If you want to create Share Action Provider function check my below example. Here I have created frist main.xml. After creating main.xml I have added attribute to the menu item. In MainActivity created onCreateOptionsMenu method I sets the share action provider using setShareIntent. See the below example code it will clearly described you how to create ShareActionProvider function.

Step(1)-Manifest file-

<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
    package="com.tiwari.rajshekhar.shareprovider"
    android:versionCode="1"
    android:versionName="1.0">
    <uses-sdk
        android:minSdkVersion="14"
        android:targetSdkVersion="19"/>

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

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

Step(2)-xml.layout-

<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:paddingBottom="@dimen/activity_vertical_margin"
    android:paddingLeft="@dimen/activity_horizontal_margin"
    android:paddingRight="@dimen/activity_horizontal_margin"
    android:paddingTop="@dimen/activity_vertical_margin"
    tools:context=".MainActivity" >

    <TextView
        android:id="@+id/textView1"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_alignParentLeft="true"
        android:layout_alignParentRight="true"
        android:layout_alignParentTop="true"
        android:layout_marginTop="178dp"
        android:text="Welcome to share provider screen"
        android:textAppearance="?android:attr/textAppearanceLarge" />

</RelativeLayout>

Step(3)-MainActivity-

public class MainActivity extends Activity {
     private ShareActionProvider mShareActionProvider;
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
    }
     @Override
     public boolean onCreateOptionsMenu(Menu menu) {
          getMenuInflater().inflate(R.menu.main, menu);
          MenuItem item = menu.findItem(R.id.menu_item_share);
          // Fetch and store ShareActionProvider
          mShareActionProvider = (ShareActionProvider) item.getActionProvider();
          setShareIntent(createShareIntent());
          return true;
     }
     private void setShareIntent(Intent shareIntent) {
          if (mShareActionProvider != null) {
               mShareActionProvider.setShareIntent(shareIntent);
          }
     }
     private Intent createShareIntent() {
          Intent shareIntent = new Intent(Intent.ACTION_SEND);
          shareIntent.setType("text/plain");
          shareIntent.putExtra(Intent.EXTRA_TEXT,
                    "http://findnerd.com");
          return shareIntent;
     }
}