I have 3 classes: MainActivity, DBHelper (extended SQLiteOpenHelper) and Student class.
In DBHelper I have methods like: addNewStudent, deleteStudent, findStudent and getAllStudents.
The method "getAllStudents" return arrayList and I want to show elements of this one in the listView on the mainactivity layou but I have problem with parameter of the ArrayList.
I tried on String just to understand using ArrayAdapter:
MAIN ACTIVITY
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
buttonAdd = (Button) findViewById(R.id.buttonAdd);
editTextID = (EditText) findViewById(R.id.editTextID);
editTextName = (EditText) findViewById(R.id.editTextName);
listViewStudents = (ListView) findViewById(R.id.listViewStudents);
mDBStudents = new DBhelper(this);
// ------> this one provisional works:
final ArrayList<String> namesArray = new ArrayList<String>();
namesArray.add("Hania");
namesArray.add("Kasia");
final ArrayAdapter<String> namesAdapter = new ArrayAdapter<String>(MainActivity.this,android.R.layout.simple_list_item_1,namesArray);
buttonAdd.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
namesArray.add(editTextName.getText().toString());
mDBStudents.addNewStudent(editTextName.getText().toString());
listViewStudents.setAdapter(namesAdapter);
// ------> this one using <object> parameter in the ArrayList doesn't work and my app is stopped. I tried with Log.d but how to do it correctly with objects...
final ArrayList<Student> studentArray = new ArrayList<Student>();
Student s1 = new Student(1, "Natalia");
studentArray.add(s1);
final ArrayAdapter<Student> studentAdapter = new ArrayAdapter<Student>(MainActivity.this, android.R.layout.simple_list_item_1, studentArray);
buttonAdd.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
Student s2 = new Student(Integer.parseInt(editTextID.getText().toString()), editTextName.getText().toString());
studentArray.add(s2);
mDBStudents.addNewStudent(editTextName.getText().toString());
listViewStudents.setAdapter(studentAdapter);
I want to show elements from the ArrayList which I add when I click "addStudentButton" in the ListView. Later I want t open the new Intent when I click on one positon from the listView. Do you have any suggestions what is the best way for beginner user of android?
On some pages are info about using ArrayAdapter, Cursor etc. but they aren't so clarity for me
DBhelper class
public class DBhelper extends SQLiteOpenHelper {
private static final int DATABASE_VERSION = 1;
private static final String DATABASE_NAME = "studentDB.db";
public static final String TABLE_NAME = "student";
public static final String COLUMN_ID = "studentID";
public static final String COLUMN_NAME = "studentName";
//initialize the database
public DBhelper(Context context) {
super(context, DATABASE_NAME, null, DATABASE_VERSION);
}
#Override
public void onCreate(SQLiteDatabase db) {
db.execSQL("CREATE TABLE " + TABLE_NAME + "("
+ COLUMN_ID + " INTEGER PRIMARY KEY,"
+ COLUMN_NAME + " TEXT " + ")");
}
#Override
public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {
db.execSQL("DROP TABLE IF EXISTS contacts");
onCreate(db);
}
public int addNewStudent(String studentName) {
SQLiteDatabase db = this.getWritableDatabase();
ContentValues values = new ContentValues();
values.put(COLUMN_NAME,studentName);
return (int) db.insert(TABLE_NAME,null, values); //???
}
public ArrayList<Student> getAllStudents() {
ArrayList<Student> result = new ArrayList<>();
SQLiteDatabase db = this.getWritableDatabase();
Cursor csr = db.query(TABLE_NAME,null,null,null,null,null,null);
while (csr.moveToNext()) {
result.add(
new Student(
csr.getInt(csr.getColumnIndex(COLUMN_ID)),
csr.getString(csr.getColumnIndex(COLUMN_NAME)
)
)
);
}
csr.close();
db.close();
return result;
}
public Student findStudent(int studentID) {
Student result = null;
String whereclause = COLUMN_ID + "=?";
String[] whereargs = new String[]{String.valueOf(studentID)};
SQLiteDatabase db = this.getWritableDatabase();
Cursor csr = db.query(TABLE_NAME,null,whereclause,whereargs,null,null,null);
if (csr.moveToFirst()) {
result = new Student(
csr.getInt(csr.getColumnIndex(COLUMN_ID)),
csr.getString(csr.getColumnIndex(COLUMN_NAME)
)
);
}
csr.close();
db.close();
return result;
}
public Student deleteStudent(int studentID) {
Student result = null;
String whereclause = COLUMN_ID + "=?";
String[] whereargs = new String[]{String.valueOf(studentID)};
SQLiteDatabase db = this.getWritableDatabase();
Cursor csr = db.query(TABLE_NAME, null, whereclause, whereargs, null, null, null);
if (csr.moveToFirst()) {
result = new Student(
csr.getInt(csr.getColumnIndex(COLUMN_ID)), csr.getString(csr.getColumnIndex(COLUMN_NAME)));
db.delete(TABLE_NAME, whereclause, whereargs);
}
csr.close();
db.close();
return result;
}
public boolean updateStudent(int studentID, String studentName) {
SQLiteDatabase db = this.getWritableDatabase();
ContentValues args = new ContentValues();
args.put(COLUMN_ID, studentID);
args.put(COLUMN_NAME, studentName);
return db.update(TABLE_NAME, args, COLUMN_ID + "=" + ID, null) > 0;
}
}
Student class
public class Student {
private int studentID;
private String studentName;
public Student(int id, String studentName) { //konstruktor
this.studentID = id;
this.studentName = studentName;
}
public int getStudentID() {
return studentID;
}
public void setStudentID(int studentID) {
this.studentID = studentID;
}
public String getStudentName() {
return studentName;
}
public void setStudentName(String studentName) {
this.studentName = studentName;
}
}
Related
Code
public class SettingsContacts extends AppCompatActivity {
private RecyclerView contactsList;
private List<ContactsHelper> contacts = new ArrayList<>();
private LinearLayoutManager linearLayoutManager;
private ContactsAdapter mAdapter;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_settings_contacts);
contactsList = (RecyclerView) findViewById(R.id.usersList);
//Add the data first
addDataToList();
linearLayoutManager = new LinearLayoutManager(getApplicationContext());
//and then create a object and pass the lis
mAdapter = new ContactsAdapter(contacts);
contactsList.setHasFixedSize(true);
contactsList.setLayoutManager(linearLayoutManager);
contactsList.setAdapter(mAdapter);
mAdapter.notifyDataSetChanged();
}
public void addDataToList() {
ContentResolver contentResolver = getContentResolver();
Cursor cursor = contentResolver.query(ContactsContract.Contacts.CONTENT_URI, null, null, null, ContactsContract.CommonDataKinds.Phone.DISPLAY_NAME + " ASC");
if (cursor != null) {
if (cursor.getCount() > 0) {
while (cursor.moveToNext()) {
int hasPhoneNumber = Integer.parseInt(cursor.getString(cursor.getColumnIndex(ContactsContract.Contacts.HAS_PHONE_NUMBER)));
if (hasPhoneNumber > 0) {
String id = cursor.getString(cursor.getColumnIndex(ContactsContract.Contacts._ID));
String name = cursor.getString(cursor.getColumnIndex(ContactsContract.Contacts.DISPLAY_NAME));
Cursor phoneCursor = contentResolver.query(
ContactsContract.CommonDataKinds.Phone.CONTENT_URI,
null,
ContactsContract.CommonDataKinds.Phone.CONTACT_ID + " = ?", new String[]{id},
null);
if (phoneCursor != null) {
if (phoneCursor.moveToNext()) {
String phoneNumber = phoneCursor.getString(phoneCursor.getColumnIndex(ContactsContract.CommonDataKinds.Phone.NUMBER));
contacts.add(new ContactsHelper(name, phoneNumber));
phoneCursor.close();
}
}
}
}
}
cursor.close();
}
}
}
This displays all the contacts in the users phone in an activity... How do i move the data into a table in SQLite?
Progress so far:
public class DatabaseHelper extends SQLiteOpenHelper {
// Table Name
public static final String TABLE_NAME = "Contacts";
// Table columns
public static final String ID = "ID";
public static final String Contact_Name = "Contact_Name";
public static final String Phone_Number = "Phone_Number";
// Database Information
static final String DB_NAME = "MessagePlus_Contacts";
// database version
static final int DB_VERSION = 1;
// Creating table query
private static final String CREATE_TABLE = "Create Table " + TABLE_NAME + "(" + ID
+ " INTEGER PRIMARY KEY AUTOINCREMENT, " + Contact_Name + " TEXT NOT NULL, " + Phone_Number + " INT NOT NULL);";
public DatabaseHelper(Context context) {
super(context, DB_NAME, null, DB_VERSION);
}
#Override
public void onCreate(SQLiteDatabase db) {
db.execSQL(CREATE_TABLE);
}
#Override
public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {
db.execSQL("DROP TABLE IF EXISTS " + TABLE_NAME);
onCreate(db);
}
Helper
public class ContactsHelper {
private String Name;
private String PhoneNumber;
public ContactsHelper() {
}
public ContactsHelper(String Name, String PhoneNumber) {
this.Name = Name;
this.PhoneNumber = PhoneNumber;
}
public String getName() {
return Name;
}
public void setName(String Name) {
this.Name = Name;
}
public String getPhoneNumber() {
return PhoneNumber;
}
public void setPhoneNumber(String PhoneNumber) {
this.PhoneNumber = PhoneNumber;
}
}
I've got to this point but I don't know how to proceed because I have so far only worked with adding/modifying data by clicking a button or similar to that.
How do I move the complete data to SQLite and when new contact is added obviously it wont get added to table automatically so when I add a feature like swipe to refresh I want the new contact to be added to the data as well?
Solution:
Add this method in your DatabaseHelper class:
public void insertData(String contactName, String phoneNumber) {
SQLiteDatabase db = this.getWritableDatabase();
ContentValues values = new ContentValues();
values.put(DatabaseHelper.Contact_Name, contactName);
values.put(DatabaseHelper.Phone_Number, phoneNumber);
db.insert(DatabaseHelper.TABLE_NAME, null, values);
// close db connection
db.close();
}
then, Firstly, make DatabaseHelper global object in your SettingsContacts class:
public DatabaseHelper database;
Add this in youronCreate()
database = new DatabaseHelper(SettingsContacts.this);
then after this, add the below line in addDataToList() method as shown:
Add this line:
database.insertData(name, phoneNumber)
as shown in below code (Write Here):
if (phoneCursor != null) {
if (phoneCursor.moveToNext()) {
String phoneNumber = phoneCursor.getString(phoneCursor.getColumnIndex(ContactsContract.CommonDataKinds.Phone.NUMBER));
contacts.add(new ContactsHelper(name, phoneNumber));
phoneCursor.close();
....... (Write Here)
}
}
That's it.
Hope it works.
To see if the data is already inserted, you can check the count of your table:
public int getCount() {
String countQuery = "SELECT * FROM " + DatabaseHandler.TABLE_NAME;
SQLiteDatabase db = this.getReadableDatabase();
Cursor cursor = db.rawQuery(countQuery, null);
int count = cursor.getCount();
cursor.close();
// return count
return count;
}
Write the above method in you Database Handler class.
Then, in your activity after calling insertData(..), you can write like:
int count = database.getCount();
Log.e("Count From DB: ", String.valueOf(count));
I have made a local database.I have accessing it using diffrent methods but i think CursorLoader is the efficient way to access it.But i don't know know how to do it.Can anyone help?Here is my code
Main Activity
public class Main2Activity extends AppCompatActivity implements
LoaderManager.LoaderCallbacks<Cursor>{
TextView t1;
RecyclerView mRecyclerView;
RecyclerAdapter recyclerAdapter;
RecyclerAdapter adapter;
List<Info> infoList;
String arrr;
int ar;
int Loader_id=1;
private RecyclerView.LayoutManager mLayoutManager;
SimpleCursorAdapter simpleCursorAdapter;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main2);
final DatabaseHandler db = new DatabaseHandler(this);
List<Info> infos = db.getAllInfo();
mRecyclerView = (RecyclerView) findViewById(R.id.recycler_view);
mLayoutManager = new LinearLayoutManager(this);
mRecyclerView.setLayoutManager(mLayoutManager);
mRecyclerView.addItemDecoration(new SimpleDivider(Main2Activity.this));
recyclerAdapter = new RecyclerAdapter(this, infos);
mRecyclerView.setAdapter(recyclerAdapter);
}
#Override
public Loader<Cursor> onCreateLoader(int id, Bundle args) {
return null;
}
#Override
public void onLoadFinished(Loader<Cursor> loader, Cursor data) {
}
#Override
public void onLoaderReset(Loader<Cursor> loader) {
}
}
DataBaseHandler
public class DatabaseHandler extends SQLiteOpenHelper {
private static final int DATABASE_VERSION = 1;
private static final String DATABASE_NAME = "Dispalymanager";
private static final String TABLE = "contacts";
private static final String KEY_ID = "id";
private static final String KEY_NAME = "name";
private static final String KEY_AGE = "age";
public DatabaseHandler(Context context) {
super(context, DATABASE_NAME, null, DATABASE_VERSION);
}
#Override
public void onCreate(SQLiteDatabase db) {
String CREATE_TABLE = "CREATE TABLE " + TABLE + "(" + KEY_ID + " INTEGER PRIMARY KEY," + KEY_NAME + " TEXT," + KEY_AGE + " TEXT" + ")";
db.execSQL(CREATE_TABLE);
}
#Override
public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {
db.execSQL("DROP TABLE IF EXISTS " + TABLE);
onCreate(db);
}
void addInfo(Info info) {
SQLiteDatabase db = this.getWritableDatabase();
ContentValues values = new ContentValues();
values.put(KEY_NAME, info.getName());
values.put(KEY_AGE, info.getAge());
db.insert(TABLE, null, values);
db.close();
}
Info getinfo(int id) {
SQLiteDatabase db = this.getReadableDatabase();
Cursor cursor = db.query(TABLE, new String[]{KEY_ID, KEY_NAME, KEY_AGE}, KEY_ID + "=?",
new String[]{String.valueOf(id)}, null, null, null, null);
if (cursor != null)
cursor.moveToFirst();
Info info = new Info(Integer.parseInt(cursor.getString(0)),
cursor.getString(1), cursor.getString(2));
return info;
}
public List<Info> getAllInfo() {
List<Info> infoList = new ArrayList<Info>();
String selectQuery = "SELECT * FROM " + TABLE;
SQLiteDatabase db = this.getWritableDatabase();
Cursor cursor = db.rawQuery(selectQuery, null);
if (cursor.moveToFirst()) {
do {
Info contact = new Info();
contact.setID(Integer.parseInt(cursor.getString(0)));
contact.setName(cursor.getString(1));
contact.setPhoneNumber(cursor.getString(2));
infoList.add(contact);
} while (cursor.moveToNext());
}
return infoList;
}
public int updateInfo(Info info) {
SQLiteDatabase db = this.getWritableDatabase();
ContentValues values = new ContentValues();
values.put(KEY_NAME, info.getName());
values.put(KEY_AGE, info.getAge());
return db.update(TABLE, values, KEY_ID + " = ?", new String[]{String.valueOf(info.getID())});
}
public void deleteInfo(Info contact) {
SQLiteDatabase db = this.getWritableDatabase();
db.delete(TABLE, KEY_NAME + " = ?", new String[]{String.valueOf(contact.getName())});
db.close();
}
public int getInfoCount() {
String countQuery = "SELECT * FROM " + TABLE;
SQLiteDatabase db = this.getReadableDatabase();
Cursor cursor = db.rawQuery(countQuery, null);
int count = cursor.getCount();
cursor.close();
return count;
}
boolean deleteitem(int id){
SQLiteDatabase db = this.getWritableDatabase();
db.execSQL("delete from "+TABLE+" where "+KEY_ID+" ="+id);
return true;
}
}
I'm trying to figure a way of allowing users NOT to be able to add the same ID twice as if I wanted to delete one of the users and he shared the ID with another it would delete both.
So far I have found no help doing so does anyone have an idea?
public class MainActivity extends AppCompatActivity {
private Button button;
private EditText IdText;
private EditText NameText;
private EditText AgeText;
private EditText WeightText;
private EditText HeightText;
private EditText ReachText;
MyDBHandler dbHandler;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
IdText = (EditText) findViewById(R.id.IdText);
NameText = (EditText) findViewById(R.id.NameText);
HeightText = (EditText) findViewById(R.id.HeightText);
AgeText = (EditText) findViewById(R.id.AgeText);
WeightText = (EditText) findViewById(R.id.WeightText);
ReachText = (EditText) findViewById(R.id.ReachText);
button = (Button) findViewById(R.id.button);
dbHandler = new MyDBHandler(this);
AddData();
}
public void AddData() {
button.setOnClickListener(
new View.OnClickListener() {
#Override
public void onClick(View v) {
if ((IdText.getText().toString()).isEmpty()) {
IdText.setError("Please fill out your name");
return;
} else if ((NameText.getText().toString()).isEmpty()) {
NameText.setError("Please fill out your ID");
return;
} else if ((AgeText.getText().toString()).isEmpty()) {
AgeText.setError("Please fill out your Age");
return;
} else if ((HeightText.getText().toString()).isEmpty()) {
HeightText.setError("Please fill out your Height in centimeters");
return;
} else if ((WeightText.getText().toString()).isEmpty()) {
WeightText.setError("Please fill out your weight in kilos");
return;
} else if ((ReachText.getText().toString()).isEmpty()) {
ReachText.setError("Please fill out your reach in inches");
return;
} else {
boolean isInserted = dbHandler.insertData(IdText.getText().toString(),
NameText.getText().toString(),
AgeText.getText().toString(),
HeightText.getText().toString(),
WeightText.getText().toString(),
ReachText.getText().toString());
if (isInserted == true)
Toast.makeText(MainActivity.this, "Fighter added", Toast.LENGTH_LONG).show();
else
Toast.makeText(MainActivity.this, "Data not inserted", Toast.LENGTH_LONG).show();
}
}
}
);
}
public class MyDBHandler extends SQLiteOpenHelper {
private static final int DATABASE_VERSION = 1;
private static final String DATABASE_NAME = "Fighters.db";
public static final String TABLE_PRODUCTS = "Fighter";
public static final String COLUMN_ID = "ID1";
public static final String COLUMN_NAME = "Name";
public static final String COLUMN_AGE = "Age";
public static final String COLUMN_WEIGHT = "Weight";
public static final String COLUMN_HEIGHT = "Height";
public static final String COLUMN_REACH = "Reach";
SQLiteDatabase db;
public MyDBHandler(Context context) {
super(context, DATABASE_NAME, null, 1);
SQLiteDatabase db = this.getWritableDatabase();
}
#Override
public void onCreate(SQLiteDatabase db) {
db.execSQL("CREATE TABLE " + TABLE_PRODUCTS + " (ID INTEGER PRIMARY KEY AUTOINCREMENT,ID1 TEXT,Name TEXT,Age INTEGER,Weight INTEGER,Height TEXT,Reach TEXT)");
}
#Override
public void onUpgrade(SQLiteDatabase db, int i, int i1) {
db.execSQL("DROP TABLE IF EXISTS" + TABLE_PRODUCTS);
this.onCreate(db);
}
//Add new row to the database
public boolean insertData(String id1, String name, String age, String weight, String height, String reach) {
SQLiteDatabase db = this.getWritableDatabase();
ContentValues contentValues = new ContentValues();
contentValues.put(COLUMN_ID, id1);
contentValues.put(COLUMN_NAME, name);
contentValues.put(COLUMN_AGE, age);
contentValues.put(COLUMN_WEIGHT, weight);
contentValues.put(COLUMN_HEIGHT, height);
contentValues.put(COLUMN_REACH, reach);
long result = db.insert(TABLE_PRODUCTS, null, contentValues);
if (result == -1)
return false;
else
return true;
}
public Cursor getAllData() {
SQLiteDatabase db = this.getWritableDatabase();
Cursor res = db.rawQuery("select * from " + TABLE_PRODUCTS, null);
return res;
}
public boolean updateData(String id1,String name, String age, String weight, String height, String reach) {
SQLiteDatabase db = this.getWritableDatabase();
ContentValues contentValues = new ContentValues();
contentValues.put(COLUMN_ID, id1);
contentValues.put(COLUMN_NAME, name);
contentValues.put(COLUMN_AGE, age);
contentValues.put(COLUMN_WEIGHT, weight);
contentValues.put(COLUMN_HEIGHT, height);
contentValues.put(COLUMN_REACH, reach);
db.update(TABLE_PRODUCTS, contentValues, "ID1 = ?", new String[] {id1 });
return true;
}
public Integer deleteData (String id) {
SQLiteDatabase db = this.getWritableDatabase();
return db.delete(TABLE_PRODUCTS, "ID1 = ?", new String[] {id});
}
i need to make custom layout for my list view where data source is a sqlite database
when i run this code my output Thus shows (name next to phone) but i need to display output like this (phone under
name)
this is my code
here public class MainActivity extends AppCompatActivity {
AlertDialog.Builder builder;
List<Todo> todos;
MyDataBase db = new MyDataBase(this);
String m,m1;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
final EditText editText = (EditText) findViewById(R.id.editText);
final EditText editText1 = (EditText) findViewById(R.id.editText2);
Button button = (Button) findViewById(R.id.button);
ListView listView = (ListView) findViewById(R.id.listView);
todos = db.getallcontacts();
final ArrayAdapter adapter = new ArrayAdapter(this,R.layout.support_simple_spinner_dropdown_item,todos);
button.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
m = editText.getText().toString();
m1 = editText1.getText().toString();
db.AddnewContact(new Todo(m, m1));
adapter.add(new Todo(m, m1));
Toast.makeText(getApplicationContext(), "contact saved", Toast.LENGTH_LONG).show();
}
});
listView.setOnItemClickListener(new OnItemClickListener() {
#Override
public void onItemClick(AdapterView<?> parent, View view,
final int position, long rowId) {
AlertDialog.Builder adb = new AlertDialog.Builder(
MainActivity.this);
adb.setMessage("you need to delete this contact");
adb.setPositiveButton("delete", new DialogInterface.OnClickListener() {
#Override
public void onClick(DialogInterface dialog, int which) {
Todo td = todos.get(position);
db.deleteContact(td);
adapter.remove(td);
}
});
adb.show();
adapter.notifyDataSetChanged();
}
});
listView.setAdapter(adapter);
}
my database calss
here public class MyDataBase extends SQLiteOpenHelper {
private static final int DATABASE_VERSION = 1;
// Database Name
private static final String DATABASE_NAME = "contactsManager";
// Contacts table name
private static final String TABLE_CONTACTS = "contacts";
// Contacts Table Columns names
private static final String KEY_ID = "id";
final String KEY_NAME = "name";
final String KEY_PH_NO = "phone_number";
public MyDataBase(Context context) {
super(context, DATABASE_NAME, null, DATABASE_VERSION);
}
#Override
public void onCreate(SQLiteDatabase db) {
String CREATE_CONTACTS_TABLE = "CREATE TABLE " + TABLE_CONTACTS + "("
+ KEY_ID + " INTEGER PRIMARY KEY," + KEY_NAME + " TEXT,"
+ KEY_PH_NO + " TEXT" + ")";
db.execSQL(CREATE_CONTACTS_TABLE);
}
#Override
public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {
}
public void AddnewContact (Todo todo)// this method to add new contact
{
SQLiteDatabase db = this.getWritableDatabase();
ContentValues values = new ContentValues();
values.put(KEY_NAME,todo.getName());
values.put(KEY_PH_NO, todo.getPhoneNumber());
db.insert(TABLE_CONTACTS, null, values);
db.close();
}
public Todo getContact(int id)
{
SQLiteDatabase db = this.getReadableDatabase();
Cursor cursor = db.query(TABLE_CONTACTS,new String[] { KEY_ID,
KEY_NAME, KEY_PH_NO },KEY_ID + "=?",new String[] { String.valueOf(id) },null,null,null,null);
cursor.moveToFirst();
Todo contact = new Todo(Integer.parseInt(cursor.getString(0)),
cursor.getString(1), cursor.getString(2));
// return contact
return contact;
}
public List<Todo> getallcontacts()
{
List<Todo> contactList = new ArrayList<Todo>();
String selectQuery = "SELECT * FROM " + TABLE_CONTACTS;
SQLiteDatabase db = this.getWritableDatabase();
Cursor cursor = db.rawQuery(selectQuery, null);
if (cursor.moveToFirst()) {
do {
Todo contact = new Todo();
contact.setID(Integer.parseInt(cursor.getString(0)));
contact.setName(cursor.getString(1));
contact.setPhoneNumber(cursor.getString(2));
// Adding contact to list
contactList.add(contact);
} while (cursor.moveToNext());
}
// return contact list
return contactList;
}
public void deleteContact(Todo contact) {
int id = contact.getID();
SQLiteDatabase db = this.getWritableDatabase();
db.delete(TABLE_CONTACTS, KEY_ID
+ " = " + id, null);
db.close();
}
public Cursor fetchAllCountries() {
SQLiteDatabase database = this.getWritableDatabase();
Cursor mCursor = database.query(TABLE_CONTACTS, new String[] {KEY_ID,
KEY_NAME,KEY_PH_NO},
null, null, null, null, null);
if (mCursor != null) {
mCursor.moveToFirst();
}
return mCursor;
}
}
my todo calss
`enter public class Todo {
//private variables
int _id;
String _name;
String _phone_number;
// Empty constructor
public Todo(){
}
// constructor
public Todo(int id, String name, String _phone_number){
this._id = id;
this._name = name;
this._phone_number = _phone_number;
}
// constructor
public Todo(String name, String _phone_number){
this._name = name;
this._phone_number = _phone_number;
}
// getting ID
public int getID(){
return this._id;
}
// setting id
public void setID(int id){
this._id = id;
}
// getting name
public String getName(){
return this._name;
}
// setting name
public void setName(String name){
this._name = name;
}
// getting phone number
public String getPhoneNumber(){
return this._phone_number;
}
// setting phone number
public void setPhoneNumber(String phone_number){
this._phone_number = phone_number;
}
#Override
public String toString() {
return _name+" "+_phone_number;
}
}
`
This question already has answers here:
Unfortunately MyApp has stopped. How can I solve this?
(23 answers)
Closed 7 years ago.
the database class
public class DBHelper extends SQLiteOpenHelper {
public static final String DATABASE_NAME = "MyDBName.db";
public static final String CONTACTS_TABLE_NAME = "contacts";
public static final String CONTACTS_COLUMN_ID = "id";
public static final String CONTACTS_COLUMN_NAME = "name";
public static final String CONTACTS_COLUMN_EMAIL = "email";
public static final String CONTACTS_COLUMN_STREET = "street";
public static final String CONTACTS_COLUMN_CITY = "place";
public static final String CONTACTS_COLUMN_PHONE = "phone";
private HashMap hp;
public DBHelper(Context context)
{
super(context, DATABASE_NAME , null, 1);
}
#Override
public void onCreate(SQLiteDatabase db) {
// TODO Auto-generated method stub
db.execSQL(
"create table contacts " +
"(id integer primary key, name text,phone text,email text, street text,place text)"
);
}
#Override
public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {
// TODO Auto-generated method stub
db.execSQL("DROP TABLE IF EXISTS contacts");
onCreate(db);
}
public boolean insertContact (String name, String phone, String email, String street,String place)
{
SQLiteDatabase db = this.getWritableDatabase();
ContentValues contentValues = new ContentValues();
contentValues.put("name", name);
contentValues.put("phone", phone);
contentValues.put("email", email);
contentValues.put("street", street);
contentValues.put("place", place);
db.insert("contacts", null, contentValues);
return true;
}
public Cursor getData(int id){
SQLiteDatabase db = this.getReadableDatabase();
Cursor res = db.rawQuery( "select * from contacts where id="+id+"", null );
return res;
}
public int numberOfRows(){
SQLiteDatabase db = this.getReadableDatabase();
int numRows = (int) DatabaseUtils.queryNumEntries(db, CONTACTS_TABLE_NAME);
return numRows;
}
public boolean updateContact (Integer id, String name, String phone, String email, String street,String place)
{
SQLiteDatabase db = this.getWritableDatabase();
ContentValues contentValues = new ContentValues();
contentValues.put("name", name);
contentValues.put("phone", phone);
contentValues.put("email", email);
contentValues.put("street", street);
contentValues.put("place", place);
db.update("contacts", contentValues, "id = ? ", new String[] { Integer.toString(id) } );
return true;
}
public Integer deleteContact (Integer id)
{
SQLiteDatabase db = this.getWritableDatabase();
return db.delete("contacts",
"id = ? ",
new String[] { Integer.toString(id) });
}
public ArrayList<String> getAllCotacts()
{
ArrayList<String> array_list = new ArrayList<String>();
//hp = new HashMap();
SQLiteDatabase db = this.getReadableDatabase();
Cursor res = db.rawQuery( "select * from contacts", null );
res.moveToFirst();
while(res.isAfterLast() == false){
array_list.add(res.getString(res.getColumnIndex(CONTACTS_COLUMN_NAME)));
res.moveToNext();
}
return array_list;
}
the activity class
public class MainActivity extends AppCompatActivity {
Button login;
EditText student_id;
EditText password;
TextView message;
DBHelper db;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
db = new DBHelper(this);
login = (Button) findViewById(R.id.button);
student_id = (EditText) findViewById(R.id.student_id);
password = (EditText) findViewById(R.id.password);
message=(TextView)findViewById(R.id.logResult);
message.setText("");
db.insertContact("jon","9595749944","r#hotmail.com","a","usa");
login.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
String pass = password.getText().toString();
int id = Integer.parseInt(student_id.getText().toString());
int result= db.numberOfRows();
if (result == 1) {
message.setText("Invalid User");
} else {
message.setText("valid User" );
}
}
});
}
But,When the button is pressed the insertion in not occur and app close
where is the problem?? help?????????????? I want to insert data in database when the app is created how?
your call is outside of the onclick , first try:
login.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
db.insertContact("jon","9595749944","r#hotmail.com","a","usa");
}
});