An example pf how to create twitter-like custom menu overflow listview using ListPopupWindow

MainActivity.java

package com.rowland.magent;

import android.support.v4.app.FragmentManager;
import android.support.v4.app.FragmentTransaction;
import android.support.v7.app.ActionBarActivity;
import android.os.Bundle;
import android.support.v7.widget.ListPopupWindow;
import android.support.v7.widget.Toolbar;
import android.util.Log;
import android.view.Menu;
import android.view.MenuItem;
import android.view.View;
import android.widget.AdapterView;
import android.widget.Toast;

import com.readystatesoftware.systembartint.SystemBarTintManager;

import com.rowland.adapters.ListPopupWindowAdapter;
import com.rowland.fragments.DetailsFragment;
import com.rowland.fragments.MainFragment;
import com.rowland.objects.Person;

import java.util.ArrayList;


public class MainActivity extends ActionBarActivity {

    private final String LOG_TAG = MainActivity.class.getSimpleName();
    private boolean mTwoPane;
    private Toolbar mToolbar;
    private SystemBarTintManager mTintManager;

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

        // Initialize the mToolbar and set it as an ActionBar
        this.mToolbar = (Toolbar) findViewById(R.id.toolbar);
        setSupportActionBar(mToolbar);
        getSupportActionBar().setDisplayShowTitleEnabled(false);
        getSupportActionBar().setIcon(R.drawable.ic_logo_48px);
        this.mToolbar.setLogo(R.drawable.ic_logo_48px);

        // Create our manager instance after the content view is set & enable status bar tint
        this.mTintManager = new SystemBarTintManager(this);
        this.mTintManager.setStatusBarTintEnabled(true);
        this.mTintManager.setTintColor(R.attr.colorPrimaryDark);

        if (findViewById(R.id.detail_container) != null)
        {
            // The detail container view will be present only in the large-screen layouts
            // (res/layout-sw600dp). If this view is present, then the activity should be
            // in two-pane mode.
            mTwoPane = true;
            // If we're being restored from a previous state, don't need to do anything
            // and should return or else we could end up with overlapping fragments.
            if (savedInstanceState != null)
            {
                return;
            }
            else
            {
                // In two-pane mode, show the detail view in this activity by
                // adding or replacing the detail fragment using a fragment transaction.
                showDetailFragment(null);
            }
        }
        else
        {
            mTwoPane = false;
        }

        showMainFragment(null);

    }

    private void showDetailFragment(Bundle args)
    {
        FragmentManager fm = getSupportFragmentManager();

        FragmentTransaction ft = fm.beginTransaction();

        DetailsFragment fragment = DetailsFragment.newInstance(args);

        ft.replace(R.id.detail_container, fragment);
        ft.commit();
    }

    private void showMainFragment(Bundle args)
    {
        FragmentManager fm = getSupportFragmentManager();

        FragmentTransaction ft = fm.beginTransaction();

        MainFragment fragment  = MainFragment.newInstance(args);

        ft.add(R.id.fragment_container, fragment);
        ft.commit();
    }

  @Override
    public boolean onCreateOptionsMenu(Menu menu)
    {
        // Inflate the menu; this adds items to the action bar if it is present.
        getMenuInflater().inflate(R.menu.menu_main, menu);

        return super.onCreateOptionsMenu(menu);

    }

    @Override
    public boolean onOptionsItemSelected(MenuItem item)
    {
        switch (item.getItemId())
        {
            case R.id.action_search:

                Log.w(LOG_TAG, "You called me Search");
                return true;
            case R.id.action_overflow:

                // Works as long as list item is always visible and does not go into the menu overflow
                final View menuItemView = findViewById(R.id.action_overflow);
                onListPopUp(menuItemView);
                Log.w(LOG_TAG, "You called me OverFlow");
                return true;
            default:
            {
                return super.onOptionsItemSelected(item);
            }
        }
    }

    public void onListPopUp(View anchor)
    {
        // This a sample dat to fill our ListView
        ArrayList<Person> personItem = new ArrayList<Person>();
        personItem.add(new Person(R.drawable.remove_placeholder_userpic, "Mamluki", "@DigitalSurgeonR"));
        personItem.add(new Person(0, "Lists", "@Lists"));
        personItem.add(new Person(0, "Drafts", "@Drafts"));
        personItem.add(new Person(0, "Accounts", "@Accounts"));
        // Initialise our adapter
        ListPopupWindowAdapter mListPopUpAdapter = new ListPopupWindowAdapter(this, personItem);

        //Initialise our ListPopupWindow instance
        final ListPopupWindow pop = new ListPopupWindow(this);
        // Configure ListPopupWindow properties
        pop.setAdapter(mListPopUpAdapter);
        // Set the view below/above which ListPopupWindow dropdowns
        pop.setAnchorView(anchor);
        // Setting this enables window to be dismissed by click outside ListPopupWindow
        pop.setModal(true);
        // Sets the width of the ListPopupWindow
        pop.setContentWidth(150);
        // Sets the Height of the ListPopupWindow
        pop.setHeight(ListPopupWindow.WRAP_CONTENT);
        // Set up a click listener for the ListView items
        pop.setOnItemClickListener(new AdapterView.OnItemClickListener() {
            @Override
            public void onItemClick(AdapterView<?> adapterView, View view, int position, long l) {
                // Dismiss the LisPopupWindow when a list item is clicked
                pop.dismiss();
                Toast.makeText(MainActivity.this, "Clicked ListPopUp item " + ((Person) adapterView.getItemAtPosition(position)).getName(), Toast.LENGTH_LONG).show();
            }
        });
        pop.show();
    }
}

I am having a issue. The menu runs to the right of the screen https://www.dropbox.com/s/jensnnjox7urlhi/g8Glr.jpg?dl=0