SQLite Example - Register New User and View All Registered User

Dear All

" Happy Holi......"

What is SQLite :

SQLite is an in-process Library used to work with Database for Mobile OS(Mostly).
@ It's Server-Less
@ Already Configured
@ Follow ACID Property
@ Structured Database
@ No Dependency

How to work with Database in Android  :
Step 1 : Define Schema
             " Means Define Database name , table name , column name ..........."
Step 2: Create Database
             a.  Create a Class by extending SQLiteOpenHelper
             b.  Override  onCreate(SQLiteDatabase ob) method -
                   Like ob.execSQL(" String query")
             c. Override onUpgrade(SQLiteDatabase db, int oldVersion, int                                                 newVersion)
          if any alter in Table 
Step 3: Execute Query 
       a. Create object of SQLiteDatabase   either by                                  using getWritableDatabase() or 
          getReadableDatabase()  with the help of Helper class                         object 
       b. Use ContentValues  class object to put like key-value pair                   data
       c. Execute query like insert() , update().... by                               using SQLiteDatabase object

Just See the example :
A. Output will be like
     a. First Screen - Launched Activity

    XML Code for this

<?xml version="1.0" encoding="utf-8"?>

<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"

    xmlns:app="http://schemas.android.com/apk/res-auto"

    xmlns:tools="http://schemas.android.com/tools"

    android:layout_width="match_parent"

    android:layout_height="match_parent"

    tools:context="com.example.ravigodara.sql2017ex1.MainActivity"

    tools:layout_editor_absoluteY="81dp"

    tools:layout_editor_absoluteX="0dp">

    <Button        android:id="@+id/button"

        android:layout_width="368dp"

        android:layout_height="48dp"

        android:layout_alignEnd="@+id/button2"

        android:layout_alignParentTop="true"

        android:layout_marginTop="62dp"

        android:text="Register"

        tools:layout_editor_absoluteX="8dp"

        tools:layout_editor_absoluteY="45dp"

        android:onClick="reg"/>

    <Button        android:id="@+id/button2"

        android:layout_width="368dp"        android:layout_height="48dp"

        android:text="Registered User"

        tools:layout_editor_absoluteX="8dp"   tools:layout_editor_absoluteY="151dp"

        android:layout_alignParentBottom="true"

        android:layout_centerHorizontal="true"

        android:layout_marginBottom="109dp"

        android:onClick="showData"/>

</RelativeLayout> 
 b.  Second Screen - When you click on Register

XML Code for this layout

<?xml version="1.0" encoding="utf-8"?>

<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"

    android:layout_width="match_parent" android:layout_height="match_parent">

    <TextView        android:layout_width="wrap_content"

        android:layout_height="wrap_content"

        android:textAppearance="?android:attr/textAppearanceLarge"

        android:text="UserName"        android:id="@+id/textView"

        android:layout_alignParentTop="true"

        android:layout_alignParentStart="true" />

    <TextView

        android:layout_width="wrap_content"

        android:layout_height="wrap_content"

        android:textAppearance="?android:attr/textAppearanceLarge"

        android:text="Password"        android:id="@+id/textView2"

        android:layout_below="@+id/textView"

        android:layout_alignEnd="@+id/textView"

        android:layout_marginTop="44dp" />

    <EditText        android:layout_width="wrap_content"

        android:layout_height="wrap_content"

        android:id="@+id/userN"     android:layout_alignParentTop="true"

        android:layout_alignParentEnd="true"

        android:layout_toEndOf="@+id/textView" />

    <EditText

        android:layout_width="wrap_content"

        android:layout_height="wrap_content"      android:id="@+id/userP"

        android:inputType="textPassword"

        android:layout_alignBottom="@+id/textView2"

        android:layout_alignParentEnd="true"

        android:layout_toEndOf="@+id/textView2" />

    <Button        android:layout_width="wrap_content"

        android:layout_height="wrap_content"

        android:text="Register"

        android:id="@+id/button"

        android:layout_centerVertical="true"

        android:layout_centerHorizontal="true" />

</RelativeLayout> 
  c. Third Screen - All registered User

XML Code for this layout

<?xml version="1.0" encoding="utf-8"?>

<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"

    xmlns:app="http://schemas.android.com/apk/res-auto"

    xmlns:tools="http://schemas.android.com/tools"

    android:layout_width="match_parent"

    android:layout_height="match_parent"

    tools:context="com.example.ravigodara.sql2017ex1.ViewData">

    <ListView

        android:layout_width="wrap_content"   android:layout_height="wrap_content"

        android:id="@+id/listView"

        android:layout_alignParentStart="true"

        android:layout_alignParentTop="true" />
</RelativeLayout>

Single Row Layout File 

<?xml version="1.0" encoding="utf-8"?>

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"

    android:orientation="horizontal" android:layout_width="match_parent"

    android:layout_height="match_parent"

    android:weightSum="1">

    <TextView

        android:layout_width="wrap_content"    android:layout_height="39dp"

        android:text="New Text"        android:gravity="center"

        android:id="@+id/text_id"        android:layout_weight="0.06" />

    <TextView        android:layout_width="wrap_content"

        android:layout_height="41dp"

        android:text="New Text"        android:gravity="center"

        android:id="@+id/text_name"        android:layout_weight="0.90" />
    <TextView        android:layout_width="159dp"

        android:layout_height="37dp"

        android:text="New Text"        android:gravity="center"

        android:id="@+id/text_pass" />
</LinearLayout>

B. Java Code

a. MainActivity.java   code is

package com.example.ravigodara.sql2017ex1;

import android.content.Intent;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.view.View;

public class MainActivity extends AppCompatActivity {

    @Override    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
    }
    public void reg(View view)
    {
        startActivity(new Intent(this, Register.class));
    }
    public void showData(View view)
    {
        Intent iob = new Intent(this,ViewData.class);
        startActivity(iob);
    }

}

b. Register.java code is as

package com.example.ravigodara.sql2017ex1;

import android.content.Context;
import android.os.Bundle;
import android.support.v7.app.AppCompatActivity;
import android.view.View;
import android.widget.Button;
import android.widget.EditText;
import android.widget.Toast;

/** * Created by Ravi Godara on 3/10/2017. */
public class Register extends AppCompatActivity {

    EditText etus, etpass;
    String struser, strpass;
    Button reg;
    Context cob = this;

    @Override    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.regist);
        etus = (EditText) findViewById(R.id.userN);
        etpass = (EditText) findViewById(R.id.userP);

        reg = (Button) findViewById(R.id.button);
        reg.setOnClickListener(new View.OnClickListener() {
            @Override            public void onClick(View v) {
                struser = etus.getText().toString();
                strpass = etpass.getText().toString();


                DbHelper myob = new DbHelper(cob);
                    myob.putInfo(myob, struser, strpass);
                    Toast.makeText(getBaseContext(), 

                          "Registered Successfully", Toast.LENGTH_LONG).show();
                    finish();

            }
        });
    }

}

c. To See all Registered User is as

package com.example.ravigodara.sql2017ex1;

import android.content.Context;
import android.database.Cursor;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.widget.ListView;
import android.widget.SimpleCursorAdapter;

public class ViewData extends AppCompatActivity {
    Context context = this;

    @Override    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_view_data);
        showListView();
    }

    private void showListView() {
        DbHelper myHelper = new DbHelper(context);
        Cursor cursorOb = myHelper.getAllRows(myHelper);
        String[] fromDB = new String[]{DbHelper.KEY_ID, DbHelper.USER_NAME, 

                           DbHelper.USER_PAS};
        int[] toShow = new int[]{R.id.text_id, R.id.text_name, R.id.text_pass};
        SimpleCursorAdapter simpleCursorAdapter = new SimpleCursorAdapter

                 (getBaseContext(), R.layout.onerow, cursorOb, fromDB, toShow, 0);
        ListView listView = (ListView) findViewById(R.id.listView);
        listView.setAdapter(simpleCursorAdapter);
    }

}

d. DataBase Helper class is as

package com.example.ravigodara.sql2017ex1;

import android.content.ContentValues;
import android.content.Context;
import android.database.Cursor;
import android.database.sqlite.SQLiteDatabase;
import android.database.sqlite.SQLiteOpenHelper;
import android.util.Log;

public class DbHelper extends SQLiteOpenHelper {
    public static final String KEY_ID="_id";
    public static final String USER_NAME="user_name";
    public static final String USER_PAS="user_pass";
    private static final String DB_NAME="mydb.db";
    private static final String TAB_NAME="myinfo";
    private static final int DB_VER=1;
    private static final  String CREATE_QUERY = "create table " + TAB_NAME + " ( "

                    + KEY_ID + " integer primary key autoincrement, " +
            USER_NAME + " text not null, " + USER_PAS + " text not null );";

    public DbHelper(Context context)
    {
        super(context,DB_NAME,null,1);
    }
    @Override    public void onCreate(SQLiteDatabase sdb) {

        sdb.execSQL(CREATE_QUERY);
        Log.d("rrrr", "oncreate");
    }

    @Override public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion)

     {
        db.execSQL("DROP TABLE IF EXISTS " + TAB_NAME);
        Log.d("hello", "onupgrade");
        onCreate(db);

    }
    public  void putInfo(DbHelper mob,String name,String pass)
    {
        SQLiteDatabase SQ= mob.getWritableDatabase();
        ContentValues CV=new ContentValues();
        CV.put(USER_NAME, name);
        CV.put(USER_PAS, pass);
        SQ.insert(TAB_NAME, null, CV);
    }

    public Cursor getAllRows(DbHelper mob)
    {
        SQLiteDatabase SQ = mob.getReadableDatabase();
        Cursor cob = SQ.query(TAB_NAME,null,null,null,null,null,null);
        if(cob!=null)
        {
            cob.moveToFirst();
        }
        return cob;
    }

}