Lanjutan Dari PART 1 : PART 1
⇒Inserting new Record
Metode addContact () menerima objek Contact sebagai parameter. Kita perlu membuat parameter ContentValues menggunakan Contact object. Setelah kita memasukkan data dalam database kita perlu menutup koneksi database.
// Adding new contactpublic void addContact(Contact contact) { SQLiteDatabase db = this.getWritableDatabase(); ContentValues values = new ContentValues(); values.put(KEY_NAME, contact.getName()); // Contact Name values.put(KEY_PH_NO, contact.getPhoneNumber()); // Contact Phone Number // Inserting Row db.insert(TABLE_CONTACTS, null, values); db.close(); // Closing database connection} |
⇒Reading Row(s)
Metode berikut getContact () akan membaca satu baris kontak. Ini menerima id sebagai parameter dan akan mengembalikan baris yang cocok dari database.
// Getting single contactpublic Contact 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); if (cursor != null) cursor.moveToFirst(); Contact contact = new Contact(Integer.parseInt(cursor.getString(0)), cursor.getString(1), cursor.getString(2)); // return contact return contact;} |
getAllContacts () akan mengembalikan semua kontak dari database dalam format daftar array tipe kelas Kontak. Anda perlu menulis sebuah loop untuk melewati setiap kontak.
// Getting All Contacts public List<Contact> getAllContacts() { List<Contact> contactList = new ArrayList<Contact>(); // Select All Query String selectQuery = "SELECT * FROM " + TABLE_CONTACTS; SQLiteDatabase db = this.getWritableDatabase(); Cursor cursor = db.rawQuery(selectQuery, null); // looping through all rows and adding to list if (cursor.moveToFirst()) { do { Contact contact = new Contact(); 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;} |
getContactsCount() akan mengembalikan jumlah total kontak di database SQLite.
// Getting contacts Count public int getContactsCount() { String countQuery = "SELECT * FROM " + TABLE_CONTACTS; SQLiteDatabase db = this.getReadableDatabase(); Cursor cursor = db.rawQuery(countQuery, null); cursor.close(); // return count return cursor.getCount(); } |
⇒Updating Record
updateContact() akan mengupdate satu kontak dalam database. Metode ini menerima objek kelas Kontak sebagai parameter.
// Updating single contactpublic int updateContact(Contact contact) { SQLiteDatabase db = this.getWritableDatabase(); ContentValues values = new ContentValues(); values.put(KEY_NAME, contact.getName()); values.put(KEY_PH_NO, contact.getPhoneNumber()); // updating row return db.update(TABLE_CONTACTS, values, KEY_ID + " = ?", new String[] { String.valueOf(contact.getID()) });} |
⇒Deleting Record
deleteContact() akan menghapus satu kontak dari database.
Complete DatabaseHandler.java Code:
package com.androidhive.androidsqlite;import java.util.ArrayList;import java.util.List;import android.content.ContentValues;import android.content.Context;import android.database.Cursor;import android.database.sqlite.SQLiteDatabase;import android.database.sqlite.SQLiteOpenHelper;public class DatabaseHandler extends SQLiteOpenHelper { // All Static variables // Database Version 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"; private static final String KEY_NAME = "name"; private static final String KEY_PH_NO = "phone_number"; public DatabaseHandler(Context context) { super(context, DATABASE_NAME, null, DATABASE_VERSION); } // Creating Tables @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); } // Upgrading database @Override public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) { // Drop older table if existed db.execSQL("DROP TABLE IF EXISTS " + TABLE_CONTACTS); // Create tables again onCreate(db); } /** * All CRUD(Create, Read, Update, Delete) Operations */ // Adding new contact void addContact(Contact contact) { SQLiteDatabase db = this.getWritableDatabase(); ContentValues values = new ContentValues(); values.put(KEY_NAME, contact.getName()); // Contact Name values.put(KEY_PH_NO, contact.getPhoneNumber()); // Contact Phone // Inserting Row db.insert(TABLE_CONTACTS, null, values); db.close(); // Closing database connection } // Getting single contact Contact 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); if (cursor != null) cursor.moveToFirst(); Contact contact = new Contact(Integer.parseInt(cursor.getString(0)), cursor.getString(1), cursor.getString(2)); // return contact return contact; } // Getting All Contacts public List<Contact> getAllContacts() { List<Contact> contactList = new ArrayList<Contact>(); // Select All Query String selectQuery = "SELECT * FROM " + TABLE_CONTACTS; SQLiteDatabase db = this.getWritableDatabase(); Cursor cursor = db.rawQuery(selectQuery, null); // looping through all rows and adding to list if (cursor.moveToFirst()) { do { Contact contact = new Contact(); 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; } // Updating single contact public int updateContact(Contact contact) { SQLiteDatabase db = this.getWritableDatabase(); ContentValues values = new ContentValues(); values.put(KEY_NAME, contact.getName()); values.put(KEY_PH_NO, contact.getPhoneNumber()); // updating row return db.update(TABLE_CONTACTS, values, KEY_ID + " = ?", new String[] { String.valueOf(contact.getID()) }); } // Deleting single contact public void deleteContact(Contact contact) { SQLiteDatabase db = this.getWritableDatabase(); db.delete(TABLE_CONTACTS, KEY_ID + " = ?", new String[] { String.valueOf(contact.getID()) }); db.close(); } // Getting contacts Count public int getContactsCount() { String countQuery = "SELECT * FROM " + TABLE_CONTACTS; SQLiteDatabase db = this.getReadableDatabase(); Cursor cursor = db.rawQuery(countQuery, null); cursor.close(); // return count return cursor.getCount(); }} |
Usage:
package com.androidhive.androidsqlite;import java.util.List;import android.app.Activity;import android.os.Bundle;import android.util.Log;import android.widget.TextView;public class AndroidSQLiteTutorialActivity extends Activity { @Override public void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.main); DatabaseHandler db = new DatabaseHandler(this); /** * CRUD Operations * */ // Inserting Contacts Log.d("Insert: ", "Inserting .."); db.addContact(new Contact("Ravi", "9100000000")); db.addContact(new Contact("Srinivas", "9199999999")); db.addContact(new Contact("Tommy", "9522222222")); db.addContact(new Contact("Karthik", "9533333333")); // Reading all contacts Log.d("Reading: ", "Reading all contacts.."); List<Contact> contacts = db.getAllContacts(); for (Contact cn : contacts) { String log = "Id: "+cn.getID()+" ,Name: " + cn.getName() + " ,Phone: " + cn.getPhoneNumber(); // Writing Contacts to log Log.d("Name: ", log); } }} |
Android Log Cat Report:
I am writing output to Log report. You can see your log report by going to Windows ⇒ Show View ⇒ Other.. ⇒ Android ⇒ Log Cat.