Android SQLite Veri Tabanı Basit CRUD İşlemleri

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:id="@+id/activity_main"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:paddingBottom="@dimen/activity_vertical_margin"
android:paddingLeft="@dimen/activity_horizontal_margin"
android:paddingRight="@dimen/activity_horizontal_margin"
android:paddingTop="@dimen/activity_vertical_margin"
android:orientation="vertical"
tools:context="com.example.sqlite.MainActivity">

<EditText
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:id="@+id/textViewName" />

<EditText
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:id="@+id/textViewEmail" />

<Button
android:text="ADD"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:id="@+id/button" />
</LinearLayout>

public class DBAdapter {
static final String KEY_ROWID = "_id";
static final String KEY_NAME = "name";
static final String KEY_EMAIL = "email";
static final String TAG = "DBAdapter";

static final String DATABASE_NAME = "MyDB";
static final String DATABASE_TABLE = "contacts";
static final int DATABASE_VERSION = 2;

static final String DATABASE_CREATE =
"create table contacts (_id integer primary key autoincrement, "
+ "name text not null, email text not null);";

final Context context;

DatabaseHelper DBHelper;
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)
{
try {
db.execSQL(DATABASE_CREATE);
} catch (SQLException e) {
e.printStackTrace();
}
}

@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");
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 contact into the database---
public long insertContact(String name, String email)
{
ContentValues initialValues = new ContentValues();
initialValues.put(KEY_NAME, name);
initialValues.put(KEY_EMAIL, email);
return db.insert(DATABASE_TABLE, null, initialValues);
}

//---deletes a particular contact---
public boolean deleteContact(long rowId)
{
return db.delete(DATABASE_TABLE, KEY_ROWID + "=" + rowId, null) > 0;
}

//---retrieves all the contacts---
public Cursor getAllContacts()
{
return db.query(DATABASE_TABLE, new String[] {KEY_ROWID, KEY_NAME,
KEY_EMAIL}, null, null, null, null, null);
}

//---retrieves a particular contact---
public Cursor getContact(long rowId) throws SQLException
{
Cursor mCursor =
db.query(true, DATABASE_TABLE, new String[] {KEY_ROWID,
KEY_NAME, KEY_EMAIL}, KEY_ROWID + "=" + rowId, null,
null, null, null, null);
if (mCursor != null) {
mCursor.moveToFirst();
}
return mCursor;
}

//---updates a contact---
public boolean updateContact(long rowId, String name, String email)
{
ContentValues args = new ContentValues();
args.put(KEY_NAME, name);
args.put(KEY_EMAIL, email);
return db.update(DATABASE_TABLE, args, KEY_ROWID + "=" + rowId, null) > 0;
}
}

package com.example.sqlite;

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.TextView;
import android.widget.Toast;

public class MainActivity extends AppCompatActivity {

final DBAdapter db = new DBAdapter(this);

@Override
public void onCreate(final Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);

Button button = (Button) findViewById(R.id.button);
final TextView textViewName = (TextView) findViewById(R.id.textViewName);
final TextView textViewEmail = (TextView) findViewById(R.id.textViewEmail);

button.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View view) {

long id = AddContact(textViewName.getText().toString(),textViewEmail.getText().toString());
Toast.makeText(MainActivity.this, "id: " + id + "\n", Toast.LENGTH_SHORT).show();
}
});

//---add a contact---
/* db.open();
long id = db.insertContact("xor software Group", "berkayakcay.d@gmail.com");
id = db.insertContact("berkay akacay", "berkayakcay.d@gmail.com");
db.close();*/

//--get all contacts---
// db.open();
// Cursor c = db.getAllContacts();
// if (c.moveToFirst())
// {
// do {
// DisplayContact(c);
// } while (c.moveToNext());
// }
// db.close();
/*
//---get a contact---
db.open();
Cursor c = db.getContact(2);
if (c.moveToFirst())
DisplayContact(c);
else
Toast.makeText(this, "No contact found", Toast.LENGTH_LONG).show();
db.close();
//---update contact---
db.open();
if (db.updateContact(1, "datis software Group", "datis@yahoo.com"))
Toast.makeText(this, "Update successful.", Toast.LENGTH_LONG).show();
else
Toast.makeText(this, "Update failed.", Toast.LENGTH_LONG).show();
db.close();
db.open();
if (db.deleteContact(1))
Toast.makeText(this, "Delete successful.", Toast.LENGTH_LONG).show();
else
Toast.makeText(this, "Delete failed.", Toast.LENGTH_LONG).show();
db.close();*/

}
public long AddContact(String name, String email)
{
db.open();
long id = db.insertContact(name, email);
db.close();
return id;
}
public void DisplayContact(Cursor c)
{
Toast.makeText(this,
"id: " + c.getString(0) + "\n" +
"Name: " + c.getString(1) + "\n" +
"Email: " + c.getString(2),
Toast.LENGTH_LONG).show();
}
}