Example to create Menu

Modify /res/menu/main.xml to define menu items.

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

    <item
        android:id="@+id/action_settings"
        android:orderInCategory="100"
        android:showAsAction="never"
        android:title="@string/action_settings"/>
    
    <item
        android:id="@+id/action_up"
        android:orderInCategory="100"
        android:showAsAction="ifRoom|withText"
        android:icon="@android:drawable/arrow_up_float"
        android:title="Up"/>
    <item
        android:id="@+id/action_down"
        android:orderInCategory="100"
        android:showAsAction="ifRoom|withText"
        android:icon="@android:drawable/arrow_down_float"
        android:title="Down"/>
    <item
        android:id="@+id/action_other"
        android:orderInCategory="100"
        android:showAsAction="ifRoom"
        android:icon="@drawable/ic_launcher"
        android:title="Other"/>

</menu>

To load menu, override onCreateOptionsMenu() method to inflate R.menu.main. It's loaded in default generated code.

To handle menu item selected, override onOptionsItemSelected() method.

MainActivity.java

package com.example.androidmenu;

import android.os.Bundle;
import android.app.Activity;
import android.view.Menu;
import android.view.MenuItem;
import android.widget.Toast;

public class MainActivity extends Activity {

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

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

 @Override
 public boolean onOptionsItemSelected(MenuItem item) {
  
  switch(item.getItemId()){
  case R.id.action_settings:
   Toast.makeText(getApplicationContext(), 
     "Setting...", 
     Toast.LENGTH_SHORT).show();
   break;
  case R.id.action_up:
   Toast.makeText(getApplicationContext(), 
     "Up...", 
     Toast.LENGTH_SHORT).show();
   break;
  case R.id.action_down:
   Toast.makeText(getApplicationContext(), 
     "Down...", 
     Toast.LENGTH_SHORT).show();
   break;
  case R.id.action_other:
   Toast.makeText(getApplicationContext(), 
     "Other...", 
     Toast.LENGTH_SHORT).show();
   break;
  default:
   Toast.makeText(getApplicationContext(), 
     "Unknown...", 
     Toast.LENGTH_SHORT).show();
   break;
  }
  
  //Return false to allow normal menu processing to proceed, 
  //true to consume it here.
  return false;
 }
 
}

Next:
- Show and hide menu item programatically