What might be wrong with the following viewpager code?

I developed an app where, User can swipe the images from left to right. However, I wanted to add the sharing option So I checked this link http://ift.tt/1e4CYi1 on how to do this..However, it is not showing share option at the Actionbar. I even read the following links but I ended up with more error codes . Links I read

How do I add my app to the Android 'share photo' option?

How to use "Share image using" sharing Intent to share images in android?.

I even tried to read this blog http://ift.tt/1pO0Zkr. However, it didnt help..Being new to android and programming is driving me crazy any help will be appreciated... Following are my codes..

MainActivity.java

import android.app.Activity;
import android.content.Intent;
import android.media.MediaPlayer;
import android.os.Bundle;
import android.support.v4.view.ViewPager;
import android.view.Menu;
import android.view.MenuItem;
import android.widget.ShareActionProvider;




public class MainActivity extends Activity {

    MediaPlayer oursong;

  @Override
  public void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main);
      oursong = MediaPlayer.create(MainActivity.this, R.raw.a);
      oursong.start ();
    ViewPager viewPager = (ViewPager) findViewById(R.id.view_pager);
    ImageAdapter adapter = new ImageAdapter(this);
    viewPager.setAdapter(adapter);
  }

  private ShareActionProvider mShareActionProvider;


  @Override
  public boolean onCreateOptionsMenu(Menu menu) {
      // Inflate menu resource file.
      getMenuInflater().inflate(R.menu.activity_main, menu);

      // Locate MenuItem with ShareActionProvider
      MenuItem item = menu.findItem(R.id.menu_item_share);

      // Fetch and store ShareActionProvider
      mShareActionProvider = (ShareActionProvider) item.getActionProvider();

      // Return true to display menu
      return true;
  }

  // Call to update the share intent
  private void setShareIntent(Intent shareIntent) {
      if (mShareActionProvider != null) {
          mShareActionProvider.setShareIntent(shareIntent);
      }
  }

     @Override
     protected void onPause(){
     super.onPause();
      oursong.release();
 }

}

ImageAdapter.java

import android.content.Context;
import android.support.v4.view.PagerAdapter;
import android.support.v4.view.ViewPager;
import android.view.View;
import android.view.ViewGroup;
import android.widget.ImageView;

public class ImageAdapter extends PagerAdapter {
    Context context;
    private int[] GalImages = new int[] {
        R.drawable.one,
        R.drawable.two,
        R.drawable.three
    };
    ImageAdapter(Context context){
        this.context=context;
    }
    @Override
    public int getCount() {
      return GalImages.length;
    }

    @Override
    public boolean isViewFromObject(View view, Object object) {
      return view == ((ImageView) object);
    }

    @Override
    public Object instantiateItem(ViewGroup container, int position) {
      ImageView imageView = new ImageView(context);
      int padding = context.getResources().getDimensionPixelSize(R.dimen.padding_medium);
      imageView.setPadding(padding, padding, padding, padding);
      imageView.setScaleType(ImageView.ScaleType.CENTER_INSIDE);
      imageView.setImageResource(GalImages[position]);
      ((ViewPager) container).addView(imageView, 0);
      return imageView;
    }

    @Override
    public void destroyItem(ViewGroup container, int position, Object object) {
      ((ViewPager) container).removeView((ImageView) object);
    }
  }

Menu/activity_main.xml

   <?xml version="1.0" encoding="utf-8"?>
        <menu xmlns:android="http://ift.tt/nIICcg" >

            <item android:id="@+id/menu_item_share"
                android:showAsAction="ifRoom"
                android:title="Share"
                android:actionProviderClass="android.widget.ShareActionProvider" />

    </menu>

Manifest.xml

<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://ift.tt/nIICcg"
    package="com.manishkpr.viewpagerimagegallery"
    android:versionCode="1"
    android:versionName="1.0" >

    <uses-sdk
        android:minSdkVersion="8"
        android:targetSdkVersion="16" />

    <application
        android:allowBackup="true"
        android:icon="@drawable/ic_launcher"
        android:label="@string/app_name"
        android:theme="@style/AppTheme" >
        <activity
            android:name="com.manishkpr.viewpagerimagegallery.MainActivity"
            android:label="@string/app_name" >
            <intent-filter>
                <action android:name="android.intent.action.MAIN" />

                <category android:name="android.intent.category.LAUNCHER" />
            </intent-filter>
        </activity>
    </application>

</manifest>

activity_main.xml

<RelativeLayout xmlns:android="http://ift.tt/nIICcg"
    xmlns:tools="http://ift.tt/LrGmb4"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    tools:context=".MainActivity" >

          <android.support.v4.view.ViewPager
          android:id="@+id/view_pager"
          android:layout_width="match_parent"
          android:layout_height="match_parent" />

</RelativeLayout>