateActivity" />
</application>
</manifest>

Android displaying data in TextView from Database

I have created a simple android application which asks for the users details such as name, number, blood type and saves it in a database. This happens in edit texts on the editscreen the application is then suppose to display all the data in the Main Activity screen in a TextView. I have made the code so that it displays the text in the textview however when I switch the application off and back on again the text simply disappears and is no longer there, I am also trying to make the text stay in the edit text like
Name: Jim
But when I change screens, so for example If I go from MainActivity to EditScreen the text is no longer visible in the Edit Screen.
Edit Screen which has the edit texts
package com.example.androidsimpledbapp1;
import android.app.Activity;
import android.content.Intent;
import android.os.Bundle;
import android.view.View;
import android.widget.EditText;
import android.widget.TextView;
public class EditScreen extends Activity {
/*
* Code Issues:
* Data is not being persisted on screen
* Also the edit text data is not being persisted
* Database is not overwriting row in the DB e.g. GaryJamesJimmy instead of Overwriting
* Database needs to retrieve all other rows and display them in the TextView
* Will need to implement overwriting functionality on the DB for each row
* Is Data even persisting?
*/
EditText firstNameInput;
EditText bloodTypeInput;
EditText contacNameInput;
EditText phoneNumberInput;
EditText relationshipInput;
MyDBHandler dbHandler;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_edit_screen);
//Setting EditTexts
firstNameInput = (EditText) findViewById(R.id.inputname);
bloodTypeInput = (EditText) findViewById(R.id.inputblood);
contacNameInput = (EditText) findViewById(R.id.inputcontact);
phoneNumberInput = (EditText) findViewById(R.id.inputnum);
relationshipInput = (EditText) findViewById(R.id.inputraltion);
//Setting DbHandler object
dbHandler = new MyDBHandler(this, null, null, 1);
}
public void saveMe(View v){
/*
* Making a new object
* Object takes 5 parameters
*/
Details detail = new Details(firstNameInput.getText().toString(),
bloodTypeInput.getText().toString(),
contacNameInput.getText().toString(),
phoneNumberInput.getText().toString(),
relationshipInput.getText().toString());
dbHandler.addProduct(detail);
//Sending Text To Main Activity
String dbString = dbHandler.databaseToString();
Intent myIntent = new Intent(v.getContext(),MainActivity.class);
myIntent.putExtra("mytext",dbString);
startActivity(myIntent);
//End of Sending to Main Activity
//Settint the text in Edit Text
firstNameInput.setText(dbString);
}
public void clearBtnPressed(View v){
dbHandler.deleteProducts();
}
}
Main Activity - This is the screen with the textview where the text is suppose to be displayed
package com.example.androidsimpledbapp1;
import android.app.Activity;
import android.content.Intent;
import android.os.Bundle;
import android.view.View;
import android.widget.TextView;
public class MainActivity extends Activity {
TextView mTextView;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
//Grabs the TextView
mTextView = (TextView)findViewById(R.id.dbname);
mTextView.setText(getIntent().getStringExtra("mytext"));
}
//Changing Activity
public void editBtnPressed(View v){
Intent intent = new Intent(MainActivity.this, EditScreen.class);
startActivity(intent);
}
}
Database Class
package com.example.androidsimpledbapp1;
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 {
/*
* Class for Working with DB
*/
//Update each time DB structure changes e.g. adding new property
private static final int DATABASE_VERSION =1;
//DB Name
private static final String DATABASE_NAME = "details.db";
//Table name
public static final String TABLE_PRODUCTS = "products";
//DB Columns
public static final String COLUMN_ID = "_Id";
public static final String COLUMN_PERSONNAME = "firstName";
public static final String COLUMN_PERSONBLOOD = "bloodType";
public static final String COLUMN_PERSONCONTACT = "contactName";
public static final String COLUMN_PERSONNUMBER = "phoneNumber";
public static final String COLUMN_PERSONRELATION = "relationship";
//Constructor
/*
* Passing information to super class in SQL
* Context is background information
* name of db
* Database version
*/
public MyDBHandler(Context context, String name, SQLiteDatabase.CursorFactory factory, int version){
super(context, DATABASE_NAME, factory, DATABASE_VERSION);
}
/*
* What to do first time when you create DB
* Creates the table the very first time
* (non-Javadoc)
* #see android.database.sqlite.SQLiteOpenHelper#onCreate(android.database.sqlite.SQLiteDatabase)
* Remember to use Commas as shown below
*/
#Override
public void onCreate(SQLiteDatabase db){
String query = "CREATE TABLE "+ TABLE_PRODUCTS + "(" +
COLUMN_ID + " INTEGER PRIMARY KEY AUTOINCREMENT, "+
COLUMN_PERSONNAME + " TEXT, "+
COLUMN_PERSONBLOOD + " TEXT, "+
COLUMN_PERSONCONTACT + " TEXT, "+
COLUMN_PERSONNUMBER + " TEXT, " +
COLUMN_PERSONRELATION + " TEXT " +
");";
//Execute the query
db.execSQL(query);
}
/*
* If ever upgrading DB call this method
* (non-Javadoc)
* #see android.database.sqlite.SQLiteOpenHelper#onUpgrade(android.database.sqlite.SQLiteDatabase, int, int)
*/
#Override
public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion){
//Delete the current table
db.execSQL("DROP TABLE IF EXISTS" + TABLE_PRODUCTS);
//create new table
onCreate(db);
}
//Add new row to the database
public void addProduct(Details details){
//Built in class - set values for different columns
//Makes inserting rows quick and easy
ContentValues values = new ContentValues();
values.put(COLUMN_PERSONNAME, details.get_firstName());
values.put(COLUMN_PERSONBLOOD, details.get_bloodType());
values.put(COLUMN_PERSONCONTACT, details.get_contactName());
values.put(COLUMN_PERSONNUMBER, details.get_phoneNumber());
values.put(COLUMN_PERSONRELATION, details.get_relationship());
SQLiteDatabase db = getWritableDatabase();
db.insert(TABLE_PRODUCTS, null, values);
db.close();
}
/*Updating Rows in the Database
public void updateProducts(Details details){
ContentValues cv = new ContentValues();
SQLiteDatabase db = getWritableDatabase();
db.update(TABLE_PRODUCTS, cv, COLUMN_ID + "=" + 1, null);
}
*/
/*Table was deleted*/
public void deleteProducts(){
SQLiteDatabase db = getWritableDatabase();
db.delete(TABLE_PRODUCTS, null, null);
}
//Take DB and Convert to String
public String databaseToString(){
String dbString = "";
SQLiteDatabase db = getWritableDatabase();
//Every Column and row
String query = "SELECT * FROM " + TABLE_PRODUCTS + " WHERE 1";
//Cursor points to a location in your results
//First row point here, second row point here
Cursor c = db.rawQuery(query, null);
c.moveToFirst();
while(!c.isAfterLast()){
//Extracts first name and adds to string
if(c.getString(c.getColumnIndex("firstName"))!=null){
dbString += c.getString(c.getColumnIndex("firstName"));
c.moveToNext();
/*
* Displaying all other columns
*/
}
}
db.close();
return dbString;
}
}
Details Class
package com.example.androidsimpledbapp1;
public class Details {
//primary key
private int _id;
//Properties
private String _firstName;
private String _bloodType;
private String _contactName;
private String _phoneNumber;
private String _relationship;
//Dont Have to Enter Everything each time
public Details(){
}
public Details(String firstName){
this.set_firstName(firstName);
}
//Passing in details
//Setting values from the user
public Details(String firstName, String bloodType,
String contactName, String phoneNumber,
String relationship){
this.set_firstName(firstName);
this.set_bloodType(bloodType);
this.set_contactName(contactName);
this.set_phoneNumber(phoneNumber);
this.set_relationship(relationship);
}
//Retrieve the data
public int get_id() {
return _id;
}
//Setter allows to give property
public void set_id(int _id) {
this._id = _id;
}
public String get_firstName() {
return _firstName;
}
public void set_firstName(String _firstName) {
this._firstName = _firstName;
}
public String get_bloodType() {
return _bloodType;
}
public void set_bloodType(String _bloodType) {
this._bloodType = _bloodType;
}
public String get_contactName() {
return _contactName;
}
public void set_contactName(String _contactName) {
this._contactName = _contactName;
}
public String get_phoneNumber() {
return _phoneNumber;
}
public void set_phoneNumber(String _phoneNumber) {
this._phoneNumber = _phoneNumber;
}
public String get_relationship() {
return _relationship;
}
public void set_relationship(String _relationship) {
this._relationship = _relationship;
}
}

When you switch your app, it's on pause state which may be the cause of your problem.
I suggest you search for "saving activity when onPause state"