Control is not Entering in ContextMenu in android?

Question

Here control is not entering in ContextMenu and not print toast. i don't know why? and what i am missing here, simply i want to show context menu on long press, i tries it many days but still going to fail to solve it. i tried many method from yesterday but still contextmenu not working please help me what i am missing here.

public class MainActivity extends AppCompatActivity {

ListView listView;
Button sync;
ProgressDialog progressDialog;
String name, phone;

ArrayList<Contact_list> listitem;


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



    listitem = new ArrayList<Contact_list>();

    listView = (ListView) findViewById(R.id.listViewID);
    registerForContextMenu(listView);

    sync= (Button) findViewById(R.id.syncID);
    sync.setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View v) {

            // GET CONTACTS DATA


            GetContactsIntoArrayList();


            listView.setAdapter(new Custom_adapter(MainActivity.this, listitem));

            Toast.makeText(MainActivity.this, "import", Toast.LENGTH_SHORT).show();
        }
    });
}

public void GetContactsIntoArrayList(){
    Cursor cursor;
    cursor = getContentResolver().query(ContactsContract.CommonDataKinds.Phone.CONTENT_URI, null,null, null, null);

    while (cursor.moveToNext()) {

        name = cursor.getString(cursor.getColumnIndex(ContactsContract.CommonDataKinds.Phone.DISPLAY_NAME));

        phone = cursor.getString(cursor.getColumnIndex(ContactsContract.CommonDataKinds.Phone.NUMBER));


        listitem.add(new Contact_list(name,phone));



        listView.setAdapter(new Custom_adapter(MainActivity.this, listitem));

    }

    cursor.close();

    listView.setOnItemLongClickListener(new AdapterView.OnItemLongClickListener() {

        public boolean onItemLongClick(AdapterView<?> arg0, View v,
                                       int index, long arg3) {
            // TODO Auto-generated method stub

            Log.v("long clicked","pos: " + index);


            //Log.d("tag", "message");
            String str=listView.getItemAtPosition(index).toString();

            Log.d("long click sucessfull: " ,str);
            return true;
        }
    });

}
 //Here control is not entering in Contextmenu why?
 @Override
 public void onCreateContextMenu(ContextMenu menu, View v,ContextMenu.ContextMenuInfo menuInfo)
   {

       super.onCreateContextMenu(menu, v, menuInfo);

    Toast.makeText(MainActivity.this, "Entering Context Menu",  Toast.LENGTH_SHORT).show();

       getMenuInflater().inflate(R.menu.main, menu);

       menu.setHeaderTitle("Select The Action");
       menu.add(0, v.getId(), 0, "Call");
       menu.add(0, v.getId(), 0, "Send SMS");

}


@Override
public boolean onContextItemSelected(MenuItem item)
{


    AdapterView.AdapterContextMenuInfo info = (AdapterView.AdapterContextMenuInfo)item.getMenuInfo();


        return true;


    }


}