protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main);

    SQLiteDatabase sqLiteDatabase = getBaseContext().openOrCreateDatabase("ContactsDB.db", MODE_PRIVATE, null);

    lv = (ListView) findViewById(R.id.contactListView2);
    buttonAdd = (Button) findViewById(R.id.buttonAdd);

    String tempSQL = "CREATE TABLE IF NOT EXISTS contactsList(_id INTEGER PRIMARY KEY AUTOINCREMENT NOT NULL,firstName TEXT,lastName TEXT,phone TEXT,email TEXT,address TEXT,note TEXT);";
    sqLiteDatabase.execSQL(tempSQL);
    Log.d(TAG, "onCreate: Table created");

    db = openOrCreateDatabase("ContactsDB.db", MODE_PRIVATE, null);

    //show name in listView

    Cursor cursor2 = db.rawQuery("SELECT firstName FROM contactsList;", null);
    ArrayList ar = new ArrayList();//new

    while (cursor2.moveToNext()) {
        ar.add(cursor2.getString(0));
    }

    ArrayAdapter arrayAdapter = new ArrayAdapter(this, android.R.layout.simple_list_item_1, ar);
    lv.setAdapter(arrayAdapter);
    Log.d(TAG, "onCreate: showlist : list showing in listview now.");

    //setting for showing the edit layout

    lv.setOnItemClickListener(new AdapterView.OnItemClickListener() {
        @Override
        public void onItemClick(AdapterView<?> adapterView, View view, int i, long l) {
            Cursor cr = db.rawQuery("SELECT * FROM contactsList WHERE firstName='"+lv.getItemAtPosition(i).toString()+"'",null);
            StringBuffer sb = new StringBuffer();
            while(cr.moveToNext()){
                sb.append(cr.getString(0)+"n");
            }
            Intent showAddLayout = new Intent(MainActivity.this, editContact.class);
            showAddLayout.putExtra("name",sb.toString());
            startActivity(showAddLayout);
        }
    });



    //button click listener to show other LayOut or page

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

            Intent showAddLayout = new Intent(MainActivity.this, addNewContact.class);
            startActivity(showAddLayout);


        }
    });

}//end of onCreate

<item
    android:id="@+id/action_search"
    android:icon="@android:drawable/ic_search_category_default"
    android:title="@string/menu_search"
    app:actionViewClass="android.widget.SearchView"
    app:showAsAction="ifRoom|collapseActionView" />

<?xml version="1.0" encoding="utf-8"?>
<menu xmlns:app="http://schemas.android.com/apk/res-auto"
    xmlns:android="http://schemas.android.com/apk/res/android">
    <item
        android:id="@+id/menu_search"
        android:icon="@android:drawable/ic_search_category_default"
        android:title="@string/menu_search"
        app:actionViewClass="android.widget.SearchView"
        app:showAsAction="ifRoom|collapseActionView" />
</menu>

private SearchView mSearchView;

Intent intent = getIntent();
if (Intent.ACTION_SEARCH.equals(intent.getAction())) {
    mSearchString = intent.getStringExtra(SearchManager.QUERY);
    //System.out.println(query);
}

getMenuInflater().inflate(R.menu.menu_main, menu);
MenuItem searchMenuItem = menu.findItem(R.id.action_search);
mSearchView = (SearchView) MenuItemCompat.getActionView(searchMenuItem);
setupSearchResult(searchMenuItem);

private void setupSearchResult(MenuItem searchItem) {
    SearchManager searchManager =
            (SearchManager) getSystemService(Context.SEARCH_SERVICE);
    mSearchView.setSearchableInfo(
            searchManager.getSearchableInfo(getComponentName()));
}